Re: [Elecraft] Yamaha Headphones

[John Marvin]

Proximity effect has nothing to do with the technology of the 
transducer, i.e. dynamic, condenser, electret, ribbon, etc.


Proximity effect is due to the type of transducer, i.e. whether it is a 
pressure transducer or a pressure gradient transducer or a mix of the 
two. That determines the pickup pattern, and that also determines the 
amount of proximity effect the mike has.  A pure pressure transducer has 
an omni-directional pickup pattern and absolutely no proximity effect.  
A pure pressure gradient transducer has a figure 8 pickup pattern (i.e. 
bidirectional cardiod) and the highest level of proximity effect.  One 
of the most common pickup patterns is the cardioid pattern, which is a 
directional pattern and has a decent amount of proximity effect.


Your experience with dynamic vs. condenser mics was probably more to do 
with the pickup pattern. There are a variety of "cardioid" patterns, one 
of them being hyper cardioid, which is more prevalent in condenser 
mikes.  It is more directional than a cardioid and has further "reach", 
which would allow a vocalist to be further away from the mike and still 
be picked up well (but would fall of quicker if they moved off to the 
side).  That further distance could significantly reduce or eliminate 
proximity effect.


Another possibility is a sub cardioid pattern which is less directional 
than a standard cardioid pattern, which would also have less proximity 
effect at the same distance from the mike.


John
AC0ZG

On 11/21/2022 2:56 PM, Joe Subich, W4TV wrote:

An electret mic is much easier/cheaper to manufacture than an
equivalent dynamic capsule.  With the built-in FET follower,
the electret output is some 20-25dB higher than the dynamic
making RFI and hum reduction much easier to manage in consumer
electronics.  In addition, the electret does not suffer as
badly from the proximity effect that is common with all dynamic
mics (a benefit of using condenser mics for studio vocals -
particularly with vocalists that don't know good mic technique!).


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] 99.9 % alcohol

[John Marvin]

Anything above 95% or so requires processes beyond just distillation, 
i.e. you are getting into the lab grade region. Prices usually go up 
significantly for that.


Of course, in many states you can buy 190 proof Everclear (95% grain 
alcohol) at a liquor store.  Might be easier to find than lab grade 
alcohol.  One advantage is that since it is not denatured, the fumes are 
significantly less toxic.


Since alcohol is hydrophilic, it helps to evaporate the water that makes 
up the rest of the alcohol mixture. I suspect that getting much above 
90% doesn't yield significant improvement in evaporation time. But we 
obviously have examples here where using something higher than 90% would 
be more desirable if you are not spot cleaning and don't want to wait.


Regards,

John AC0ZG

On 7/14/2021 5:41 PM, brianpepperdine brianpepperdine wrote:

I have no idea, obviously, what the USA market offers, but here we get 99.9%
(not 90%) isoprophyl alcohol. So much the better re. less residue of course.
Admittedly it was a bit hard to get at the beginning of the pandemic but that
seemed resolved with a couple months.

Ages past I had to ask the pharmacist for it and he decanted it from a large
bottle behind the counter into a small bottle for me.
He said you are either diabetic or into electronics, as I think that was the
main call for it. Largely they sold the smaller percentage stuff for rubbing and
sores.
Here is is stocked on the shelf now already packaged, in the first aid area
(right next to the alcohol swabs).

If hard to find you might ask your pharmacist.. its possible they have it behind
the counter for the real need purposes, or he can suggest if he can order-in.
You never know. I doubt at this time now that there is any real supply shortage,
IMHO"

Brian VE3HI  Toronto
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] Broke my K2 :(

[John Marvin]

Hopefully this is obvious, but make sure you are using the 90-91% 
isopropyl alcohol, and not the 70% variety. It can still be hard to get 
the 90% variety these days.


73,
John  - AC0ZG

On 7/14/2021 4:41 PM, Peter Eijlander (PA0PJE) wrote:

Yes Jerry, isopropyl alcohol does this!
I once cleaned a working print of a GPS receiver with isopropyl 
alcohol and it stopped working. Letting it be and trying it again next 
day turned out it worked perfectly again.


 From then on I leave a PCB to rest after cleaning to have the IPA dry 
out completely...


73,
Peter - PA0PJE





Op 14-07-2021 om 14:54 schreef jerry:

Actually, I suspect that when I scrubbed it with isopropyl alcohol, it
shorted out

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org 



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] What I need and meant

[John Marvin]

Running a full Windows OS under emulation on a Raspberry Pi, just to run 
one app is not a very good idea (as Adrian pointed out).


An alternative would be to run QEMU on the Pi, which provides an x86 
execution environment, and then try to get the N3FJP software running 
under Linux Wine (Wine provides versions of the Windows libraries needed 
by a  Windows app that translate to linux libraries / system calls). I'm 
not saying this is an easy path to follow, but there are a lot of people 
who have succeeded doing this. The N3FJP software is simple enough that 
it would probably work reasonably well. Getting all the pieces in place 
though will be difficult, unless you can find an appropriate canned 
image for the RPi that already has Wine and QEMU installed properly.  
Here's a two year old one for a RPi 3 running Debian Stretch:


https://sourceforge.net/projects/pi-qemu-wine/

People have been successful getting WIne running on Qemu on the RPi4 and 
newer Linux distributions, but I haven't seen a canned image for use by 
those who are not linux / QEMU experienced users. Here's a link to a 
tutorial that was used to create the above canned image (including a 
youtube video).  People have adapted that to make things work on the 
RPi4, etc :


https://www.novaspirit.com/2019/04/15/run-x86-arm/

There used to be a (non free) x86 environment for the Raspberry Pi 
called Exagear Desktop, but that is no longer available (but there are 
plenty of articles on the web giving instructions on how to run Wine on 
Exagear Desktop, so don't go down that rathole).


Anyway, there's a lot more web pages that discuss this, and perhaps 
there is one out there that is more recent that would allow you to get 
it all running on a RPi 4.


73,

John, AC0ZG

On 6/30/2021 10:38 AM, Mike Short wrote:

Atomic Pi is an alternative for this. I have one running Win10 and logging
app. 12v power.

On Wed, Jun 30, 2021 at 11:51 KJ7SOY  wrote:


Unfortunately that’s a terrible idea. I’ve been using Pi’s for 8 years. I
currently have 23 of them deployed managing our home automation,
surveillance systems, and other assorted tasks. 12 are in a rack in my
rackmount cabinet and the rest are deployed around our property (6 acres).

The two things they do NOT do well are run Windows and run Android. I’ve
tested multiple times, on multiple Pi’s (up to and including the 8GB PI 4)
with every variant that has ever claimed to run on the Pi. They don’t.
Period. Either they lack drivers, or they run slower than molasses in a
freezer. They have NEVER functioned, and given the Pi’s architecture and
their library demands likely never will. Virtualization makes no
difference. They just don’t work.

Please don’t waste your time trying this. It’s truly not worth the time
you’d spend getting it installed.

73
-Adrian
KJ7SOY





__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] HOA antenna restrictions

[John Marvin]

Luckily for you, they were not aware of the FCC OTARD rules which 
absolutely override covenants with respect to small satellite antennas, 
rooftop TV antennas, and wireless ISP/cell dishes/antennas. However, the 
OTARD exemption does not cover ham radio antennas (there have been bills 
to try to add an exemption for them, but none have succeeded). No HOA 
has succeeded in challenging these rule, although many have tried.


John, AC0ZG

https://www.fcc.gov/media/over-air-reception-devices-rule


On 6/28/2021 8:32 PM, eda...@aya.yale.edu wrote:

I confess to having done something similar, though I used a jiu-jitsu move
rather than rational argument as Phil did.  Within five or so years of
moving in I became the President of the HOA (because no-one else wanted it)
and, like Phil, after six or seven years of it (because still no-one else
wanted it) I quit and wouldn't do it again for love or money either.
However, during my tenure I pointed out at a meeting of the HOA that our
covenants had an absolute no-external-antenna rule, yet about half of the
garages in the association had two-foot diameter satellite TV dishes on the
roof (this was the early 2000s.)   Under the existing covenants, they would
all have to go.  Either that, or to protect them we could amend the
covenants by just deleting the no-antenna rule entirely.  The vote was
unanimous.

Ted, KN1CBR

-Original Message-

Date: Mon, 28 Jun 2021 15:25:15 -0700
From: Phil Kane 
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] HOA Crap
Message-ID: 
Content-Type: text/plain; charset=utf-8; format=flowed

That's where I was when we moved into a brand-new condo in California
in1988.  At the time the "Board" was the developer, and I scored a
meeting with their VP-engineering.  Spoke to him engineer-to-engineer
and got approval for several VHF/UHF antennas on the roof.  When the
Board was turned over to the owners I made sure that I was on the new
Board and I drafted a Memorandum of Ratification that covered more
antennas including a long wire with secured access to the roof.  The
other two Board members were too dumb to do anything but approve it.
Even after I was off the Board in a power play the antennas stayed there
until we moved in 1999.  Note - I have no intention of serving on a
Condo or HOA Board again even for a sack of gold.


73 de K2ASP - Phil Kane
Elecraft K2/100   s/n 5402

  From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon



--


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] FAA-Approved Antenna authorized by HOA

[John Marvin]

Note, I intended to make a similar joke, until I realized Jerry messed 
up the setup by actually including the antenna height in his post 
(unless he has a very loose definition of approximately). :)


John, AC0ZG


On 6/28/2021 4:33 PM, eda...@aya.yale.edu wrote:

I believe the FAA does need to approve the structure and lighting on
antennas higher than 200' AGL.  Or some such rule, depending on how close
the structure is to an airport.

