Re: [Elecraft] (OT) - Unplanned Discovery

[Josh]

Noise can absolutely change with load. At light load the SMPS may enter a pulse 
skipping mode. Some keep pulse width constant and vary switching frequency with 
load to effectively change duty cycle. Most (all?) will continuously modulate 
the switching frequency over a small range to spread out the pulse energy. This 
makes it much easier to come in under required limits, but also by the time 
you're looking at harmonics up in our bands it's a big smudge of noise. 

73,
Josh W6XU

Sent from my mobile device

> On Nov 20, 2017, at 12:58 PM, Doug Smith  wrote:
> 
> I have often wondered if the noise from a switching power supply would vary 
> in intensity or other characteristics as the load changes.  For example, 
> during transmitting.  In a single transmitter environment the user would 
> probably not notice but in a multi-transmitter or SO2R station one just 
> might.  
> 
> Changes in noise floor might not always be “phase noise” from the other 
> transmitter — could it be different emissions from a switching power supply 
> under full load?
> 
> 73,
> Doug, W7KF
> http://www.w7kf.com 
> 
> 
>> On Nov 19, 2017, at 6:42 PM, stan levandowski  wrote:
>> 
>> Yeah, me too.  I bought it because I thought it would be "super clean" and 
>> really small.  But its contribution to my problem was pretty much 
>> unarguable:  Plug it in and I hear noise.  Unplug it and I don't hear noise. 
>>  The instructions that came with it specifically stated that the Kx33 should 
>> be placed the full length of the DC plug/cord away from the transceiver.  I 
>> did that but it didn't work for me.  I tried different outlets around the 
>> house too.  I put chokes on it.  No joy.
>> 

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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Kevin Cozens]

On 2017-11-19 04:24 AM, Richard Lamont wrote:

The people being trained by the US Navy to read Morse are intercept
operators.


The article indicated that they are only learning morse for a standard latin 
(ie. English) alphabet. A number of years ago I visited the radio room while 
on a boat cruise in the Caribbean. The radio operator was copying down morse 
coming in over the radio. I tried to see what I could copy in my head but I 
couldn't make sense of it. When I looked at what the radio operator was 
writing down it was Greek. I don't mean as in "it was Greek to me" but that 
it was actually in the Greek language. The US Navy morse interceptors will 
need to be able to copy morse in multiple languages to be truly effective.


--
Cheers!

Kevin.

http://www.ve3syb.ca/   |"Nerds make the shiny things that distract
Owner of Elecraft K2 #2172  | the mouth-breathers, and that's why we're
| powerful!"
#include  | --Chris Hardwick
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Re: [Elecraft] (OT) - Unplanned Discovery

[Edward R Cole]

Up here in Alaska its not unusual to experience loss of commercial 
power (often due to Inclement wx or avalanche).  I've noted how quiet 
my radio is when no one around us has power.  Even running our 6500w 
Honda invertor-generator its very quiet (which also tells my noise is 
coming from neighbors and not my appliances).


Also, I have found the IBM Think pad (laptop) is very quiet (even 
with charger).  I think this largely because the case is metallic and 
not plastic.


This story does remind us to periodically check our house for noise 
sources - might be pleasantly surprised.


I have been plagued by S9 level interfering noise on 144-MHz for 3-4 
years.  Recently I checked coax loss on some lines when I had to roll 
up all for some house work.  I found excessive loss in my two 
130-foot LMR-400 Rx lines (runs from preamps on tower to transverter 
in house).  Since replacing the lines I think I have lessened the 
interference, making suspect some may have been due to passive 
intermod in those lines.  Loss was probably moisture caused corrosion 
which might interact with out of band signals.  Passive IM is tested 
by the cellular industry at their tower sites.


I still see occasional noise interference but its less often and less 
problem-some.


73, Ed - KL7UW
  http://www.kl7uw.com
Dubus-NA Business mail:
  dubus...@gmail.com 


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[Elecraft] (OT) - Unplanned Discovery

[Howard Hoyt]

Hi Stan,

One thing we have learned in supplying thousands of Kx33s to hams is the 
importance of minimizing or eliminating common-mode currents in the 
antenna system.  The transverse mode RFI output of the Kx33 is extremely 
low and has never been the cause of noise to our customers, but if the 
antenna system has significant common-mode potential, it will always 
seek a current path through whatever is attached to the rig...through 
the power supply, your body, as well as grounds.  The outside of the 
coax shield, the rig, the power supply and AC mains are all in a series 
path for common-mode currents.


The most direct cure is to place a high common-mode impedance in the 
antenna feedline.  The DC power lead on the Kx33 is smaller in diameter 
than most RF coax lines, so it may be easier to form a choke on that 
cable.  You mentioned "YES, I HAD CHOKES ON ALL SUPPLIES, CABLES, 
WIRE."  The exact core material used and number of turns is important in 
constructing common-mode chokes.  Jim Brown, K9YC has excellent 
tutorials on this subject: http://audiosystemsgroup.com/RFI-Ham.pdf


Another measure which will shunt common mode currents away from other 
paths is a low impedance ground on the rig.


Something else I want to mention, as it is an issue which has cropped up 
recently: There are several sellers on both eBay and Amazon stating "Pro 
Audio Engineering  Kx33 power supply" in their ads, but no supplies 
other than those sold directly from us are the actual Kx33.  We know 
this because we worked with one such customer to resolve noise issues 
and it turned out the unit he had was not a Kx33.  eBay and Amazon both 
state they can not do anything, since the other vendors are claiming 
they use our part number and name only to state an equivalency, which 
they most assuredly are not.  Our Kx33 has less than 70 pF of input to 
output coupling vs. 1000 pF or more for most other supplies, making it 
far easier to choke common-mode currents.  This was the most difficult 
spec of the supply to arrive at, but considering we knew it could be 
used with temporary antenna systems with common-mode potential it was 
important to achieve.


As we unconditionally guarantee everything we sell, please contact us at 
i...@proaudioeng.com and I am sure we can help you eliminate this noise 
or refund your purchase price.


Cheers & 73,

Howard Hoyt - WA4PSC
www.proaudioeng.com

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

Hi Frank,

 

Thanks for your very useful comments. Below my answers:

 

>Radiation results from RF current flowing in an antenna.  An RF

>ammeter is a useful instrument for measuring the relative efficiency

>different types of matching networks feeding similar antennas.

Granted. I might want to add that to my plans. I know that the WSPRLite 
tolerates no more than 100 mW of reflected power, and to avoid accident risk I 
intend to set the transmit power to no more than 100 mW. I do not know how the 
units might fold back transmit power in a scenario where the SWR is good but 
less than perfect. For this reason I am planning to use a tuner whenever SWR is 
not very close to ideal. The location of the tuner would be wherever it would 
make sense to place it in field operation. If I add ammeters, they would be 
placed at the feedpoint, which should work well when I compare different 
impedance transformers using identical wires. If I compare to non-resonant 
wires or center feed, it would be hard to compare ammeter readings.

 

> 1.  The two antennas under test should be located within less than

>one wavelength of each other, otherwise independent selective fading

>becomes a significant source of measurement error.  

Interesting. You are saying that this applies even if the comparison is done 
over several hours?

In my limited back yard, and because I want the feedpoints close to each other, 
I will certainly meet the requirement of staying withing one wavelength.

 

>2;  Horizontally polarized antennas should be oriented end-to-end

>to each other to avoid significant parasitic interaction that washes

>out the other differences in antenna performance

My earlier comments about end-fed antennas focused on vertical wires since the 
thread originator had tall trees that suggest vertical orientation. My 
preferred 24” support poles used with 60+ ft wires lead me to the inverted vee 
configuration which will be horizontally polarized. I am surprised that you can 
avoid parasitic interaction if you place the wires end-to-end. I was under the 
impression that end-to-end vertical wires, as in an elevated vertical with a 
resonant length of vertical feedline under it, with a common mode choke 
preventing current going from the radiator to the coax shield, would still 
suffer from parasitic coupling unless an additional common mode choke is added 
somewhere along the feedline to break up the resonance. I am influenced here by 
a QST article about vhf/uhf verticals where it seemed that multiple common mode 
chokes were found necessary to prevent feedline radiation. Anyway, these 
situations should be easy to model, and I assume you have looked closely at it. 
I should have enough room to place my inverted vee’s end-to-end if you are sure 
that is the best way. 