  


So Jerry's must be a vertical dipole for 160M.  I'm impressed.

  


Ted, KN1CBR

  

  


Date: Mon, 28 Jun 2021 13:45:27 -0700

From: Dennis Moore mailto:den...@mail4life.net> >

To: jerry mailto:je...@tr2.com> >,   Elecraft
Reflector Reflector

mailto:elecraft@mailman.qth.net> >

Subject: Re: [Elecraft] HOA Crap

Message-ID: mailto:ce6cc6e2-6721-978e-b0df-6f0b0437a...@mail4life.net> >

Content-Type: text/plain; charset=utf-8; format=flowed

  


FAA-licensed? I'd request a new letter with FCC-licensed.

  


Dennis NJ6G

  


On 6/28/2021 12:27, jerry wrote:


All,
? Just had to share this snippet from a recent letter I received from
my HOA:
"Dear Homeowner:
? Your architectural plans, to install a vertical antenna for
Amateur Radio, approx 25 feet tall, mounted on existing pool solar
heating array, on a hill behind the house.? Used for FAA-licensed
amateur radio activities.? This antenna predates the formation of the
HOA [...].?? Your plans have been approved"
?? The secret?? The Board has the power to approve pretty much
anything, regardless of the CC&Rs.? And I'm on the Board.? I'm also on
the architecture commmittee.
? When I moved here in 2011, there was no HOA.? But it was in the
deed.? When the HOA was formed, I ran for the Board, got elected ( not
much competition ), and made d*mn sure I was on the architecture
committee.
 - Jerry KF6VB
  

  


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] Oscilloscope recs

[John Marvin]

Well, if budget permits, I would recommend the Keysight DSAZ594A. This 
would be especially useful on some of the higher amateur radio bands.


73,
John AC0ZG

On 12/9/2020 7:31 AM, inventor61 wrote:

I would be remiss, as a Keysight employee, to not mention the option of
going with something like the Keysight model EDUX1052A (available from
numerous vendors such as Mouser) or, if the budget permits and one wants to
do things like sweep filters, have an integrated bench signal generator,
serial data protocol analyser, etc., the DSOX1204G (which I have).

Keysight is the test equipment company formerly known by many as
Hewlett-Packard, today headquartered in Santa Rosa, CA.

Steve KZ1X
Celebrating 21 years of daily Elecraft reflector use today
Owner / Builder of K2 #771,
The World's Most Experienced Elecraft
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com 

Re: [Elecraft] K4

[John Marvin]

I guess it must be "morning" on the east coast. The K4 is now officially 
up on the front page of the Elecraft website, and you can now submit 
pre-orders again, for those who are anxious to do so.

73,
John
AC0ZG

On 5/16/2019 1:23 PM, Wayne Burdick wrote:

Reporting live from Chicago, en route to the Hamvention Yes, Schrödinger's 
cat is out of the bag :)

Apologies for the web page glitch. Someone found it before it was ready. It’ll 
be back up tomorrow morning.

If you managed to place a reservation already, please email sa...@elecraft.com 
to confirm.

More later—

Wayne
N6KR
  




elecraft.com
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] K4 price?

[John Marvin]

Well there is this interesting quote on the translated swiss website:

The prices of the device, its options and the accessories have not yet 
been fully defined.The statement from Eric Swartz, co-founder and 
owner of ELECRAFT reads:/"The K4 will be cheaper than the K3S with 
comparable equipment"./Detailed pricing information will follow on our 
site as it becomes available.

73,
John
AC0ZG

On 5/16/2019 2:35 PM, Wayne Burdick wrote:

It’ll all be on our website tomorrow.

Not your grandpa’s SDR :)

73,
Wayne
N6KR


elecraft.com

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Elecraft] WWV 100th Anniversary Event

[John Marvin]

Just a quick note, WWV is celebrating 100 years on the air this October, 
and NCARC (I'm a member) is sponsoring an event with NIST on the WWV 
property from 9/28 - 10/2. More information can be found at 
http://wwv100.com.


So, how is this Elecraft related you might ask? Well the club is still 
looking for operators,  and Elecraft is a sponsor for the event, 
providing four KX3's and four KPA500 amplifiers for the event (Thanks 
Wayne and Eric!). So if you decide you want to take a trip to Fort 
Collins to help out, you may be very familiar with the equipment used!


73,

John Marvin

AC0ZG

P.S. I am just an NCARC member, and am not a contact person for this 
event. I will be a volunteer, and hopefully an operator.


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] KPA1500 Caution

[John Marvin]

In general, the quality of service that you perceive from the USPS, UPS 
or FedEx is almost completely due to the behavior of your local delivery 
person. None of the carriers treat your package with kid gloves, and a 
lot of it is automated such that they really don't pay any attention to 
"Fragile" notices, etc.  Most of the time if your package is damaged 
before your local delivery person gets their hands on it, it is due to 
low quality packing materials used by the shipper.


Judging the overall nationwide quality of the USPS, UPS or Fedex based 
on what you see from your local delivery people doesn't make much 
sense.  That's why when people get in this type of discussion you hear 
about all the nightmares of a particular service from one person, and 
all the kudo's of the same service from another person.


I happen to be lucky in that my local delivery people for all three 
services vary from very good to outstanding (my USPS carrier, when 
delivering a package, comes to the door with the rest of my mail, and 
rings the bell, waiting for me to come to the door. If I'm not home he 
places the package behind a post near the front door, and delivers the 
mail to the street mailbox). But friends living in the same town with 
postal workers working out of the same post office facility, have lots 
of bad experience with their carriers, and therefore hold a very 
prejudicial view of the USPS.


Now there are other services that are terrible, and the problems occur 
throughout the system.  Amazon Prime occasionally uses a service called 
Ontrac, which ships to 8 states in the west. At least here in Colorado, 
they are reprehensible, and border on fraud when it comes to making 
their shipping comitments. Based on online reviews, I don't think 
they're any better anywhere else.


73,

John
AC0ZG
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] 32 bit Elecraft Utility Apps

[John Marvin]

Unless you ran it under emulation (e.g. wine or something like that), I 
think you are misremembering. KX3 utility is currently only available as 
X86 32 bit application. It can't run natively on a Raspberry Pi.


73,
John
AC0ZG

On 4/12/2018 10:43 AM, Thorpe, Jeffrey wrote:

I don’t remember - I’ll try to look at it tonight and see how. I don’t think I 
had to do anything goofy...I’m running the latest Raspbian also.

Jeff - kg7hdz

On Apr 12, 2018, at 9:18 AM, James Austin 
mailto:ka2...@gmail.com>> wrote:

I just downloaded and tried to run it on a Pi running the latest version of 
Raspian got the error I expected.

pi@raspberrypi:~/kx3util_1_16_6_25 $ ./kx3util
-bash: ./kx3util: cannot execute binary file: Exec format error
pi@raspberrypi:~/kx3util_1_16_6_25 $

How did you get it to run?

Jim/KA2RVO




__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] Shack project

[John Marvin]

Charlie,

Since the KPA100 is an add-on for the K2, I assume that you mean the 
KXPA 100. Why can't you drive your 811 with a KXPA100?


73,
John
AC0ZG

On 3/2/2018 7:41 PM, Charles Carlon wrote:

Time to update and organize the Shack. I currently have

Icom 756 Pro III
Icom 7100
KX3 with Panadaptor
  Ameritron 811

Work SSB and digital modes
QRP with the KX3 battery and solar
Not a contestor and not good enough yet for CW

Upgrade options
Sell 7100 and buy KPA 100 or Icom 7300
Sell 756 and buy KPA 100 or Icom 7300
Sell both and buy both
Really love the KX3 and Px3. The KPA 100 would be good fo field day and field 
setups but would not be able to connect to the 811
The 7300 would add the panadaptor and be able to connect to the 811 but not 
have the portable options of the KX3

What do I loose if I give up the 756?

Charlie
N7CAC

Sent from my iPad
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] PTT switch for K3

[John Marvin]

Thanks for this idea. I prefer a foot switch, and I've already had one 
of the Heil switches die on me in less than 2 years of use. Right now 
I'm using one I got from Radiodan.com. The owner is a member of my club, 
and I bought it at our annual HamFest. It looks to be of decent quality, 
but I don't know his source.  Anyway, if this one dies, I am definitely 
going to try a sustain pedal. They typically have a switch which 
switches the operation from on/off to a variable resistance (depending 
on what you are using it for). It should work fine for PTT operation in 
the on/off mode, and they are fairly rugged. I may have to try it soon 
just to see how one would feel in actual operation.


73,

John
AC0ZG

On 1/7/2018 1:01 PM, Alan wrote:
If you don't want to build something, check out a music store.  The 
kind of foot switch bands use is very rugged and reliable.


Alan N1AL


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] OT -- Ham radio operators contribute to protecting the Earth

[John Marvin]

Perhaps you are confusing VLF with VHF? The article talks about VLF 
transmissions. VLF is 3-30 Khz. There are no ham bands in that range.


73,

John
AC0ZG

On 5/18/2017 6:23 PM, Phil Hystad wrote:

I thought some other ham operators might like to read how they are helping
to build a protective bubble around the Earth.

https://www.theatlantic.com/science/archive/2017/05/wow-guys/527193/

73, phil, K7PEH

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] A little theory.

[John Marvin]

Sorry, it is you are confusing the two. It was Feynman on both counts. 
Sagan would have been 8 years old when the Manhattan Project was 
started. Feynman was also on the Rogers Commission that was tasked with 
investigating the Challenger disaster (Carl Sagan was not involved).