 

>3,  Do not attempt to compare horizontally polarized antennas to

>vertically polarized antennas, independent selective fading

>becomes a significant source of measurement error that takes

>an extraordinary amount of data collection to overcome.

Comparison between horizontal and vertical configuration is not part of my 
present plans, but I have to admit previously comparing my R5 vertical to my 
horizontal HF beam. I ran it several hours in several sessions at different 
times.There were times of day where sometimes the vertical seemed to work 
better than the beam, although overall the beam looked much better. Do I 
understand you to say that this comparison was flawed because of insufficient 
time spent?

 

73,

Erik K7TV

 

>Enjoy!

 

>73

>Frank

>W3LPL

 

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Brian Hunt]

For several years I've been using a 33 ft wire and a pair of small 
tapped loading coils to get  an EFHW vertical resonant on 20m. 30m and 
40m.  It's fed with a link coupled tuned tank circuit consisting of a 
coil on a 1 inch powdered iron toroid and an air variable capacitor.  
The link consists of 1-6 switch selected turns which gives a wide range 
of impedance transformation.  Antenna is supported with a 33 ft MFJ 
fiberglass mast.  Easy to set up and tune.  I do have to haul the wire 
down to change the taps and retune for a band change.  Used with a K1 or 
KX2, the internal ATU is usually in bypass.


73,
Brian, K0DTJ
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Re: [Elecraft] (OT) - Unplanned Discovery

[Doug Smith]

I have often wondered if the noise from a switching power supply would vary in 
intensity or other characteristics as the load changes.  For example, during 
transmitting.  In a single transmitter environment the user would probably not 
notice but in a multi-transmitter or SO2R station one just might.  

Changes in noise floor might not always be “phase noise” from the other 
transmitter — could it be different emissions from a switching power supply 
under full load?

73,
Doug, W7KF
http://www.w7kf.com 


> On Nov 19, 2017, at 6:42 PM, stan levandowski  wrote:
> 
> Yeah, me too.  I bought it because I thought it would be "super clean" and 
> really small.  But its contribution to my problem was pretty much unarguable: 
>  Plug it in and I hear noise.  Unplug it and I don't hear noise.  The 
> instructions that came with it specifically stated that the Kx33 should be 
> placed the full length of the DC plug/cord away from the transceiver.  I did 
> that but it didn't work for me.  I tried different outlets around the house 
> too.  I put chokes on it.  No joy.
> 

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Re: [Elecraft] (OT) - Unplanned Discovery

[Matthew Cook]

Josh,

You are quite correct.   The usual CISPR standards limits for many SMPS
designs are typically set to 50dBuV across the HF spectrum, that translates
to roughly 5/9+17dB.

These standards are there to protect your old analog TV and commercial FM
radio being messed up not your local Ham operator unfortunately.

73

Matthew
VK5ZM



On 20 November 2017 at 13:25, Josh  wrote:

> Most, if not all of those certifications are for safety, not emissions.
> Further, I'm not at all convinced that compliance with FCC/CISPR standards
> ensures no RFI to a ham station. Especially if your interests are weak
> signal, EME, etc.
>
> 73,
> Josh W6XU
>
> Sent from my mobile device
>
> > Just because it has the side or back posted with all types of
> certifications basically says  "they met specs at one time".
> >
>
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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Doug Smith]

Yes, it is morse code although the protocol is very different.  

For example, to call a distant (unknown) ship you point your big light at them 
and send AA.  The proper response is a lng T.  There’s a book carried 
aboard all ships that documents the protocols.  I have a copy here somewhere..

But it was NOT what you’d call high speed so Skip might have been referring to 
something else entirely.

And, yes, I have done ship to ship comms using signal lights.  It was in the 
Red Sea and Persian Gulf during Desert Storm.  Didn’t use them at all during 
OIF-I or OIF-II (2003, 2004).

(If interested further please contact me off-list.  I don’t want to prolong a 
marginally off-topic thread here..)

73,
Doug, W7KF
http://www.w7kf.com 


> On Nov 19, 2017, at 7:48 PM, dyarnes  wrote:
> 
> Fred and All,
> 
> I think Morse is exactly what they are using with the signal lamps.  The 
> article I read about this confirmed that.
> 
> Dave W7AQK

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[K9MA]

On 11/19/2017 02:22, Erik Basilier wrote:

The second approach, used by MyAntennas and others seems to use a
transformer with much higher impedance ratio. One way to construct such a
transformer would be to cascade two 9:1 units for an effective ratio of
81:1.


While I haven't tried it, it would probably be very hard to build a pair 
of 9:1 transformers or a single 81:1 transformer with low enough stray 
capacitance to work on the higher bands.  It might work up to 40 meters, 
I suppose.


The big advantage of a resonant end-fed half wave is that very little 
current flows in the ground system or counterpoise, so most of the power 
is going into the antenna.  While it is hard to match that high 
impedance with a non-resonant transformer, it is very easy to match with 
a simple L network.  The only reason the internal ATU in the KX3, etc., 
can't match it is that it doesn't have enough range.  (And for good 
reason.)  An external L network consisting of a tapped coil and variable 
capacitor will do it nicely.


73,

Scott K9MA

--
Scott  K9MA

k...@sdellington.us

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[Elecraft] KX3-2M SMA connector issue

[Mike Parkes]

I ordered the *KX3*-*2M for the KX3 and installed it yesterday, seems to be
working great. However... now I have an issue with the SMA connector coming
loose one me after only a few times placing the Elecraft 2m/440 whip
antenna on and off.*

*I was pretty careful to make sure the SMA antenna connector was mounted
securely. The instructions warned about overtightening. So I tightened it
down as much as seemed right. With lock washer compressed, I would have
thought it would be fine. Apparently not. *

*So now I have to break the thing back down to get to the antenna mount and
retighten. Anyone else have issues with this and how did you resolve? I
almost wonder if some locktite would help?*

*Thanks! Mike AB7RU*
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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[donovanf]

Hi Erik, 


Radiation results from RF current flowing in an antenna. An RF 
ammeter is a useful instrument for measuring the relative efficiency 
different types of matching networks feeding similar antennas. 


I'm well familiar with the simultaneous synchronized WSPRlite 
antenna performance analysis techniques, I developed the techniques 
that SOTAbeams implemented earlier this year! They work very, 
very well but a few things must be done to avoid significant 
measurement errors and biases: 


1. The two antennas under test should be located within less than 
one wavelength of each other, otherwise independent selective fading 
becomes a significant source of measurement error. 


2; Horizontally polarized antennas should be oriented end-to-end 
to each other to avoid significant parasitic interaction that washes 
out the other differences in antenna performance 


3, Do not attempt to compare horizontally polarized antennas to 
vertically polarized antennas, independent selective fading 
becomes a significant source of measurement error that takes 
an extraordinary amount of data collection to overcome. 


Enjoy! 


73 
Frank 
W3LPL 






- Original Message -

From: "Erik Basilier"  
To: donov...@starpower.net, elecraft@mailman.qth.net 
Sent: Monday, November 20, 2017 1:51:47 AM 
Subject: RE: [Elecraft] KX3 Field Ant. for 80/40/30 



I am well aware of that, Frank, and in fact I have multiple cores sitting here 
waiting for such measurements. However, performance of an isolated component is 
less important than overall system performance, where the matching to antenna 
impedance as well as counterpoise current routing and losses all play in. After 
the component testing to qualify different transformers as having low loss, I 
am planning to test different versions of resonant and non-resonant end-fed 
antennas against each other in pairs. The resonant (very high impedance) 
versons will include different transformer ratios. I may even include versions 
where the impedance transformation is performed with a tapped, tuned 
parallel-resonant circuit, which is the classic approach from the Zeppelin 
days. I may also include a center-fed dipole (conventional, K9YC?, sleeve 
around coax?). To be able to compare antenna systems with potentially small 
differences, I am set up with a pair of WSPRLite transmitters that let me run 
both antennas simultaneously in synchronization. In this type of testing one 
obtains two overlaid graphs representing the two antennas under test, versus 
time. Each value shows a composite number based on s/n ratios at a number of 
different receiving stations. Over time, the two curves tend to cross back and 
forth against each other, but over a few hours one can see whether one tends to 
dominate over the other. Transmission frequencies will not be exactly the same, 
but the difference will be very small. When done in my back yard, both antennas 
in a test will be influenced by all kinds of metal structures around it, 
including my tower, power lines, metal in the house, and the other antenna 
under test. I will minimize the latter by erecting the wires at 90 degrees 
angle, with the feed points close together, so that I can always reach both 
transmitters at the same time to push the start buttons at the same time. My 
main method of compensating for interactions with metal objects will be to swap 
the matching/feeding systems while keeping the radiators and transmitters in 
place. I like to deploy wire antennas in the field on 24 ft masts, so I will 
use two of those for the testing and arrange the two wires as inverted vee’s. 
For reasons of space, I will not include 80 m, so the two wires will be in the 
60+ foot range, except for the non-resonant version where 50+ feet are commonly 
used. For possible tests using center feed, I would use different arrangements 
that all resonate as ½ wavelength on 40. By comparing two antenna systems at a 
time, each time taking the winner to compare with the next antenna, I hope to 
determine an idea of what works best for me in field use. 

73, 
Erik K7TV 



From: donov...@starpower.net [mailto:donov...@starpower.net] 
Sent: Sunday, November 19, 2017 3:33 PM 
To: elecraft@mailman.qth.net 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30 


Its easy to measure transformer loss by measuring the loss through 

a pair of identical transformers connected to back-to-back. 



The loss in a single transformer will be half of the loss through the 

back-to-back pair. 



73 

Frank 

W3LPL 


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Re: [Elecraft] (OT) - Unplanned Discovery

[Josh]

Most, if not all of those certifications are for safety, not emissions. 
Further, I'm not at all convinced that compliance with FCC/CISPR standards 
ensures no RFI to a ham station. Especially if your interests are weak signal, 
EME, etc. 

73,
Josh W6XU

Sent from my mobile device

> Just because it has the side or back posted with all types of certifications 
> basically says  "they met specs at one time".
> 

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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[dyarnes]

Fred and All,

I think Morse is exactly what they are using with the signal lamps.  The 
article I read about this confirmed that.

Dave W7AQK



-

There was a recent URL posted involving using the venerable signal 
lamps for high speed communications between ships.? I don't think it was 
Morse however.

73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

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Re: [Elecraft] (OT) - Unplanned Discovery

[Bob McGraw K4TAX]

Don't put all switching power supplies in the same bucket.  There are 
very good ones that ARE QUIET, and then there are those that generate 
noise.   Just because it has the side or back posted with all types of 
certifications basically says  "they met specs at one time".


I have 3 Astron switching supplies that are quiet.   I have personally 
performed conducted and radiated emissions testing on those supplies.  
However, I've repaired several linear supplies an one switcher where the 
3 pin AC ground wire was insulated from the chassis by their beautiful 
paint job.    Those did create issues until the cause was discovered and 
corrected.


73

Bob, K4TAX


On 11/19/2017 7:39 PM, Barry wrote:

Rich,
    You just discovered the problem with switching power supplies. I'm 
unaware of any computer power supply that isn't a switcher, but for 
most 12 volt needs an analog supply should fix the problem. The only 
downside that I can see is weight; analog supplies can be a bunch 
heavier, but they are RF quiet.


    There some quiet switchers out there. You just need to do some 
research to discover those. One that is quiet is the Tentec. It is 
actually an Astron that Tentec did some work on. I think the one 
Elecraft sells is quiet. Bit, you really need to investigate before 
buying a switcher.


73,
Barry
K3NDM

-- Original Message --
From: "rich hurd WC3T" 
To: "stan levandowski" 
Cc: Elecraft@mailman.qth.net
Sent: 11/19/2017 7:31:48 PM
Subject: Re: [Elecraft] (OT) - Unplanned Discovery


Wow.

Going to try that.   Thanks for this great post.

On Sun, Nov 19, 2017 at 19:23 stan levandowski  
wrote:



Most people on this Reflector are well educated and intelligent.
Apparently, I'm the exception because this one got by me.  I'm only
owning up to this in the hope that it might help someone else on the
Reflector.

For the last couple of years I've been bothered by a high background
noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I 
attributed

this to the fact that my antenna has been in my attic for the last
fifteen years and propagation hasn't been good lately.


I just got official permission from the HOA to install an end fed wire
outside.  I was thrilled.  I put it up.  The darn thing wasn't any
better than the attic doublet.  Noisy as heck!  What a letdown!


So I'm laying in bed last night reflecting on how my little KX1 was the
only Elecraft radio that never had noise problems and seemed to have a
receiver quieter than my K3.


Whoa!  The KX1 always ran on batteries...could it be?


I just took delivery on a brand new Kx33 Low RFI power supply a couple
days ago. It was advertised in the last QST.   Previous to that, I've
been using a Samlex 1235M.  For the heck of it,  I connected my K2 
to an

SLA battery and the noise was still there.  But when I disconnected the
Kx33 power supply from the wall, the noise level dropped dramatically.
Then I switched to the Samlex and the noise came back.  Back on the
battery, the noise dropped again as long as the power supplies were
unplugged and dead.


I have a laptop next to the computer.  When I pulled the plug on the
laptop supply, the rest of the noise went away.  I was down to S0/S1 
and

CW signals were popping out all over the band again.  Running the
computer on its internal battery did NOT contribute any noise.  It was
the computer power supply.


Now that I am totally on batteries, I also appear to be immune from 
both

the gas furnace and the dishwasher motor both of which caused me
problems when using the AC supplies.  YES, I HAD CHOKES ON ALL 
SUPPLIES,

CABLES, WIRE.


I've been on the air all day with my new outside antenna, on battery
power,  making contacts near and far and I feel like I've hit the
jackpot.  Since I'm totally QRP and CW, being limited to batteries is
not an issue.


If you're going to check your own supplies out, remember they've got to
be OFF/UNPLUGGED from the wall. Just disconnecting them from the
radio/computer isn't enough.  It's RF.


73, Stan WB2LQF






1

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Rich Hurd / WC3T / DMR: 3142737
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Officer

for Scouting
Latitude: 40.761621 Longitude: -75.288988  (40°45.68' N 75°17.33' W) 
Grid:

*FN20is*
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[Elecraft] (OT) - Unplanned Discovery

[Jim Allen]

Before you throw the Samlex supply in the trash, have a look at 
http://w4kaz.com/images/fp1023/samlex_1223_rfi_mods_from_zl2df.pdf

and several other mod schemes found on the web.

73 Jim Allen W6OGC 

Sent from my iPad
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Re: [Elecraft] (OT) - Unplanned Discovery

[rich hurd WC3T]

Hi Barry,

I wasn't the one who experienced the epiphany; have to lay that at Stan's
feet.   :)

Frankly, it's not a big problem for me. However, it did connect a couple
dots in that I was at my brother-in-law's house operating on the battery
whilst visiting. I remarked that the noise floor was very low and just
attributed it to his QTH.   Never connected the fact that perhaps it was
just the local noise sources and I should be less concerned about QRM from
the neighbors and neighboring rooms, and more about what I was feeding the
rig and the other sources in the room.

I will now be spending some time rearranging things to try this out and get
my noise floor down even further.

On Sun, Nov 19, 2017 at 20:39 Barry  wrote:

> Rich,
>  You just discovered the problem with switching power supplies. I'm
> unaware of any computer power supply that isn't a switcher, but for most
> 12 volt needs an analog supply should fix the problem. The only downside
> that I can see is weight; analog supplies can be a bunch heavier, but
> they are RF quiet.
>
>  There some quiet switchers out there. You just need to do some
> research to discover those. One that is quiet is the Tentec. It is
> actually an Astron that Tentec did some work on. I think the one
> Elecraft sells is quiet. Bit, you really need to investigate before
> buying a switcher.
>
> 73,
> Barry
> K3NDM
>
> -- Original Message --
> From: "rich hurd WC3T" 
> To: "stan levandowski" 
> Cc: Elecraft@mailman.qth.net
> Sent: 11/19/2017 7:31:48 PM
> Subject: Re: [Elecraft] (OT) - Unplanned Discovery
>
> >Wow.
> >
> >Going to try that.   Thanks for this great post.
> >
> >On Sun, Nov 19, 2017 at 19:23 stan levandowski 
> >wrote:
> >
> >>Most people on this Reflector are well educated and intelligent.
> >>Apparently, I'm the exception because this one got by me.  I'm only
> >>owning up to this in the hope that it might help someone else on the
> >>Reflector.
> >>
> >>For the last couple of years I've been bothered by a high background
> >>noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I
> >>attributed
> >>this to the fact that my antenna has been in my attic for the last
> >>fifteen years and propagation hasn't been good lately.
> >>
> >>
> >>I just got official permission from the HOA to install an end fed wire
> >>outside.  I was thrilled.  I put it up.  The darn thing wasn't any
> >>better than the attic doublet.  Noisy as heck!  What a letdown!
> >>
> >>
> >>So I'm laying in bed last night reflecting on how my little KX1 was
> >>the
> >>only Elecraft radio that never had noise problems and seemed to have a
> >>receiver quieter than my K3.
> >>
> >>
> >>Whoa!  The KX1 always ran on batteries...could it be?
> >>
> >>
> >>I just took delivery on a brand new Kx33 Low RFI power supply a couple
> >>days ago. It was advertised in the last QST.   Previous to that, I've
> >>been using a Samlex 1235M.  For the heck of it,  I connected my K2 to
> >>an
> >>SLA battery and the noise was still there.  But when I disconnected
> >>the
> >>Kx33 power supply from the wall, the noise level dropped dramatically.
> >>Then I switched to the Samlex and the noise came back.  Back on the
> >>battery, the noise dropped again as long as the power supplies were
> >>unplugged and dead.
> >>
> >>
> >>I have a laptop next to the computer.  When I pulled the plug on the
> >>laptop supply, the rest of the noise went away.  I was down to S0/S1
> >>and
> >>CW signals were popping out all over the band again.  Running the
> >>computer on its internal battery did NOT contribute any noise.  It was
> >>the computer power supply.
> >>
> >>
> >>Now that I am totally on batteries, I also appear to be immune from
> >>both
> >>the gas furnace and the dishwasher motor both of which caused me
> >>problems when using the AC supplies.  YES, I HAD CHOKES ON ALL
> >>SUPPLIES,
> >>CABLES, WIRE.
> >>
> >>
> >>I've been on the air all day with my new outside antenna, on battery
> >>power,  making contacts near and far and I feel like I've hit the
> >>jackpot.  Since I'm totally QRP and CW, being limited to batteries is
> >>not an issue.
> >>
> >>
> >>If you're going to check your own supplies out, remember they've got
> >>to
> >>be OFF/UNPLUGGED from the wall. Just disconnecting them from the
> >>radio/computer isn't enough.  It's RF.
> >>
> >>
> >>73, Stan WB2LQF
> >>
> >>
> >>
> >>
> >>
> >>
> >>1
> >>
> >>__
> >>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 r...@wc3t.us
> >
> >--
> >---
> >72,
> >Rich Hurd / WC3T / DMR: 3142737
> >PA Army MARS, Northampton County RACES, EPA-ARRL 

[Elecraft] K3 - low power on SSB after antenna tuning

[Jim Stahl via Elecraft]

I’ve noticed an occasional situation where after tuning with the internal 
tuner, I have low power (about 20 watts on the K3 power display). I notice this 
in SSB only. A couple of dots on CW (I have CW in SSB enabled) clears the 
condition and returns things to normal power. (100 watts).  A power cycling 
will also clear things.

This seems to happen with a relatively  mis-matched antenna, athough the tuner 
has taken the indicated VSWR to under 1.5:1 or so.

Firmware V 5.60.


???

73  -  Jim  K8MR


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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

I am well aware of that, Frank, and in fact I have multiple cores sitting here 
waiting for such measurements. However, performance of an isolated component is 
less important than overall system performance, where the matching to antenna 
impedance as well as counterpoise current routing and losses all play in. After 
the component testing to qualify different transformers as having low loss, I 
am planning to test different versions of resonant and non-resonant end-fed 
antennas against each other in pairs. The resonant (very high impedance) 
versons will include different transformer ratios. I may even include versions 
where the impedance transformation is performed with a tapped, tuned 
parallel-resonant circuit, which is the classic approach from the Zeppelin 
days. I may also include a center-fed dipole (conventional, K9YC?, sleeve 
around coax?). To be able to compare antenna systems with potentially small 
differences, I am set up with a pair of WSPRLite transmitters that let me run 
both antennas simultaneously in synchronization. In this type of testing one 
obtains two overlaid graphs representing the two antennas under test, versus 
time. Each value shows a composite number based on s/n ratios at a number of 
different receiving stations. Over time, the two curves tend to cross back and 
forth against each other, but over a few hours one can see whether one tends to 
dominate over the other. Transmission frequencies will not be exactly the same, 
but the difference will be very small. When done in my back yard, both antennas 
in a test will be influenced by all kinds of metal structures around it, 
including my tower, power lines, metal in the house, and the other antenna 
under test. I will minimize the latter  by erecting the wires at 90 degrees 
angle, with the feed points close together, so that I can always reach both 
transmitters at the same time to push the start buttons at the same time. My 
main method of compensating for interactions with metal objects will be to swap 
the matching/feeding systems while keeping the radiators and transmitters in 
place. I like to deploy wire antennas in the field on 24 ft masts, so I will 
use two of those for the testing and arrange the two wires as inverted vee’s. 
For reasons of space, I will not include 80 m, so the two wires will be in the 
60+ foot range, except for the non-resonant version where 50+ feet are commonly 
used. For possible tests using center feed, I would use different arrangements 
that all resonate as ½ wavelength on 40. By comparing two antenna systems at a 
time, each time taking the winner to compare with the next antenna, I hope to 
determine an idea of what works best for me in field use.

 

73,

Erik K7TV

 

From: donov...@starpower.net [mailto:donov...@starpower.net] 
Sent: Sunday, November 19, 2017 3:33 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

 

Its easy to measure transformer loss by measuring the loss through

a pair of identical transformers connected to back-to-back.  

 

The loss in a single transformer will be half of the loss through the

back-to-back pair.

 

73

Frank

W3LPL

 

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Re: [Elecraft] (OT) - Unplanned Discovery

[Jim Brown]

Hi Stan,

You're far from the only one, but I've been preaching this for many 
years.  Take a look at this piece that I wrote for National Contest 
Journal a year or two ago.


http://k9yc.com/KillingReceiveNoise.pdf

An important first move is to search out and destroy every switching 
power supply you can find. Chances are there are dozens in your home, 
and dozens more in the homes of all of your neighbors.


73, Jim K9YC

On 11/19/2017 4:23 PM, stan levandowski wrote:
Apparently, I'm the exception because this one got by me. 



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Re: [Elecraft] (OT) - Unplanned Discovery

[stan levandowski]

Yeah, me too.  I bought it because I thought it would be "super clean" 
and really small.  But its contribution to my problem was pretty much 
unarguable:  Plug it in and I hear noise.  Unplug it and I don't hear 
noise.  The instructions that came with it specifically stated that the 
Kx33 should be placed the full length of the DC plug/cord away from the 
transceiver.  I did that but it didn't work for me.  I tried different 
outlets around the house too.  I put chokes on it.  No joy.



My post is not a complaint about the Kx33 mfgr, or the Samlex 
Corporation or anyone else.  Maybe it's my transceiver, maybe it's my 
equipment, maybe it's my utility service.I'm not qualified to say or 
knowledgeable to analyze.



I simply wanted to suggest to others in the Elecraft family that if they 
have "noise" it might be right under their nose and worth checking out 
vs. blaming propagation or the next door neighbor  ;-)



P.S. -  My "noise problem" is about two years old and coincides with the 
purchase of my first switch mode power supply.  I had a perfectly good 
linear supply made by Astron but I deemed it too big and klutzy and 
dumped it.  Another one of my great decisions



73, Stan WB2LQF


Nov 19, 2017 at 08:05 PM, JT Croteau wrote:


I'm really surprised you had an issue with the KX33 supply.

- JT


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Re: [Elecraft] (OT) - Unplanned Discovery

[Barry]

Rich,
You just discovered the problem with switching power supplies. I'm 
unaware of any computer power supply that isn't a switcher, but for most 
12 volt needs an analog supply should fix the problem. The only downside 
that I can see is weight; analog supplies can be a bunch heavier, but 
they are RF quiet.


There some quiet switchers out there. You just need to do some 
research to discover those. One that is quiet is the Tentec. It is 
actually an Astron that Tentec did some work on. I think the one 
Elecraft sells is quiet. Bit, you really need to investigate before 
buying a switcher.