73,

John
AC0ZG

On 4/18/2017 1:50 AM, David Woolley wrote:
I believe people are confusing Feynman and Sagan.  I think it was Carl 
Sagan who demonstrated the sloppy practices with combination locks and 
did the Challenger enquiry.


I did read some of Feynman's lectures, in high school.



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] Amplifier thoughts

[John Marvin]

Put me down as a vote against a built-in antenna tuner. I prefer a 
separate external tuner that integrates well with the amplifier. It 
allows for a lot more configuration flexibility.


73
John
AC0ZG

On 3/28/2017 5:00 PM, Paul Van Dyke wrote:

Ralph Parker said my list.

1500w output, 160 - 6m.
2 inputs.
4  outputs (Manual switching is OK).
Built-in antenna tuner (good for 3:1 SWR).
Reasonably quiet fans.
Separate p/s, or remote control head (space considerations.  :-)

Paul. KB9AVO​

On Mar 28, 2017 4:40 PM, "Ralph Parker"  wrote:


I better post this before I'm too late.

I'd like:
All the features of my KPA500, plus
1500w output, 160 - 6m.
2 inputs.
2 outputs (or more. Manual switching is OK).
Built-in antenna tuner (good for 3:1 SWR).
Reasonably quiet fans.
Separate p/s, or remote control head (space considerations).
(I understand the difficulty of getting high power from the p/s to the
PA.)
I don't expect to carry it around, so weight is not a problem for me.
Expeditions can use the KPA500 :-)

When this amp is available, I'll sell amplifiers Ac and Am and buy one.
I'm keeping my KPA-500!

Ralph, VE7XF

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to pvandyke1...@gmail.com


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] Linear thoughts

[John Marvin]

I want to echo that a KPA-1500 be the same as the KPA500 in terms of 
ease of use and interface, solid state, QSK switching, etc.


Some of my points:

Some have said "at least 1000W". In my opinion, that is not a big enough 
step above the KPA500, but some will make the case that 1500 isn't 
either, but at least it is the max allowed. If you're going to sell an 
amp above the KPA500 make it full legal limit.


Leverage what you can from the KPA500, but at the same point, the KPA500 
design is getting a little old. A lot has happened in high power solid 
state RF electronics since then. I would prefer that the amp be based on 
LDMOS RF Power transistors. Perhaps the MRF1K50HR5 from NXP 
Semiconductors should be considered. LDMOS is known for great linearity 
and the latest devices are pretty rugged.


If you do invest in a newer design, consider some backwards leverage 
from the KPA1500 (if that is what you call it) to the KPA500, i.e. an 
updated KPA500 V2 that leverages some of the new design and perhaps 
makes supporting the two amps easier.


I may never buy a KPA1500, but I once said that I would never want more 
than 100W when I bought the KXPA100, but now I own a KPA500/KAT500!


73,
John
AC0ZG

On 3/24/2017 4:11 AM, Arie Kleingeld PA3A wrote:

Besides the usual things nearly every other hi-end linear has:
- tuner built-in as an option
- really light weight
- at least 90% efficiency
- one, max 2 antenna ports

(these fit into the portable rig philosophy of Elecraft)

73
Arie PA3A
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] KPA500 Power Supply Environmental/Ergonomic Issue

[John Marvin]

I know this thread is supposed to be closed now, and hopefully this 
would be obvious, but you should also wait for the fans to stop before 
"pulling the plug". You should always turn the KPA500 off with the 
switch (or the KPA utility) first, wait for the fans to stop, then you 
can use the back switch or a power cord switch.


73,

John
AC0ZG


On 2/1/2017 5:25 PM, Kevin wrote:
Get ye to the local hardware emporium and buy the $10 power strip with 
a switch. Plug the KPA 500 into said switch. When done using the amp 
use the front panel switch to shut it "off" so it saves settings 
properly then hit the switch on the power strip. Viola! You've saved 
six watts and won't end up on some ridiculous website as a planet hater.




__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] KPA500 Power Supply Environmental/Ergonomic Issue

[John Marvin]

Dave,

Perhaps you want to turn on your amp manually each time. But what you 
may have missed is that 7 watts is doing more than just detecting 
whether the power switch on the front is used or not. When the KPA500 is 
"off" the RS-232 connection on the back is still live, and there is a 
processor in the KPA500 that is monitoring that connection. You can 
remotely turn on the KPA500 using the KPA utility.  For those whose 
KPA500's are in a remote location, or just in an inconvenient location 
(i.e. not adjacent or within easy reach of your operating position), 
this is a very nice feature. It would be more than just the "power 
supply system" that would need to be redesigned.


73,

John
AC0ZG

On 1/31/2017 8:45 PM, Dave AD6A wrote:

I recently added a KPA500 kit for my home station. It went together just
fine, and overall I love it.

There is one thing about the way it works that bugs the engineer and
environmentalist in me.

  


Before I bought the PA, I thought I'd be able to turn it on/off entirely
using the ON button on the front panel.

I thought that maybe there was a supercap or backup battery that kept the
button's electronics alive to perform the ON button function (like TV's have
in them).

However, it doesn't work like this. In order to turn the PA off completely,
you have to turn off the main power switch on the rear panel.

  


The front panel ON button powers up the PA from what looks like a cold
state, however, my measurements are as follows:

  


1.  With the main power switch on the back panel turned OFF, the PA
takes no power at all (0.0W)
2.  When you turn the main power switch on the back panel to ON, the PA
draws 6.9W continuously from the 120V AC power supply
3.  When you press the front panel ON button, the PA turns "ON" and
takes around 13W (measured) in STBY mode

  


My home station line up (K3s, P3, 2x SP3, KPA500, KAT500) sits on a large
operating desk with a shelf unit that I build above the station. My computer
monitors sit on the shelf above the radios.

There is only just enough height clearance (about 2.5") between the top of
the KPA500 and the underside of the shelf to allow me to put my hand over
the top of the PA to reach the main power switch.

It's fiddly but I can do it, it's just that it's a major inconvenience not
being able to turn the KPA500 truly off from the front panel.

  


Why is the KPA500 designed this way?

In all good conscience, I can't live with the PA consuming 7W all day, every
day - that's incredibly wasteful.

I suppose I could put a more-easily-reachable external AC power switch on
the side of my shelf unit to cut power to the whole desk, but that'd be
ugly.

I'd prefer that either a) the KPA500's main power switch was on the front
panel, or b) the power supply system was redesigned so it only takes a few
microwatts when power is applied but the ON button is OFF (not pressed, or
pressed an even number of times).

  


Comments? Ideas?

  


Cheers,
Dave AD6A




__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

[Elecraft] Operating with a KXPA100 driving a KPA500

[John Marvin]

Hi,

I've been operating with an OpenHPSDR Hermes driving a KXPA100 for quite 
a while (I ordered my KXPA100 on the day that Elecraft started taking 
orders for it). I just ordered a KPA500/KAT500 combination for higher 
power operation. My plan is to drive the KPA500 from the KXPA100. I know 
that others have done this, but I haven't seen many details.


Since I have an early KXPA100 (Serial #302), it doesn't have the extra 
PTT protection, but I believe that is not a problem with the KPA500, 
since it uses a 5V keying circuit. So I plan to "Y" the PTT connection 
from the Hermes (actually there's some custom mods to provide a little 
more protection for the Hermes on the PTT line, and was also a required 
change to properly key the KXPA100) that currently goes to the KXPA100 
and connect that also to the KAT500. Then I will connect the PTT out 
from the KAT500 to the PTT in on the KPA500. I'll operate the built-in 
KXAT100 in bypass mode when operating with the KPA500.  Are there any 
potential issues I should be looking for? Any timing adjustments that 
can be made?


I know I'll have to do some calibration with the HPSDR software to make 
sure that I don't drive the KXPA100 beyond 30-40 watts when it is 
driving the KPA500. I don't have any way of doing anything with the ALC 
output from the KPA500, so I just need to make sure I don't get it to 
that point.


Eventually I plan to do some better software integration to take better 
advantage of the band switching support, but I've meant to do that for 
some time with the KXPA100 and haven't gotten around to it (so much 
software to write, so little time!). So meanwhile I'll be operating with 
a fairly basic connection setup.


Some questions:

1) Since I don't have a K3, I currently have no need for the AUX 
connector that would normally go between the K3 and the KAT500. Is there 
any advantage/reason to connect an AUX cable between the KAT500 and the 
KPA500? If the KAT500 is basically just looking at the signals from the 
K3 without ever driving anything for the connection to the KPA500, then 
this wouldn't make sense. But if there is any active info being passed, 
perhaps it would make sense? For example, while the KAT500 is tuning it 
can drop PTT to the KPA500, in which case the KPA500 is probably not 
determining the transmit frequency, whereas the KAT500 is looking at 
that. It could tell the KPA500 the correct band rather than having the 
KPA500 determine that by itself. Probably not that important, but 
perhaps I'm missing something.


2) Is there any indication in the KPA500 LCD screen when the ALC is 
triggered? How about the KPA500 utility? I haven't seen anything in the 
documentation, but perhaps I missed that.


3) I ordered both the 120V power cord/fuses and the 240V power 
cord/fuses.  I'm going to start with 120V operation, but I can wire the 
study (my "shack") with a 240V outlet if necessary.
I'm not even sure I can currently dedicate a 120V circuit to the amp, so 
I might have to move to 240V fairly quickly (If I'm going to wire a new 
circuit, might as well be a 240V circuit). For

those running their KPA500's on 120V how well has that worked for you?

4) Anything else that I might have missed? I'm especially interested in 
any operating procedure tips from those who are running with a KXPA100 
driving their KPA500.


5) I read about some earlier issues with the KAT500/KPA500 when tuning, 
i.e. the KPA500 would fault during the tune in some cases. I believe 
that has been fixed in firmware, i.e. I haven't seen any recent reports 
related to this. Can I assume this issue is no longer present?


73,

John
AC0ZG



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] OT: Changes at WWV, WWVB

[John Marvin]

There's some wrong information being propagated here. Somehow the 
failure of frequency comparators and/or frequency standards that were 
based on doing a PLL with the CARRIER of the WWVB signal is being 
extrapolated to the failure of all Radio Controlled Clocks which do not 
track the carrier but instead read the time code that is imposed on that 
carrier. This is completely wrong.


The new Phase Modulation signal is imposed on top of the legacy PWM 
signal that has been broadcast pretty much since the beginning. Radio 
Controlled Clocks that just read the PWM encoding should not be affected 
by the phase changes of the PM signal, and will still work as before. 
The reason that some clocks may only get a lock at night is purely an 
issue of propagation, and will almost certainly be true for clocks 
located in the eastern part of the US.  In fact, that is the primary 
reason for adding the PM signal, since it can be decoded at lower signal 
strengths than the PWM signal can be decoded.


However, devices like the HP-117 and Spectracom 8170 performed a PLL on 
the carrier of the signal, since the carrier frequency itself is very 
accurate. These are broken by the addition of the PM signal, since it is 
flipping the phase of the signal by 180 degrees periodically. None of 
the cheap consumer "Atomic Clocks" do this (phase lock the carrier). 
People have developed external circuits that "reclock" the WWVB signal 
and allow these type of devices to continue to work.


Also, WWVB did shut off the PM part of the signal for a few hours every 
night during a transition period that ended in May 2013. That is no 
longer happening, but again this only affects phase locking receivers. 
Specifically LaCrosse states clearly on their website that their clocks 
are not affected by the addition of the PM signal.


Finally, I don't think there any commercially available clocks, at least 
at the consumer level, that support the new PM signal at this time. The 
decoder is patented, and I believe chips that support it are either 
still in development or only recently released. I'll try to do some more 
research regarding this.


Regards,

John
AC0ZG

On 11/28/2014 1:18 PM, Ken G Kopp wrote:

I have a long-time close friend who's retired from
the NBS in Boulder and was the project engineer
on the NBS #7 cesium standard.  After the recent
reflector postings about  WWV / WWVB I thought
I would get first-hand recent information from him.

The GPS satellites all carry on-board cesium
standards that are synchronized with NTIS, and
because of changes (below) to WWVB, cell phones
remain the most accurate source of time for most of us.

All the HF transmitters at Ft. Collins are the same TMC
units that were put in service when the facility was built.
The 2.5 and 20 MHz transmitters run at lower power due
to propagation considerations.

The time and other station-related voice info is sourced
on site in Ft. Collins, and the various propagation and
weather info comes from various "dial in" land-line
sources. Hence the widely varying quality of these
announcements.  I forgot to ask about the individual
who made the voice recordings ...

Here's the most important info  as of about a year
ago the modulation scheme on WWVB (60 kHz) was
changed (phase reversal each minute) and this has
rendered most of the end-user equipment inoperative.
Most (all ?) tracking receivers like the HP-117's are
now useless without extensive modification.

Most of the "atomic" clocks now in use ->do not<- synch
to the current modulation scheme on the 60 kHz signal.
This will explain the differences in displayed time on
supposedly identical clocks and how some appear to
not be getting sufficient enough signal to synchronize.

He offered no comment on how to locate "consumer"
clocks that -do- respond to the "new" modulation scheme.

The 60 kHz transmitter is indeed an ex-LORAN C unit,
and because of the higher power of the "new" transmitter
the antenna system was rebuilt using material from the
LORAN C site.

The 20 kHz transmitter was "home made" by NBS staff
at the old Beltsville, MD facility and moved to Ft. Collins.
There is no longer an antenna for this transmitter and it
will not return to the air.  Trivia:  The antenna was of
such high-Q that a near-by thunderstorm system would
often detune the system and cause the overload protection
to trip the transmitter off.

He suggests that a visit to the NBS website would be
"informative".

73

Ken Kopp - K0PP
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
H

Re: [Elecraft] KXPA100 f/w 1.28 now production released

[John Marvin]

Wow Matt, Thank you, Thank you, Thank you. I've been off the air since 
last Saturday trying to diagnose my problem. I had problems last 
Saturday and people were saying my signal was breaking up.  I originally 
thought there was something wrong with my transceiver or settings. I 
carefully traced everything and monitored output from the transceiver 
and decided that although some settings could be improved (which I did) 
that wasn't the reason. I then thought that perhaps the issue was the 
1/2" of ice I had on the antenna that night, so after checking 
everything else I decided to go back on the air tonight. And sure enough 
my signal was breaking up again, even though it hadn't earlier during 
testing. This time I even though I was wearing headphones and with the 
background static I thought I heard a click from the amplifier. I was 
(still am!) on a net at the time (HHH Net), so I qsy'd down 4 Khz and 
did some testing, and I noticed the SWR kept going from 1.0 to much 
higher values, with the amp kicking out.


I then remembered reading your email. Went back and read it again and 
wondered if I was experiencing the same thing you were. Sure enough, 
moved back to 1.09 and the problem is gone.  Of course, there have been 
some fixes after 1.09 for other problems I've experienced, so hopefully 
Elecraft will get this one fixed soon.


Thanks again!

John

On 5/16/2014 10:06 PM, Matt VK2RQ wrote:

Elecraft is right on top of it; I'm also confident we'll have a solution fairly 
soon.

73,
Matt VK2RQ


On 17 May 2014, at 1:52 pm, Ron Cowherd  wrote:

Yes, I have also had similar problems with the KXPA100 (SN#0876)and have 
already composed and sent a letter to support.  The letter is much too detailed 
to reproduce here but I also suspected a firmware glitch.  My unit was working 
flawlessly until the upgrade.  I'm sure the problem will soon be solved.

73, Ron K4GYD

Sent from my iPad


On May 16, 2014, at 6:56 PM, Matt VK2RQ  wrote:

How are people finding this new firmware?

I've been having problems recently with my KXPA100, where it intermittently 
shows high SWR for a brief moment, and then either recovers or puts itself in 
bypass. At first I thought I had an issue with my antenna, but I discovered it 
was happening with a dummy load too. It mostly happens on SSB, but it happens 
to a lesser extent CW. It also happens with both my KX3 with integrated cable, 
and with my K2 using the keying line. I pulled the amp apart, looking for poor 
connections and dry joints, but no success there. By gently blowing across the 
mike, I was able to get it into the failure mode, and stay there. The SWR 
bridge in the amp was reading high. I had a crossneedle SWR meter between the 
radio and the amp, but as I blew progressively harder into the mike, the SWR on 
the meter was low. Then, once the power applied reached a certain level, the 
amp would come good again. This made me suspect whether the band auto-sensing 
may have been switching in a wrong LPF?

Then last night, I reflashed the amp with release firmware 1.28, but still had 
the problem. Then I downgraded the firmware on the amp from 1.28 to 1.09, which 
was the release my amp was shipped with. I haven't observed or been able to 
reproduce the problem since. This is now leading me to suspect a possible bug 
in the 1.28 firmware?

I'm wondering if anyone else may have observed any strange glitches with the 
1.28 firmware?

73, Matt VK2RQ


On 3 May 2014, at 2:14 am, Eric Swartz - WA6HHQ, Elecraft  
wrote:

KXPA100 Production Firmware MCU 1.28 has been released to production status and 
is now shipping.

Important: This version of firmware has new features that require the very 
latest KXPA100 Utility.

We recommend all KXPA100 owners upgrade to the latest KXPA100 utility and to 
KXPA100 MCU 1.28.


Some of the Key Changes in this release:

- Better tolerates forward and reflected power overshoot for brief periods to 
support external antenna tuners. Use approximately 10-20 watts of KXPA100 
output when tuning.

- When the attenuator is acquired because of SWR or high reflected power, 
release attenuator immediately on next key up if SWR has been reduced to 3:1 or 
less.

- Update band voltage tables for ICOM 703 and Yaesu FT-817

- Reduce power required for ATU tune.

- Add per-band Antenna configuration (requires the new KXPA Utility for user 
interface)

- Improved RS232 handling for 3rd party applications. (Ham Radio Deluxe v6.2, 
PigKnob, etc.)


73,
Eric
elecraft.com

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to matt.vk...@gmail.com

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/li

Re: [Elecraft] Fake FTDI chips

[John Marvin]

Joe, I think you read Ross's post differently than intended. I don't 
think Ross was suggesting that Elecraft do their own USB to RS232 
converter chip or provide a native USB interface with custom Elecraft 
drivers (although there would potentially be other advantages to a true 
USB interface, the driver challenge you mention would probably outweigh 
those advantages). He was suggesting that Elecraft use a standard (e.g. 
FTDI) converter chip inside the box (I'm not sure a retrofit would make 
sense, but this would be a change going forward). From the perspective 
of the computer, it would not see anything different from an external 
converter, and you would use the same drivers.


The supposed advantage is that by buying the converter chips directly 
Elecraft would be in a better position to ensure that the chips weren't 
counterfeit. However, since Elecraft is supplying converters to their 
customers and is buying them in bulk, it would seem to me that they may 
be able to get most of the way there by working with a reliable supplier 
and doing the necessary checking to make sure that the converters they 
are buying don't  contain counterfeit chips.