73,
Barry
K3NDM

-- Original Message --
From: "rich hurd WC3T" 
To: "stan levandowski" 
Cc: Elecraft@mailman.qth.net
Sent: 11/19/2017 7:31:48 PM
Subject: Re: [Elecraft] (OT) - Unplanned Discovery


Wow.

Going to try that.   Thanks for this great post.

On Sun, Nov 19, 2017 at 19:23 stan levandowski  
wrote:



Most people on this Reflector are well educated and intelligent.
Apparently, I'm the exception because this one got by me.  I'm only
owning up to this in the hope that it might help someone else on the
Reflector.

For the last couple of years I've been bothered by a high background
noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I 
attributed

this to the fact that my antenna has been in my attic for the last
fifteen years and propagation hasn't been good lately.


I just got official permission from the HOA to install an end fed wire
outside.  I was thrilled.  I put it up.  The darn thing wasn't any
better than the attic doublet.  Noisy as heck!  What a letdown!


So I'm laying in bed last night reflecting on how my little KX1 was 
the

only Elecraft radio that never had noise problems and seemed to have a
receiver quieter than my K3.


Whoa!  The KX1 always ran on batteries...could it be?


I just took delivery on a brand new Kx33 Low RFI power supply a couple
days ago. It was advertised in the last QST.   Previous to that, I've
been using a Samlex 1235M.  For the heck of it,  I connected my K2 to 
an
SLA battery and the noise was still there.  But when I disconnected 
the

Kx33 power supply from the wall, the noise level dropped dramatically.
Then I switched to the Samlex and the noise came back.  Back on the
battery, the noise dropped again as long as the power supplies were
unplugged and dead.


I have a laptop next to the computer.  When I pulled the plug on the
laptop supply, the rest of the noise went away.  I was down to S0/S1 
and

CW signals were popping out all over the band again.  Running the
computer on its internal battery did NOT contribute any noise.  It was
the computer power supply.


Now that I am totally on batteries, I also appear to be immune from 
both

the gas furnace and the dishwasher motor both of which caused me
problems when using the AC supplies.  YES, I HAD CHOKES ON ALL 
SUPPLIES,

CABLES, WIRE.


I've been on the air all day with my new outside antenna, on battery
power,  making contacts near and far and I feel like I've hit the
jackpot.  Since I'm totally QRP and CW, being limited to batteries is
not an issue.


If you're going to check your own supplies out, remember they've got 
to

be OFF/UNPLUGGED from the wall. Just disconnecting them from the
radio/computer isn't enough.  It's RF.


73, Stan WB2LQF






1

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---
72,
Rich Hurd / WC3T / DMR: 3142737
PA Army MARS, Northampton County RACES, EPA-ARRL Public Information 
Officer

for Scouting
Latitude: 40.761621 Longitude: -75.288988  (40°45.68' N 75°17.33' W) 
Grid:

*FN20is*
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[Elecraft] Elecraft CW Net Report

[kevinr]

Good Evening,

    The forty meter net just ended.  Conditions were a little noisy 
with various types of QSB.  From Alaska there was a flutter, from North 
Dakota there was none, and from California there was a slow, rolling 
wave (must be the surfer effect :).  Twenty meters had QSB too but 
fantastic signals from mostly the Eastern US. Ken, working from the Red 
River Valley, was the only westerner. While I did get one report of 13 
degrees the rest were pretty seasonal.



   On 14050.5 kHz at 2300z:

NO8V - John - MI

W0CZ - Ken - ND

K6XK - Roy - IA

K4JPN - Steve - GA


  On 7045.5 kHz at 0100z:

W0CZ - Ken - ND

K0DTJ - Brian - CA  TNX for the QSP work

K6PJV - Dale - CA

KN5L - John - TX

KG7V - Marv - WA

KL7CW - Rick - AK

   Until next week : Have a Happy and Safe Thanksgiving.

73,

 Kevin.  KD5ONS

-

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Re: [Elecraft] (OT) - Unplanned Discovery

[JT Croteau]

I'm really surprised you had an issue with the KX33 supply.

- JT

On Sun, Nov 19, 2017 at 7:31 PM, rich hurd WC3T  wrote:
> Wow.
>
> Going to try that.   Thanks for this great post.
>
> On Sun, Nov 19, 2017 at 19:23 stan levandowski  wrote:
>
>> Most people on this Reflector are well educated and intelligent.
>> Apparently, I'm the exception because this one got by me.  I'm only
>> owning up to this in the hope that it might help someone else on the
>> Reflector.
>>
>> For the last couple of years I've been bothered by a high background
>> noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I attributed
>> this to the fact that my antenna has been in my attic for the last
>> fifteen years and propagation hasn't been good lately.
>>
>>
>> I just got official permission from the HOA to install an end fed wire
>> outside.  I was thrilled.  I put it up.  The darn thing wasn't any
>> better than the attic doublet.  Noisy as heck!  What a letdown!
>>
>>
>> So I'm laying in bed last night reflecting on how my little KX1 was the
>> only Elecraft radio that never had noise problems and seemed to have a
>> receiver quieter than my K3.
>>
>>
>> Whoa!  The KX1 always ran on batteries...could it be?
>>
>>
>> I just took delivery on a brand new Kx33 Low RFI power supply a couple
>> days ago. It was advertised in the last QST.   Previous to that, I've
>> been using a Samlex 1235M.  For the heck of it,  I connected my K2 to an
>> SLA battery and the noise was still there.  But when I disconnected the
>> Kx33 power supply from the wall, the noise level dropped dramatically.
>> Then I switched to the Samlex and the noise came back.  Back on the
>> battery, the noise dropped again as long as the power supplies were
>> unplugged and dead.
>>
>>
>> I have a laptop next to the computer.  When I pulled the plug on the
>> laptop supply, the rest of the noise went away.  I was down to S0/S1 and
>> CW signals were popping out all over the band again.  Running the
>> computer on its internal battery did NOT contribute any noise.  It was
>> the computer power supply.
>>
>>
>> Now that I am totally on batteries, I also appear to be immune from both
>> the gas furnace and the dishwasher motor both of which caused me
>> problems when using the AC supplies.  YES, I HAD CHOKES ON ALL SUPPLIES,
>> CABLES, WIRE.
>>
>>
>> I've been on the air all day with my new outside antenna, on battery
>> power,  making contacts near and far and I feel like I've hit the
>> jackpot.  Since I'm totally QRP and CW, being limited to batteries is
>> not an issue.
>>
>>
>> If you're going to check your own supplies out, remember they've got to
>> be OFF/UNPLUGGED from the wall. Just disconnecting them from the
>> radio/computer isn't enough.  It's RF.
>>
>>
>> 73, Stan WB2LQF
>>
>>
>>
>>
>>
>>
>> 1
>>
>> __
>> 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 r...@wc3t.us
>
> --
> ---
> 72,
> Rich Hurd / WC3T / DMR: 3142737
> PA Army MARS, Northampton County RACES, EPA-ARRL Public Information Officer
> for Scouting
> Latitude: 40.761621 Longitude: -75.288988  (40°45.68' N 75°17.33' W) Grid:
> *FN20is*
> __
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> Message delivered to jt.to...@gmail.com
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Re: [Elecraft] (OT) - Unplanned Discovery

[rich hurd WC3T]

Wow.

Going to try that.   Thanks for this great post.