John
AC0ZG

On 4/14/2014 1:00 PM, Joe Subich, W4TV wrote:


Then _Elecraft_ would need to worry about continuously updated and
*signed* drivers for Windows (including Windows 95, 98, 2000 and XP
compatible drivers 15 year after the operating system is no longer
supported), OS-9, OS-X, and 57 varieties of LINUX.

Far better to stick with RS-232 and leave the _USER_ be responsible
for his on computer interfacing.

73,

   ... Joe, W4TV



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] Elecraft SSB net

[John Marvin]

I logged in for the first time, even though my only significant piece of 
equipment is the KXPA100 amp. Band conditions weren't great, so it's 
possible you just couldn't hear most of the people loggin in. Obviously 
you didn't hear the net control or the primary relay. I am surprised you 
didn't hear anyone logging in. My guess is that if you try again next 
week you'll have better luck, assuming band conditions are better.


John
AC0ZG

On 4/13/2014 7:58 PM, Slava Baytalskiy wrote:

How does this net work?
I tried to get on today, at 2 PM EST (1800Z).
I heard almost nothing. Some random people calling CQ and what not.
No net control.
Is there a particular protocol that this net follows?
Was it even on today?
Just curious...

Slava B
W2RMS

On Apr 13, 2014, at 1:31 AM, Phil Shepard  wrote:


The weekly SSB net meets tomorrow (4/13/14) at 1800Z on 14.3035 MHz.  I’ll be 
the NCS from Oregon.  See you there.

73,
Phil, NS7P


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to sla...@nullserv.com

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] KX3-2M module?

[John Marvin]

Am I reading something wrong? You say that you would need +/- 144 Hz, 
and Wayne is saying that you can get +/- 10 Hz with the extended 
temperature compensation. That seems that it would be good enough.


I'm also seeing all this complaining about stability, and the only 
counter example appears to be +/- 1700 Hz at 1296Mhz for a TS2000, which 
doesn't strike me as all that good either.


Is the real issue that there is no support for an external reference?

John
AC0ZG

On 4/8/2014 6:02 PM, Walter Underwood wrote:

The specs for frequency stability are not good enough for the JT65 modes (+/- 1 
ppm typical over 0-50 C). On 2m, that would be +/- 144Hz. The extended 
temperature compensation improves that, but it will never be as stable as a K3 
with an external reference.

Did you expect it to perform much, much better than the specs?

The FT-817 specs are: ± 4 ppm from 1 min. to 60 min. after power on. 25° C: 1 
ppm/hour

wunder
K6WRU

On Apr 8, 2014, at 2:58 PM, "Dave"  wrote:


The more I see, the more I realise that the promised 2M unit is going to be a 
very poor option for people who use VHF and UHF seriously.

I have re awakened my use of HF, but I did buy the Elecraft KX3 with the 
promise of a decent 2M option.

Where do I apply to return my KX3 for a full refund ?

Dave (G0DJA)

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] SSB net cancelled for Sunday, March 30, 2014

[John Marvin]

Just a thought ... perhaps you should consider having an alternate 
frequency on one of the WARC bands for major SSB contest weekends (e.g. 
somewhere on 17m).


John
AC0ZG

On 3/29/2014 9:33 PM, Phil Shepard wrote:

The WPX Phone contest running this weekend will make operating our net 
challenging, so let’s take the week off.  If we had more big gun powerhouse 
stations, we might be able to stand up to the QRM. We have a few, but we also 
have a lot of QRP check-ins.  Have a great week and we’ll see you next Sunday.

73,
Phil, NS7P

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to jm...@themarvins.org


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to arch...@mail-archive.com

Re: [Elecraft] [KX3] Re: KXPA100 SN 707 Total Frustration with this Amp

[John Marvin]

The suggestions to try a dummy load first are right on. Do you have the 
built in ATU, or just the KXPA 100? If you have the ATU I would try both 
antenna outputs.


If I had to guess what the problem is I would guess that you didn't seat 
the antenna connector from the back panel correctly to the atu board (or 
main board if you don't have the ATU) when you were assembling the amp. 
This is most likely to be the cause if you still get high SWR faults 
when attempting to transmit into a dummy load.


John
AC0ZG

On 3/9/2014 7:07 PM, rldil...@aol.com wrote:


The high SWR happens even when the AL80b or Palstar tuner is not 
connected. In other words when coax from the kpxa100 goes direct to 
the K4KIO Hexx beam with nothing in between to confuse the amp except 
a barrel connector.
Yes you can drive a larger amp with the kx3 and KXPA100. It is covered 
on page 19 of the manual in paragraph titled Keying an External 
Amplifier.

-Original Message-
From: Dr. William J. Schmidt, II 
To: rldillon ; elecraft ; 
KX3 

Sent: Sun, Mar 9, 2014 8:49 pm
Subject: RE: [Elecraft] KXPA100 SN 707 Total Frustration with this Amp

Am I reading this correctly?  You are driving an AL80B with the KXPA100
being driven by the KX3?  That's quite imaginative if that's correct.  The
SWR fault is coming from the AL80B input circuit not your antenna (the KXPA
can't see the SWR on the other side of the AL80B).  probably something bad
in the input circuit of the AL80B causing the high SWR...


Dr. William J. Schmidt - K9HZ / J68HZ/ 8P6HK/ ZF2HZ
  
Owner - Operator

Big Signal Ranch
Staunton, Illinois
  
email:b...@wjschmidt.com  


__._,_.___
Reply via web post 
 
	Reply to sender 
 
	Reply to group 
 
	Start a New Topic 
 
	Messages in this topic 
 
(1)


Visit Your Group 
 



  * New Members


13

Yahoo! Groups 
 

. Privacy 
 . 
Unsubscribe 
 . Terms 
of Use 

.

__,_._,___


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Elecraft] KXPA100 remote DC Power Control

[John Marvin]

It looks like there may be multiple ways of controlling power on the 
KXPA100. Obviously there is the front panel power switch. Another method 
is that the KX3 can turn the amp on. Does anyone know how that is 
accomplished? It appears there is a "PWR ON" pin in the 8 pin control 
connector, but looking at the KX3 interface cable it doesn't look like 
anything is connected to it. Is there an undocumented serial command 
involved? I don't see anything in the command interface document, but 
perhaps I missed it.


Second, how does the "PWR ON" pin work, i.e. does a voltage have to be 
applied, or does the pin have to be connected to ground?


FYI, I don't own a KX3, but I'm wondering about the possibilities of 
controlling power to the KXPA100 remotely.


Thanks,

John
AC0ZG
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Advice on 6 meters...

[John Marvin]

Rick,

Be careful who you call ignorant. HDTV is NOT UHF only. After the 
digital transition most stations went to UHF. However, there are still a 
lot  digital stations in the high VHF range (channels 7-13). I can 
receive 4 high VHF stations in my area (Fort Collins, north of Denver 
CO).  There are also still a handful of digital TV (full power) stations 
in the US in the low VHF range (channels 2-6). On Channel 2 there are 8 
left in the US (nearest to me is KREX-TV in Grand Junction, CO) and 2 in 
Canada.


There are also more low power TV (LPTV) stations on Channel 2 (on the 
order of 50 in the US). Since LPTV stations haven't been required to 
transition to digital yet there is a mix of analog and digital LPTV 
stations.


So, if anyone asks, tell them you are trying to get DX reception of 
KSNV-DT in Las Vegas (nearest full power RF channel 2 to you) or KFTY-LD 
in Santa Rosa, CA (nearest low power digital TV station to you).


John
AC0ZG


On 2/26/2014 1:43 PM, Rick WA6NHC wrote:

I live in an HOA infested area, my mistake.

Six meters is a LOT of fun now that the concerns over channel two 
interference are gone.  When it is open, it's 'magic' to the point 
that almost anything works well.


I intend to put up a 'TV' beam antenna (not allowed by the HOA but 
others are around so that practice is ignored).  At least to the 
uninformed, it 'looks' like a TV antenna in size and shape.  I will 
take advantage of the common ignorance that HDTV is UHF, not VHF (need 
a smaller antenna now).  It will 'just happen' to resonate REALLY well 
on six meters.  ;o)  It's not my fault the HOA is ignorant and I don't 
intend to inform them of this matter. ;-)  The only real trick is that 
I don't own the roof or the outer 'skin' but since I'll be getting a 
new roof, I figure a case of beer or a bottle of Scotch to the actual 
roofer will be helpful in making connections to the roof.  I'll have 
them install a weatherhead for feedline, then have THEM attach the 
anchor to the roof and supporting mast (it will already be >40' above 
dirt, can't be taller because of a nearby airport).  Then I'll um, 
simply take advantage of what they left behind (and do the install 
when folks are at school/work).  I may even try it on a TV.  ;o)


In the meantime, I made a J pole tuned for the upper end of the band 
(back deck, completely HOA legal).  I can work the club repeater and 
others, while listening for band openings (KRX3).  It isn't ideal (too 
many of my computers, too close to the house), but I'm still building 
the station up while keeping most of it stealth.  Six meters has 
better coverage in hilly country than two meters, so wide area 
coverage is pretty easy here (Sierra foothills).  [The club repeaters 
are 6M-900Mhz with interties possible so we saturate our target area.]


So yes, a beam would be an excellent idea.  The cost for building a J 
pole varies with the cost of copper (don't use thin wall and don't use 
half inch on the lower halves, it flops too much, ask me how I know).