On Sun, Nov 19, 2017 at 19:23 stan levandowski  wrote:

> Most people on this Reflector are well educated and intelligent.
> Apparently, I'm the exception because this one got by me.  I'm only
> owning up to this in the hope that it might help someone else on the
> Reflector.
>
> For the last couple of years I've been bothered by a high background
> noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I attributed
> this to the fact that my antenna has been in my attic for the last
> fifteen years and propagation hasn't been good lately.
>
>
> I just got official permission from the HOA to install an end fed wire
> outside.  I was thrilled.  I put it up.  The darn thing wasn't any
> better than the attic doublet.  Noisy as heck!  What a letdown!
>
>
> So I'm laying in bed last night reflecting on how my little KX1 was the
> only Elecraft radio that never had noise problems and seemed to have a
> receiver quieter than my K3.
>
>
> Whoa!  The KX1 always ran on batteries...could it be?
>
>
> I just took delivery on a brand new Kx33 Low RFI power supply a couple
> days ago. It was advertised in the last QST.   Previous to that, I've
> been using a Samlex 1235M.  For the heck of it,  I connected my K2 to an
> SLA battery and the noise was still there.  But when I disconnected the
> Kx33 power supply from the wall, the noise level dropped dramatically.
> Then I switched to the Samlex and the noise came back.  Back on the
> battery, the noise dropped again as long as the power supplies were
> unplugged and dead.
>
>
> I have a laptop next to the computer.  When I pulled the plug on the
> laptop supply, the rest of the noise went away.  I was down to S0/S1 and
> CW signals were popping out all over the band again.  Running the
> computer on its internal battery did NOT contribute any noise.  It was
> the computer power supply.
>
>
> Now that I am totally on batteries, I also appear to be immune from both
> the gas furnace and the dishwasher motor both of which caused me
> problems when using the AC supplies.  YES, I HAD CHOKES ON ALL SUPPLIES,
> CABLES, WIRE.
>
>
> I've been on the air all day with my new outside antenna, on battery
> power,  making contacts near and far and I feel like I've hit the
> jackpot.  Since I'm totally QRP and CW, being limited to batteries is
> not an issue.
>
>
> If you're going to check your own supplies out, remember they've got to
> be OFF/UNPLUGGED from the wall. Just disconnecting them from the
> radio/computer isn't enough.  It's RF.
>
>
> 73, Stan WB2LQF
>
>
>
>
>
>
> 1
>
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> Message delivered to r...@wc3t.us

-- 
---
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PA Army MARS, Northampton County RACES, EPA-ARRL Public Information Officer
for Scouting
Latitude: 40.761621 Longitude: -75.288988  (40°45.68' N 75°17.33' W) Grid:
*FN20is*
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Re: [Elecraft] (OT) - Unplanned Discovery

[Wayne Burdick]

Great story, Stan. Now you know why the K3/K3S/KX2/KX3 all have data modes you 
can use without a computer :)

73,
Wayne
N6KR


> On Nov 19, 2017, at 4:23 PM, stan levandowski  wrote:
> 
> Most people on this Reflector are well educated and intelligent.  Apparently, 
> I'm the exception because this one got by me.  I'm only owning up to this in 
> the hope that it might help someone else on the Reflector. 
> 
> For the last couple of years I've been bothered by a high background noise 
> level.   It happened on my K1, K2, K3, KX2 and KX3.   I attributed this to 
> the fact that my antenna has been in my attic for the last fifteen years and 
> propagation hasn't been good lately.
> 
> 
> I just got official permission from the HOA to install an end fed wire 
> outside.  I was thrilled.  I put it up.  The darn thing wasn't any better 
> than the attic doublet.  Noisy as heck!  What a letdown!
> 
> 
> So I'm laying in bed last night reflecting on how my little KX1 was the only 
> Elecraft radio that never had noise problems and seemed to have a receiver 
> quieter than my K3.
> 
> 
> Whoa!  The KX1 always ran on batteries...could it be?
> 
> 
> I just took delivery on a brand new Kx33 Low RFI power supply a couple days 
> ago. It was advertised in the last QST.   Previous to that, I've been using a 
> Samlex 1235M.  For the heck of it,  I connected my K2 to an SLA battery and 
> the noise was still there.  But when I disconnected the Kx33 power supply 
> from the wall, the noise level dropped dramatically.  Then I switched to the 
> Samlex and the noise came back.  Back on the battery, the noise dropped again 
> as long as the power supplies were unplugged and dead.
> 
> 
> I have a laptop next to the computer.  When I pulled the plug on the laptop 
> supply, the rest of the noise went away.  I was down to S0/S1 and CW signals 
> were popping out all over the band again.  Running the computer on its 
> internal battery did NOT contribute any noise.  It was the computer power 
> supply.
> 
> 
> Now that I am totally on batteries, I also appear to be immune from both the 
> gas furnace and the dishwasher motor both of which caused me problems when 
> using the AC supplies.  YES, I HAD CHOKES ON ALL SUPPLIES, CABLES, WIRE.
> 
> 
> I've been on the air all day with my new outside antenna, on battery power,  
> making contacts near and far and I feel like I've hit the jackpot.  Since I'm 
> totally QRP and CW, being limited to batteries is not an issue.
> 
> 
> If you're going to check your own supplies out, remember they've got to be 
> OFF/UNPLUGGED from the wall. Just disconnecting them from the radio/computer 
> isn't enough.  It's RF.
> 
> 
> 73, Stan WB2LQF
> 
> 
> 
> 
> 
> 
> 1
> 
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[Elecraft] (OT) - Unplanned Discovery

[stan levandowski]

Most people on this Reflector are well educated and intelligent.  
Apparently, I'm the exception because this one got by me.  I'm only 
owning up to this in the hope that it might help someone else on the 
Reflector. 


For the last couple of years I've been bothered by a high background 
noise level.   It happened on my K1, K2, K3, KX2 and KX3.   I attributed 
this to the fact that my antenna has been in my attic for the last 
fifteen years and propagation hasn't been good lately.



I just got official permission from the HOA to install an end fed wire 
outside.  I was thrilled.  I put it up.  The darn thing wasn't any 
better than the attic doublet.  Noisy as heck!  What a letdown!



So I'm laying in bed last night reflecting on how my little KX1 was the 
only Elecraft radio that never had noise problems and seemed to have a 
receiver quieter than my K3.



Whoa!  The KX1 always ran on batteries...could it be?


I just took delivery on a brand new Kx33 Low RFI power supply a couple 
days ago. It was advertised in the last QST.   Previous to that, I've 
been using a Samlex 1235M.  For the heck of it,  I connected my K2 to an 
SLA battery and the noise was still there.  But when I disconnected the 
Kx33 power supply from the wall, the noise level dropped dramatically.  
Then I switched to the Samlex and the noise came back.  Back on the 
battery, the noise dropped again as long as the power supplies were 
unplugged and dead.



I have a laptop next to the computer.  When I pulled the plug on the 
laptop supply, the rest of the noise went away.  I was down to S0/S1 and 
CW signals were popping out all over the band again.  Running the 
computer on its internal battery did NOT contribute any noise.  It was 
the computer power supply.



Now that I am totally on batteries, I also appear to be immune from both 
the gas furnace and the dishwasher motor both of which caused me 
problems when using the AC supplies.  YES, I HAD CHOKES ON ALL SUPPLIES, 
CABLES, WIRE.



I've been on the air all day with my new outside antenna, on battery 
power,  making contacts near and far and I feel like I've hit the 
jackpot.  Since I'm totally QRP and CW, being limited to batteries is 
not an issue.



If you're going to check your own supplies out, remember they've got to 
be OFF/UNPLUGGED from the wall. Just disconnecting them from the 
radio/computer isn't enough.  It's RF.



73, Stan WB2LQF






1

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Re: [Elecraft] FS: K3DSPLPF

[Don Wilhelm]

Mike,

Order from Elecraft.  K3DSPLPF - look in Spare Parts on the website.

73,
Don W3FPR

On 11/19/2017 6:50 PM, VE3WDM wrote:

I will take it if still available?

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Re: [Elecraft] FS: K3DSPLPF

[VE3WDM]

I will take it if still available?
Mike 
VE3WDM



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Re: [Elecraft] Adding Sub receiver in K3

[VE3WDM]

Thank very much for the fast feedback
Mike
VE3WDM



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[donovanf]

Its easy to measure transformer loss by measuring the loss through 
a pair of identical transformers connected to back-to-back. 


The loss in a single transformer will be half of the loss through the 
back-to-back pair. 


73 
Frank 
W3LPL 

- Original Message -

From: "Erik Basilier"  
To: "Bill Frantz"  
Cc: elecraft@mailman.qth.net 
Sent: Sunday, November 19, 2017 10:14:41 PM 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30 

Bill, I am aware of Jim's innovative way of achieving center feed while 
seemingly attaching the feeder to the end. It should be useful in some 
situations. However, the thread creator wanted coverage of 4 bands with one 
antenna, and my personal interest right now is also solutions that cover 
serveral bands without adjustments and compromises. With that as the goal, I 
see no theoretical reason to want center feed. Only by feeding at the end can 
you get approximately the same impedance for each band, without moving the 
feedpoint, for so many bands. (That said, if you compare reality side-by-side 
to a map, reality tends to win. It would be interesting to compare side-by-side 
to make sure that the high-ratio transformer isn't lossy enough to hurt 
performance.) If you are looking at a single band, with a 1/2 wave vertical 
wire. The current distribution should theoretically be the same whether we feed 
it at the bottom or if we move the feed point to the center at the cost of 1/4 
wav
  
elength of additional coax plus the cost of the common mode choke (but there 
may be another justification to have the choke anyway). If one is willing to 
compromise the requirement of covering several bands with very good match, 
there is also the option of Off-Center-Feed, which can allow operation on 
several bands, but the match on most or all bands will be a compromise that 
likely forces the use of a tuner, similar to the situation with an end-fed with 
9:1 impedance transformer. If you compare the OCF with the end-fed with 9:1 
impedance transformer, it is not clear to me which one has the edge in 
practical use (assuming both have the antenna wire suspended and shaped 
similarly). For the OCF the results will depend on the selection of feedpoint, 
and for the end-fed there is room for a wide range of wire lengths that are 
non-resonant and should produce "medium impedance". One can easily find 
suggestions online for both designs. However, it seems to me that the 9:1 fans 
are 
more prone to use low elevations and shapes that reduce performance. 