73,
Rick wa6nhc


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] PA with predistortion

[John Marvin]

I'm not sure how easy this would be to adapt to an existing product like 
the K3 or KX3. Note that the primary change is in the transceiver and 
not the PA, i.e. this is not something you would add to the KXPA100 or 
KPA-500, other than perhaps the head end of the PA output sampler. The 
attenuator part of the sampler could also go in the PA or that could go 
in the feedback input that would have to be added to the transceiver. In 
a self contained transceiver (i.e. with a built in PA) this could all be 
contained within the transceiver, although it would still be nice to 
provide an external feedback path for those with additional 
amplification (e.g. a KPA-500). This is what Apache-Labs is doing with 
the not yet released ANAN-200D. Earlier HPSDR based products based on 
the Hermes board or Angelia board are also capable of supporting 
predistortion, but it requires some changes, along with an external RF 
sampler of some type (although some people are getting decent results 
from just the crosstalk in the ANAN-100D case, although some of the 
settings need to be calibrated on a per band basis since the crosstalk 
level tends to change with frequency).


In order to do this you need to add a feedback path in the transceiver 
and the transceiver needs to support full duplex operation, i.e. either 
the feedback path needs to connect to an additional receiver or the T/R 
circuit needs to connect the feedback path to the receiver while the 
transmitter is connected to the PA/antenna. The DSP then needs to be 
able to monitor both the outgoing transmit signal and the incoming 
properly attenuated signal from the PA output. This can all be built 
into the transceiver for the "barefoot" case (I'm not sure barefoot 
applies in the case of a K3/100!). Of course the DSP needs to be capable 
of computing the required predistortion based on the feedback input, 
accounting for delay in the transmit path, and applying it to the 
transmitted signal.


I will also note that the results are best with higher voltage PA 
designs, e.g. LDMOS 50V amps. But the results can still be quite good 
for well designed 13.8v amps. I'm working on getting this to work with 
my HPSDR Hermes and my KXPA100, although it is a low priority task right 
now. I need to verify that the feedback signal from the KXPA100 is 
reasonably stronger than crosstalk within the transceiver, which 
contains a Hermes board and the 5W driver amp from the Hardrock 50 kit, 
and yet it can't be so strong that it overloads the ADC.


When it comes to IM3 distortion, applying correction from earlier in the 
transmit path can still result in some improvement, i.e. the distortion 
from earlier stages just gets amplified and added to new distortion 
products at each stage. When I looked at the KXPA100 test results that 
Elecraft submitted to the FCC, I noticed that the input test signal 
wasn't all that great. I wondered how much of the IM3 product at the 
KXPA100 output was contributed by the KXPA100 and how much was just the 
IM3 distortion from the input amplified by the KXPA100.


Regards,

John
AC0ZG

On 2/25/2014 10:31 AM, Sverre Holm (LA3ZA) wrote:

"Apache Labs become the first Amateur Transceiver manufacturer to include
Pre-distortion technology within their PA’s for ultra-clean TX".

This is something that Elecraft should have all the possibilities to follow
up on: using the DSP to clean up the PA.

See  http://blog.wsplc.com/?p=1701 




-
Sverre, LA3ZA

K2 #2198, K3 #3391,
LA3ZA Blog: http://la3za.blogspot.com,
LA3ZA Unofficial Guide to K2 modifications: 
http://la3za.blogspot.com/p/la3za-unofficial-guide-to-elecraft-k2.html
--
View this message in context: 
http://elecraft.365791.n2.nabble.com/PA-with-predistortion-tp7584706.html
Sent from the Elecraft mailing list archive at Nabble.com.
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Would anyone like to see an all-mode VHF/UHFoffering from Elecraft?

[John Marvin]

One issue with the XV transverter option is that they only cover part of 
each of the bands, dropping the regions primarily used for FM repeater 
and FM simplex use. Even if someone wants the transverter primarily for 
non FM modes, they still might want to be able to also use the rig for 
FM repeater base station operations. Even the KX3 2m module recognizes 
this by providing coverage for the entire 2m band, plus extended range 
at reduced sensitivity, whereas the XV144 only covers the lower half of 
the band.


John
AC0ZG

On 1/31/2014 7:08 AM, Joe Subich, W4TV wrote:


No, it already exists in the K3/10 with XV-144/220/432 or the
K3/10 with KXV-144 for those wanting only 6 and 2.

Better if Elecraft were to spend their development time on with
simultaneous crossband receive and reverse VFO tracking with the
K3/KRX3 for satellite operation and working on a larger, true
home station, 200W K4.

73,

   ... Joe, W4TV




__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] W2 wattmeter not reading xv50 output

[John Marvin]

I'm not sure I can explain this. But it's possible the problem is a 
combination of two possible error sources:


1) I believe the XV50 leds are displaying power based on the voltage at 
the final stage, and is not using a SWR bridge to measure forward power. 
The W2 is measuring forward power, so if the SWR is greater not 1:1 then 
it will measure a lower value than what the XV50 is displaying. Did you 
take note of SWR and reverse power using the W2 utility? Since you are 
driving another amp I wouldn't expect a really high SWR though.


2) Did you build your XV50 or did you get a factory built version? If 
factory built then Elecraft would have properly calibrated it. If you 
built it, did you perform all the calibration steps? Since you already 
mentioned you don't have a lot of test equipment, you may not have been 
able to calibrate the XV50 properly. In particular, if calibrated 
properly, 1mW drive should produce 20 watts output, not 30.  Also,  you 
should try to avoid sending more than 1mW to the XV50.


Final question. How were you generating the test signal and what mode 
were you using?


John
AC0ZG

On 1/23/2014 8:10 AM, Bob KD7YZ wrote:

On 1/22/2014 02:05, John Marvin wrote:

Bob,

You should try installing the W2 utility

Just went and D/L. Thanks .

XV-50 into a dummy-load:
K3-DriveW2-UTil XV50 BarsW2-Box-LED

0.1mW drive 0.50W on W2 2 bars ((2W) 0
0.2mW drive 0.83W on W2 4 bars ( 5W  0
0.3mW drive 1.42W on W2 5 bars   7W  1 1watt
0.4mW drive 1.90W on W2 6 bars  10W  1 1watt
0.5mW drive 2.41W on W2 6 bars  10W  2 2watt

0.6mW drive 3.02W on W2 7 bars  15W  3 3watt
0.7mW drive 3.66W on W2 8 bars  20W  3 3watt
0.8mW drive 4.23W on W2 9 bars  25W  4 4watt
0.9mW drive 4.81W on W2 10bars  30W  4 4watt

1.0mW drive 5.35W on W2 10bars  30W  5 5watt
1.5mW drive 8.80W on W2 10bars  30W  8 8watt

So, as you see, nothing agrees with anything. Note: I am not a test-lab
and have little in the way of measurement equipment. Coaxial-Dynamics in
the PA output. However, 500/1000 watt slugs.

But, the XV50 drives the 180w 6m brick to an acceptable low limit (based
on XV50 drive).
The Brick drives the PA to 1250W .. so I can't complain in that regard.
Just wanted to monitor/see the output of the XV50 and can't seem to do it.



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] W2 wattmeter not reading xv50 output

[John Marvin]

Bob,

You should try installing the W2 utility (obviously you need to connect 
your W2 to a computer via the USB/serial cable that came with the W2 in 
order to do this). It shows the SWR and forward power with more 
precision than you get with the led front panel display. It would be 
interesting to see if you see a different reading when transmitting with 
the XV50 vs.  when you are not transmitting, even if the value is very 
low (i.e. low enough not to light a single led).


Which range led is lit on the front panel?

John
AC0ZG

On 1/21/2014 9:39 PM, Bob KD7YZ wrote:

It's the correct sensor. The W2 reads the K3 output. But when it's
cabled to the Elecraft 6m Transverter, there is no power reading. I
sometimes see a few green LED's for 1.3 to 1.5 VSWR. Never a power reading.



__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Requirements for keying a KXPA100

[John Marvin]

I got a variety of suggestions, and decided to go the easiest route 
(since it worked) of removing the current limiting resistor and 
switching the diode to a schottky diode. The extra diode is required in 
my case because the PTT also keys an internal TX preamp whose keying 
circuit is run on 13.8V. Without the diode this circuit (unless I chose 
another suggestion of creating two separate PTT drivers on the 
transceiver) would see the floating 5V in the KXPA100 as a "relative" 
ground, so just connecting the KXPA100 key line would have caused the 
internal TX preamp to be keyed.


It was clear that a current limiting resistor was not required for 
either the internal TX keying circuit or the KXPA100 (they key current 
is about 1 mA for each of them). I decided if a current limiting 
resistor is required for keying another amp I can build an external 
adapter cable that includes the resistor for that use case.


With the schottky diode in place the Hermes transceiver pulls the 
KXPA100 key line down to about 0.39 volts, which should be enough to 
trigger it with hopefully a comfortable margin. Everything appears to be 
working properly now, so now I get to play!


Anyway, thanks to all for the helpful suggestions.

73,

John
AC0ZG
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Requirements for keying a KXPA100

[John Marvin]

Oops, sorry for the prior mistaken posting.

I just realized I can try an experiment directly shorting the key input 
of the KXPA100 through a variable resistor, in order to find what is 
required to trigger it. I can then do the math and add another .1v 
safety margin in order to determine whether I can go with a simple 
change or something a little more involved.


John
AC0ZG

On 1/14/2014 2:08 PM, John Marvin wrote:

Lyle,

Thanks. I would have thought that a transistor driver would have been 
used to drive the I/O pin. Anyway, I measured the voltage drop across 
the key input of the KXPA100 when the transceiver was attempting to 
key the amp. The drop was 2.1 volts. Since the voltage for the circuit 
is internal to the KXPA100, this is the voltage drop within my 
transceiver (i.e. the switching diode, the 560 ohm current limiting 
resistor and the keying circuit on the Hermes board), leaving 2.9 
volts for the KXPA100. I don't know what else is in the circuit inside 
the KXPA100, so I don't know if the microprocessor is seeing that 
entire 2.9v. Do you know whether or not that is the case?