73, 
Erik K7TV 

-Original Message- 
From: Bill Frantz [mailto:fra...@pwpconsult.com] 
Sent: Sunday, November 19, 2017 1:03 PM 
To: Erik Basilier  
Cc: 'JT Croteau' ; elecraft@mailman.qth.net 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30 

A useful post Erik. 

Also useful is the "pseudo end-fed" design that K9YC shows on 
 starting at page 70. This design is really 
a center fed dipole using the outside of the feed line coax as one half of the 
dipole and an extension of the center conductor as the other. The RF-electrical 
length of the feed line outside is controlled by a common-mode choke on the 
feed line. 

I built one of these for 30 meters and found that the best tuning occured when 
the coax shield between the common-mode choke and the "center" feed location 
was slightly shorter than the other half of the dipole. 

73 Bill AE6JV 


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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

Bill, I am aware of Jim's innovative way of achieving center feed while 
seemingly attaching the feeder to the end. It should be useful in some 
situations. However, the thread creator wanted coverage of 4 bands with one 
antenna, and my personal interest right now is also solutions that cover 
serveral bands without adjustments and compromises. With that as the goal, I 
see no theoretical reason to want center feed. Only by feeding at the end can 
you get approximately the same impedance for each band, without moving the 
feedpoint, for so many bands. (That said, if you compare reality side-by-side 
to a map, reality tends to win. It would be interesting to compare side-by-side 
to make sure that the high-ratio transformer isn't lossy enough to hurt 
performance.) If you are looking at a single band, with a 1/2 wave vertical 
wire. The current distribution should theoretically be the same whether we feed 
it at the bottom or if we move the feed point to the center at the cost of 1/4 
wav
 elength of additional coax plus the cost of the common mode choke (but there 
may be another justification to have the choke anyway).  If one is willing to 
compromise the requirement of covering several bands with very good match, 
there is also the option of Off-Center-Feed, which can allow operation on 
several bands, but the match on most or all bands will be a compromise that 
likely forces the use of a tuner, similar to the situation with an end-fed with 
9:1 impedance transformer. If you compare the OCF with the end-fed with 9:1 
impedance transformer, it is not clear to me which one has the edge in 
practical use (assuming both have the antenna wire suspended and shaped 
similarly). For the OCF the results will depend on the selection of feedpoint, 
and for the end-fed there is room for a wide range of wire lengths that are 
non-resonant and should produce "medium impedance". One can easily find 
suggestions online for both designs. However, it seems to me that the 9:1 fans 
are 
 more prone to use low elevations and shapes that reduce performance. 

73,
Erik K7TV

-Original Message-
From: Bill Frantz [mailto:fra...@pwpconsult.com] 
Sent: Sunday, November 19, 2017 1:03 PM
To: Erik Basilier 
Cc: 'JT Croteau' ; elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

A useful post Erik.

Also useful is the "pseudo end-fed" design that K9YC shows on 
 starting at page 70. This design is really 
a center fed dipole using the outside of the feed line coax as one half of the 
dipole and an extension of the center conductor as the other. The RF-electrical 
length of the feed line outside is controlled by a common-mode choke on the 
feed line.

I built one of these for 30 meters and found that the best tuning occured when 
the coax shield between the common-mode choke and the "center" feed location 
was slightly shorter than the other half of the dipole.

73 Bill AE6JV


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Re: [Elecraft] Adding Sub receiver in K3

[Don Wilhelm]

Mike,

There is no mention of a specific level DSP board in the KRX3 
installation manual, so it should work with any existing DSP board.


73,
Don W3FPR

On 11/19/2017 3:52 PM, Mike Weir wrote:

Good evening all I have a K3 and want to add the sub receiver I have the new 
KSYN3A in my K3 but is my DSP board comparable? My DSP board in the K3 is rev C

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Re: [Elecraft] Adding Sub receiver in K3

[Grant Youngman]

The “c” board is fine. If you haven’t done it, you might want to add the LPF 
board to it (K3DSPLPF) — that will make it functionally equivalent to a “D” 
board. Not required, though. 

Grant NQ5T

Sent from my iPhone

> On Nov 19, 2017, at 3:52 PM, Mike Weir  wrote:
> 
> Good evening all I have a K3 and want to add the sub receiver I have the new 
> KSYN3A in my K3 but is my DSP board comparable? My DSP board in the K3 is rev 
> C
> Mike
> 
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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

That group sounds interesting, thanks.
73,
Erik K7TV

-Original Message-
From: VE3GAM [mailto:ve3...@rogers.com] 
Sent: Sunday, November 19, 2017 12:09 PM
To: Erik Basilier ; 'JT Croteau' ;
elecraft@mailman.qth.net
Cc: Al VE3GAM 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30

there is an End Fed Half Wave Antenna group on Facebook started up by N4LQ.
it certainly promotes the EFHW fed with a 49:1 transformer. Steve loves the
EFHW, but really does not have much love for 9:1 unun antenna. still, it is
an interesting group to monitor.

al ve3gam


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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Fred Jensen]

True ... however "someone" must be using Morse or there wouldn't be any 
communications to intercept. [:-)  Maybe the US Navy is intercepting 
us?  There was a recent URL posted involving using the venerable signal 
lamps for high speed communications between ships.  I don't think it was 
Morse however.


73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 11/19/2017 1:24 AM, Richard Lamont wrote:

On 18/11/17 03:45, Ron D'Eau Claire wrote:


http://www.navy.mil/submit/display.asp?story_id=92864

The people being trained by the US Navy to read Morse are intercept
operators.

"Morse code is just one tool that cryptologic technician (collection)
Sailors use as members of the Navy's Information Warfare community to
perform collection, analysis and reporting on communication signals."

There's nothing in this press release to suggest that the US Navy is
reverting to Morse for two-way communication.

73,
Richard G4DYA



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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Fred Jensen]

True ... however "someone" must be using Morse or there wouldn't be any 
communications to intercept. [:-)  Maybe the US Navy is intercepting 
us?  There was a recent URL posted involving using the venerable signal 
lamps for high speed communications between ships.  I don't think it was 
Morse however.


73,

Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 11/19/2017 1:24 AM, Richard Lamont wrote:

On 18/11/17 03:45, Ron D'Eau Claire wrote:


http://www.navy.mil/submit/display.asp?story_id=92864

The people being trained by the US Navy to read Morse are intercept
operators.

"Morse code is just one tool that cryptologic technician (collection)
Sailors use as members of the Navy's Information Warfare community to
perform collection, analysis and reporting on communication signals."

There's nothing in this press release to suggest that the US Navy is
reverting to Morse for two-way communication.

73,
Richard G4DYA



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[Elecraft] Adding Sub receiver in K3

[Mike Weir]

Good evening all I have a K3 and want to add the sub receiver I have the new 
KSYN3A in my K3 but is my DSP board comparable? My DSP board in the K3 is rev C
Mike
VE3WDM
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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Bill Frantz]

A useful post Erik.

Also useful is the "pseudo end-fed" design that K9YC shows on 
 starting at page 70. This 
design is really a center fed dipole using the outside of the 
feed line coax as one half of the dipole and an extension of the 
center conductor as the other. The RF-electrical length of the 
feed line outside is controlled by a common-mode choke on the 
feed line.


I built one of these for 30 meters and found that the best 
tuning occured when the coax shield between the common-mode 
choke and the "center" feed location was slightly shorter than 
the other half of the dipole.


73 Bill AE6JV

On 11/19/17 at 12:22 AM, ebasil...@cox.net (Erik Basilier) wrote:


End-fed antennas have gotten popular lately. When I look closer I see two
different popular approaches.