I could get another .3 volts or so by switching to a schottky diode, 
and possibly another .15 volts if I cut the resistor value in half 
(I'd like to guarantee a maximum current of about 50ma (when keying a 
12-13.8V circuit), since the Hermes keying circuit is rated for up to 
100ma). That would give about 3.35 volts, which still is under the 
3.5v normally required to trigger a high state for cmos. That might 
work, but I'm not sure I want to live with something that might be flaky.


I want to preserve the capability of triggering an amp with a relay 
coil in the keying circuit, so I don't want to drop the diode. I fried 
the tiny IC switch on the Hermes board once, and although I'm 
reasonably competent when it comes to surface mount soldering, I don't 
relish doing that repair again. I haven't had another failure (not 
entirely sure of the cause of the first failure) since adding the 
additional protection in the circuit (the diode, resistor and a bypass 
capacitor). I may have to consider a different design where the Hermes 
keys a transistor switch which then provides the path to ground for 
the tx preamp and the external amp. That way the transistor can be my 
"fuse" and I can then reduce the circuit elements in the keying path.


John
AC0ZG


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Requirements for keying a KXPA100

[John Marvin]

On 1/14/2014 2:08 PM, John Marvin wrote:

Lyle,

Thanks. I would have thought that a transistor driver would have been 
used to drive the I/O pin. Anyway, I measured the voltage drop across 
the key input of the KXPA100 when the transceiver was attempting to 
key the amp. The drop was 2.1 volts. Since the voltage for the circuit 
is internal to the KXPA100, this is the voltage drop within my 
transceiver (i.e. the switching diode, the 560 ohm current limiting 
resistor and the keying circuit on the Hermes board), leaving 2.9 
volts for the KXPA100. I don't know what else is in the circuit inside 
the KXPA100, so I don't know if the microprocessor is seeing that 
entire 2.9v. Do you know whether or not that is the case?


I could get another .3 volts or so by switching to a schottky diode, 
and possibly another .15 volts if I cut the resistor value in half 
(I'd like to guarantee a maximum current of about 50ma (when keying a 
12-13.8V circuit), since the Hermes keying circuit is rated for up to 
100ma). That would give about 3.35 volts, which still is under the 
3.5v normally required to trigger a high state for cmos. That might 
work, but I'm not sure I want to live with something that might be flaky.


I want to preserve the capability of triggering an amp with a relay 
coil in the keying circuit, so I don't want to drop the diode. I fried 
the tiny IC switch on the Hermes board once, and although I'm 
reasonably competent when it comes to surface mount soldering, I don't 
relish doing that repair again. I haven't had another failure (not 
entirely sure of the cause of the first failure) since adding the 
additional protection in the circuit (the diode, resistor and a bypass 
capacitor). I may have to consider a different design where the Hermes 
keys a transistor switch which then provides the path to ground for 
the tx preamp and the external amp. That way the transistor can be my 
"fuse" and I can then reduce the circuit elements in the keying path.


John
AC0ZG

On 1/14/2014 5:28 AM, Lyle Johnson wrote:

John,

The diode drop is likely the primary culprit.  If you must use a 
series diode, use a Shottky diode (like a 1N5711) and not a silicon 
diode (like a 1N4148).


The key input goes to a microprocessor digital I/O pin inside the 
KXPA100, and a diode drop - especially with a significant series 
resistance -- puts the detected voltage in the indeterminate region.


73,

Lyle KK7P

So, I got my KXPA100 kit and have assembled it. But I'm having 
trouble keying it with my transceiver ...There is a 560 ohm resistor 
in series internally, along with  diodes...






__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] Requirements for keying a KXPA100

[John Marvin]

Lyle,

Thanks. I would have thought that a transistor driver would have been 
used to drive the I/O pin. Anyway, I measured the voltage drop across 
the key input of the KXPA100 when the transceiver was attempting to key 
the amp. The drop was 2.1 volts. Since the voltage for the circuit is 
internal to the KXPA100, this is the voltage drop within my transceiver 
(i.e. the switching diode, the 560 ohm current limiting resistor and the 
keying circuit on the Hermes board), leaving 2.9 volts for the KXPA100. 
I don't know what else is in the circuit inside the KXPA100, so I don't 
know if the microprocessor is seeing that entire 2.9v. Do you know 
whether or not that is the case?


I could get another .3 volts or so by switching to a schottky diode, and 
possibly another .15 volts if I cut the resistor value in half (I'd like 
to guarantee a maximum current of about 50ma (when keying a 12-13.8V 
circuit), since the Hermes keying circuit is rated for up to 100ma). 
That would give about 3.35 volts, which still is under the 3.5v normally 
required to trigger a high state for cmos. That might work, but I'm not 
sure I want to live with something that might be flaky.


I want to preserve the capability of triggering an amp with a relay coil 
in the keying circuit, so I don't want to drop the diode. I fried the 
tiny IC switch on the Hermes board once, and although I'm reasonably 
competent when it comes to surface mount soldering, I don't relish doing 
that repair again. I haven't had another failure (not entirely sure of 
the cause of the first failure) since adding the additional protection 
in the circuit (the diode, resistor and a bypass capacitor). I may have 
to consider a different design where the Hermes keys a transistor switch 
which then provides the path to ground for the tx preamp and the 
external amp. That way the transistor can be my "fuse" and I can then 
reduce the circuit elements in the keying path.


John
AC0ZG

On 1/14/2014 5:28 AM, Lyle Johnson wrote:

John,

The diode drop is likely the primary culprit.  If you must use a 
series diode, use a Shottky diode (like a 1N5711) and not a silicon 
diode (like a 1N4148).


The key input goes to a microprocessor digital I/O pin inside the 
KXPA100, and a diode drop - especially with a significant series 
resistance -- puts the detected voltage in the indeterminate region.


73,

Lyle KK7P

So, I got my KXPA100 kit and have assembled it. But I'm having 
trouble keying it with my transceiver ...There is a 560 ohm resistor 
in series internally, along with  diodes...




__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Elecraft] Requirements for keying a KXPA100

[John Marvin]

So, I got my KXPA100 kit and have assembled it. But I'm having trouble 
keying it with my transceiver (HPSDR Hermes with alterations to support 
driving the KXPA100). My circuit didn't have any trouble keying my 
previous amp (a HFPacker V4). If I manually short the KXPA100 key input 
things appear to work in the limited testing I've done, so I don't think 
there is anything wrong with the KXPA100.


I've measured 5V as expected at the key input, and I've measured the 
current while connecting the KXPA100 key input to my transceiver. I'm 
measuring 0.58 mA when the transceiver attempts to key the amp. The 
KXPA100 manual says that the key current will be 1 mA max (if I am 
reading that correctly) so this seems to be about right. Is there a 
minimum current requirement? There is a 560 ohm resistor in series 
internally, along with  diodes (one in line with the key output to the 
KXPA 100 and one inline with the key output to the internal tx preamp) 
to prevent interaction between the two.


Any ideas? My next experiment will probably involve changing or 
bypassing the 560 ohm resistor, but I have doubts that will fix the problem.


John
AC0ZG
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] OT - anyone have experience with effects of metal roofs on antenna performace?

[John Marvin]

Sorry, that was not my intention. We all do "stupid" things. The 
intention of my post was not to say that what you did was stupid. My 
illustration particularly mentioned running high power, which you 
already said you had not done, as an extreme to illustrate the point.  
Insurance won't cover it if it is proved to be an intentional act, and 
even intentional acts are covered for kids up to a certain age.


The intention was to clear up the misconception that if one of our homes 
was damaged or destroyed by doing something that in hindsight might not 
have been the wisest thing, insurance still would cover it. But I can 
see that this discussion could turn off into a long discussion that has 
nothing to do with Elecraft or ham radio, so it should probably die 
right here.


73,

John
AC0ZG

On 7/4/2013 2:54 PM, Jim Bennett wrote:

Not sure I'm liking where this conversation is going. I answered the original poster's 
question as to whether a metal roof has been seen to adversely affect antenna 
performance, not advocate doing "stupid" things. My installation worked very 
well for me w/o running high power. I knew I WOULD be doing QRO after a new roof was 
installed and subsequently ran my feeder in an appropriate location.

Jim / W6JHB

On   Thursday, Jul 4, 2013, at  Thursday, 12:52 PM, John Marvin wrote:


I didn't see the original reply, but I just wanted to clear up one 
misconception. Homeowner's insurance covers stupidity. Unless it can be proved 
that you put that ladder line on the roof and ran high power through it with 
the intention of burning the house down, you would be covered.

73,
John
AC0ZG

On 7/4/2013 1:19 PM, Jim Bennett wrote:

Yes. Yes I was. :-)

On   Thursday, Jul 4, 2013, at  Thursday, 12:11 PM, Tom H Childers wrote:


You must have been running very low power.  Laying any kind of
ladder-line on a roof, insulated or not, is an excellent way to have
a house fire that the insurance company will not pay for. Especialy a
shake shingle roof.

73,
Tom
Amateur Radio Operator N5GE
ARRL Lifetime Member
QCWA Lifetime Member

[snip]
73,
Tom
Amateur Radio Operator N5GE
ARRL Lifetime Member
QCWA Lifetime Member


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] OT - anyone have experience with effects of metal roofs on antenna performace?

[John Marvin]

I didn't see the original reply, but I just wanted to clear up one 
misconception. Homeowner's insurance covers stupidity. Unless it can be 
proved that you put that ladder line on the roof and ran high power 
through it with the intention of burning the house down, you would be 
covered.


73,
John
AC0ZG

On 7/4/2013 1:19 PM, Jim Bennett wrote:

Yes. Yes I was. :-)

On   Thursday, Jul 4, 2013, at  Thursday, 12:11 PM, Tom H Childers wrote:


You must have been running very low power.  Laying any kind of
ladder-line on a roof, insulated or not, is an excellent way to have
a house fire that the insurance company will not pay for. Especialy a
shake shingle roof.

73,
Tom
Amateur Radio Operator N5GE
ARRL Lifetime Member
QCWA Lifetime Member

[snip]
73,
Tom
Amateur Radio Operator N5GE
ARRL Lifetime Member
QCWA Lifetime Member


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Re: [Elecraft] KX3 Amp

[John Marvin]

One correction. The HF Packer is not a 50w amp. It's about 45w at 160m, 
and then steadily less as you go up in frequency (40w for 80m, 35w for 
40-20m, 30w for 17/15m, 25w for 12m and about 20w for 10m). It doesn't 
support 6m. These numbers come directly from a graph in the HF Packer 
manual.


John
AC0ZG

On 6/30/2013 10:18 PM, Ariel Jacala wrote:
Hands down the KXPA100.  It isn't out yet - shipping in August but offers the greatest flexibility with a tuner and portability.  The Hardrock is ~$260.  It is only available to members of the Yahoo group right now.  It is 160-6m and generates a solid 50w from 160-10, less on 6m.  I own a Hardrock and it was a difficult build but Jim Veatch helped me out a lot - WA2EUJ.  No tuner though so you will have to invest in a ZL100 or equivalent.  The Elecraft tuner is  faster and tunes a wider range.  Size wise is only slightly smaller than the Elecraft 4 1/8 wide and tall by 7 deep.  The TenTec is a larger amp - $800 plus a 100w tuner.   The THP HL45B is a solid performer at about $450 from HRO.  Again you need an outboard tuner.  You have to manually switch bands.  If you don't it will go on standby - a self protective feature.  I played with a THP for a while and it works well.  You can get one used - not easy - for about $250-$300.  There are the RM Italy variants - beware do 

no

  t overdrive - IMD artifacts - HL300B is the model - only drive to 100W - I 
have no experience with this amp. These are not certified by the FCC.   Some 
people have had great luck with the Juma 100w amp and some on the reflector may 
have owned one or built one.  The Jumas can be programmed to band switch with 
the rig.  Again - it needs an external 100w tuner.

So here are your choices:

Juma 100w - no tuner - band switches with rig automatic - FCC certified
Hardrock 50w - no tuner - manual switching - not FCC certified
TenTec - 100w - no tuner - band switching with rig automatic
HFPacker - 50w - manual swiching
KXPA100 - 100w - tuner - automatic band switching - FCC certified
THP HL45B - 45w - no tuner - manual switching (except for FT817) - FCC certified
THP HL100B - 10w - no tuner - manual switching - not FCC certified
RM Italy HL150 - 150w - no tuner - manual switching? not FCC certified
RM Italy HL300B = 300w - no tuner - manual switching? not FCC cerified

Antennas
Too many to list
Personal favorites - G0GSF- multiband dipole - 4 bands are OK w/o a tuner, EFHW 
- cut to 45 ft with EARCI matchbox KX3 tuner will match 80-10m
  
Ariel NY4G

Sent from my iPad

On Jun 30, 2013, at 11:39 PM, "KF5TEU"  wrote:


While all these posts have good advice for a bc trip , I really just want the 
KX3 amplifier. I have the other items already ( Delorme GPS plus SPOT with 
rescue insurance paid up, sat. phone rented , several 2M HT's ( APRS godd idea 
, I'll add that ) and the usual flares , panels , noisemakers and things that 
go bang ) .


But...I need an amplifier and the right antennas to add to this.
We will be doing the check in via SPOT , sat. AND am. band.
SPOT loses lock in jungle and mountain ,vso do sat. phones and GPS.
Certain unfriendlies like to jam their freq's as well.
In addition to that any or all that gear can be broken , lost or confiscated by 
certain sticky fingered locals ( it.s happened ).
Hard to jam 6M-160M all the time though.
I am not "shouting in the dark" for rescue.  We have several pre-planned 
operators standing by with preplanned times and frequencies and backup frequencies.
But, they are also mobile or may have interference so I want the best chance at 
a clear signal both ways.
There are no repeaters out there.
This is in Africa.

Please , any KX3 amplifier advice ?
Ten-Tec , Hardrock , etc. , which specific models with setup/operating tips ?
Greatly appreciated !

Bill"ny4g [via Elecraft]"  wrote:Some 
HT's have GPS and with APRS one can send messages.  I have used it on hikes so my wife can 
track me on the internet as I hike.  The HT sends a beacon signal out and the movement can be 
tracked through APRS.fi   Any Ham can get an APRS account.I have even used APRS on my 
iPhone for the same tracking capability.  Remote from civilization though you would need an HT 
with APRS like the VX8R by Yaesu or a TinyTrack tracker.  With the HT however, you can call for 
help and the reach can be substantial depending on elevation or having a nearby repeater.  
Having worked 45 states on Field Day just using a KX3 and a G0GSF dipole, I have no qualms with 
getting out and reaching people with a KX3 on HF.  When the 2m module gets out - I have a 
complete package for all modes of remote operation.
Ariel NY4G


From: [hidden email]
To: [hidden email]
Date: Sun, 30 Jun 2013 19:51:08 -0400
Subject: Re: [Elecraft] KX3 Amp

That's what I'd do as well.  Some personal locators will send an "I'm
OK" message, too to designated recipients.  And, if you don't want to
buy a personal locator... you can rent them, which might be less
expensive, if it's a one-time trip.

73 de 

Re: [Elecraft] W2 wattmeter

[John Marvin]

As you mentioned, the W2 utility shows greater accuracy, although just 
because it shows values in fractions of a watt, it doesn't mean that it 
is that accurate. However, the nice thing about the W2 is that it has a 
fairly nice calibration facility. So if you have or can borrow a higher 
accuracy meter then you can use that to improve the accuracy of the W2.


Also, I really like the fact that the SWR bridge sensor is remote from 
the unit. This allows a lot more flexibility for setup. In my case the 
cable was just a little too short, but I wondered if a CAT 5e patch 
cable would work. I did a little googling and saw an Elecraft employee 
recommending that option. I don't know how long you can go before it 
doesn't work or gives bad readings, but the patch cable I used was only 
2-3 feet longer than the cable supplied by Elecraft, and it didn't 
appear to affect the readings based on a simple before/after test.


Anyway, I think the W2 is a great product.  However, Elecraft recommends 
that it go between the amp and the ATU (Elecraft says that the accuracy 
really starts to suffer with high SWR). That means that it might not be 
very useful if I purchase a KXPA100 with the built in ATU.


John
AC0ZG

On 6/15/2013 9:34 AM, Donald Butler wrote:

I have two W2 meters and I like them  .. But I do not rely upon them for
accurate power readings.. My more practical use is to use my peripheral
vision to keep tabs on what's going on while I'm on the air and be alert for
unexpected changes.

I think the Bird 43, when fully calibrated, claims plus or minus 5% accuracy
at full scale on their analog dial.

The W2 is probably close to that, but not quite (maybe 6% at best) ... there
are 17 leds on the 0-20 watt meter scale  .. Doing the math, on the 2KW
scale, that's about 118 watts per LED ... so the power has to increase about
118 watts before the next LED will light up, etc., etc.Yes, you can get
a reading of presumed accuracy to the nearest watt if you us the W2 software
and keep a window running on your computer  . but the LED display itself is
only capable of reading plus or minus 118 of actual wattage on the 2 KW
scale.. And I've never bothered to calibrate to see what it takes for the
next LED to light up .. Does it change when you (1) just cross the new
threshold, (2) hit the midrange area of the next step, or (3) go the full
distance.Bottom line, it really doesn't matter, but I do not use a W2 to
obtain accurate power readings just from the LED display.

Don, N5LZ

-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Fred Smith
Sent: Saturday, June 15, 2013 8:28 AM
To: 'NZ0T'; elecraft@mailman.qth.net
Subject: Re: [Elecraft] W2 wattmeter

Bill is 100% right on about the W2,it is most useful on screen for extreme
QRP if you don't have a WM-2 QRP meter. But like I said earlier it is very
close for all ranges both of my couplers are 2k's but still not bad for QRP.


73,
Fred/N0AZZ
K3 Ser #'s 6730/5299--KX3 # 2573--K2/100 # 6470-KAT100
P3/SVGA--KPA500--KAT500--W2



-Original Message-
From: elecraft-boun...@mailman.qth.net
[mailto:elecraft-boun...@mailman.qth.net] On Behalf Of NZ0T
Sent: Saturday, June 15, 2013 7:16 AM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] W2 wattmeter

Very happy with my W2.  I have the 2KW coupler.  Seems pretty accurate and
the LED display is great for casual use.  I don't always keep the display up
on the computer but it's very useful when greater resolution than the LED
display is desired.

73 Bill NZ0T



--
View this message in context:
http://elecraft.365791.n2.nabble.com/W2-wattmeter-tp7575272p7575286.html
Sent from the Elecraft mailing list archive at Nabble.com.
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
-
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2013.0.2904 / Virus Database: 3199/6413 - Release Date: 06/15/13

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/lis