---
Bill Frantz| "I wish there was a knob on the TV to turn 
up the
408-356-8506   | intelligence.  There's a knob called 
"brightness", but

www.pwpconsult.com | it doesn't work. -- Gallagher

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[Elecraft] Elecraft (and more) Items For Sale

[Ken Alexander]

I'm moving in 2018 and can't take these items with me.  Note that all prices 
include shipping to CONUS or Canada.
1.  Elecraft XV432 70cm transverter with optional crystal oven. Built by me.  
Aligned & tested by Don Wilhelm W3FPR.  28 MHz I.F.  5W in, 20W out.  Can be 
reconfigured for other input levels.  Comes with manuals and power cable.  U.S. 
$350 
2.  Elecraft XV144 2m all mode transverter.  New, unbuilt kit.  Comes with 
optional crystal oven.  28 MHz I.F.  U.S.$450
3.  Elecraft W2 Wattmeter with 200W sensor for 144 - 450 MHz.  U.S. $200
4.  RF Concepts  RFC-4-110  70cm amplifier  15W in - 100W out.  Comes with 
manual and power cable. U.S. $225
5.  80W  All Mode 2m Amplifier.  Designed by W6PQL.  Built for me by Ed, KL7UW. 
 New, comes with docs by KL7UW and power cables.  Set up to take 1W input from 
a KX3 to give full output.  U.S. $275Read about it here: 2 Meter 80W All Mode 
Amplifier
Thanks for your interest!
73,
KenVE3HLS


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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[VE3GAM]

there is an End Fed Half Wave Antenna group on Facebook
started up by N4LQ. it certainly promotes the EFHW fed with
a 49:1 transformer. Steve loves the EFHW, but really does not
have much love for 9:1 unun antenna. still, it is an interesting
group to monitor.

al ve3gam

--
From: "Erik Basilier" 
Sent: Sunday, November 19, 2017 3:22 AM
To: "'JT Croteau'" ; 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30


End-fed antennas have gotten popular lately. When I look closer I see two
different popular approaches.

The first uses a 9:1 impedance transformer in combination with a wire 
length

that is not resonant on any band. The idea is that (assuming there is no
significant feedline length) you have a medium impedance (450 ohms) on the
antenna side of the transformer, and because the wire is not resonant so 
you

might have an impedance into the wire that is also "medium". By adjusting
the wire length, you might get pretty close to 450 ohms on one or two 
bands,
and with a wide range tuner you can probably get below swr 2:1 for the 
radio

PA to see.

The second approach, used by MyAntennas and others seems to use a
transformer with much higher impedance ratio. One way to construct such a
transformer would be to cascade two 9:1 units for an effective ratio of
81:1. This would mean the wire should present an impedance of 4000 ohms or
so. Another way would be using a single tranformer with a higher ratio. 
The
impedance ratio is the square of the turns ratio. With a turns ratio of 
9:1

you should again get to about 4000 ohms. Somewhere I saw somebody using an
8:1 turns ratio for an ideal antenna wire impedance of about 3200 ohms.
These impedance levels are achieved by using a resonant wire.

I don't know how you arrived at your parameters, but your wire length is 
too
close to resonance on 80 and 40. Your transformer ratio wants a 
non-resonant
wire, so you might see better results if you shorten the wire 
significantly
and keep using the KX3 ATU. Alternatively, you could replace the 
transformer

for a much higher impedance ratio, in which case you can probably operate
with the tuner bypassed at least on 80 and 40 with a well adjusted wire
length. With this approach you want the wire resonant on each band. It
should be easy to achieve resonance on 80, 40, 20 and 10. As you double 
the

frequency, you are changing the number of half wavelengths covered by the
wire; the end feedpoint is always at the end of one of these half
wavelengths, and thus you get the very high impedance that you seek. 30
meters does not fit as clearly into this scheme. The commercial versions 
use

a small coil in the wire located close to the transformer end, and seem to
be able to achieve a reasoable match for all the bands 80 and up without
using a tuner. Now if you had placed the feedpoint in the center you would
not have been able to get this consistency of feedpoint impedance from 
band

to band. As I see it, this is a major reason for the popularity of the
end-fed approach as contrasted to the conventional center-fed approach. 
Note
that the 30m coverage of the 80 meter and up design is not replicated if 
you
try the same approach with half the wire length. In this case you will 
need

a tuner to get reasonable swr on 30.

An important consideration is antenna height. We all know that antennas
usually work better when placed higher. Looking a bit closer, we can look
beyond the general installation height and consider the height(s) of the
antenna part(s) that carry the most current. Antenna modelling may 
calculate
the field as resulting from current levels in different individual pieces 
of
the wire, and then it makes sense to elevate those portions more than 
other

parts of the wire that carry less current. Another reason for this is the
effect of ground losses. Jim Brown, in his article that he just linked to,
shows that ground losses get worse the closer a vertical antenna is to
ground. This makes sense as currents in the lossy soil are caused by
induction from currents in the antenna. When we look at the current
distribution within the vertical antenna wire it again makes sense to 
place

the part(s) of the wire with high current higher rather than lower. One of
the simplest portable antennas is a short wire or whip of a quarter wave 
or

less. It will have a low feedpoint impedance that can probably be matched
reasonably without a tuner or with a limited-range tuner. However, with a
low impedance comes a current maximum at the feedpoint. This often means
close to the ground, so even with a good set of elevated radials,
considerable ground losses could be expected. (An actual connection to the
soil would generally be much worse, unless you bury a lot of wires.) With 
a

longer wire (1/2 wavelengh at the lowest band) we can have a very high
feedpoint impedance, very low feedpoint current, and more elevated

Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Eric J]

Maybe not, but having intercept operators learn Morse code implies that 
SOMEBODY is using it that the US military wants to listen to. So Morse code is 
not dead.

Eric KE6US

On 11/19/2017 1:24 AM, Richard Lamont wrote:

On 18/11/17 03:45, Ron D'Eau Claire wrote:



http://www.navy.mil/submit/display.asp?story_id=92864



The people being trained by the US Navy to read Morse are intercept
operators.

"Morse code is just one tool that cryptologic technician (collection)
Sailors use as members of the Navy's Information Warfare community to
perform collection, analysis and reporting on communication signals."

There's nothing in this press release to suggest that the US Navy is
reverting to Morse for two-way communication.

73,
Richard G4DYA
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.



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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Lynn W. Taylor, WB6UUT]

If the wire is near an even multiple of 1/4 wave (1/2 wave, one full 
wave, 1 1/2 wave, etc.) then the impedance at the end of the wire is 
going to be very high.


If the wire is near an odd multiple of 1/4 wave (1/4 wave, 3/4 wave, 1 
1/4 wave) then the impedance will be low.


If you're expecting a high impedance and you have a 3/4 wave wire, you 
may have trouble getting a match with a 9:1 balun.


That's oversimplified, of course.

The reason "pseudo-random" antennas around 53' are popular is that 
length isn't resonant on any popular ham band, and you can start making 
assumptions about how it'll work.


73 -- Lynn

On 11/19/2017 12:22 AM, Erik Basilier wrote:

End-fed antennas have gotten popular lately. When I look closer I see two
different popular approaches.

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[JT Croteau]

Thanks for all the comments and suggestions.  Some great info to mull over.

N1ESE

On Sun, Nov 19, 2017 at 6:36 AM, Igor Sokolov  wrote:
> Very useful post Erik,
>
> Thank you
>
> 73, Igor UA9CDC
>
>
> 19.11.2017 13:22, Erik Basilier пишет:
>>
>> End-fed antennas have gotten popular lately. When I look closer I see two
>> different popular approaches.
>>
>> The first uses a 9:1 impedance transformer in combination with a wire
>> length
>> that is not resonant on any band. The idea is that (assuming there is no
>> significant feedline length) you have a medium impedance (450 ohms) on the
>> antenna side of the transformer, and because the wire is not resonant so
>> you
>> might have an impedance into the wire that is also "medium". By adjusting
>> the wire length, you might get pretty close to 450 ohms on one or two
>> bands,
>> and with a wide range tuner you can probably get below swr 2:1 for the
>> radio
>> PA to see.
>>
>> The second approach, used by MyAntennas and others seems to use a
>> transformer with much higher impedance ratio. One way to construct such a
>> transformer would be to cascade two 9:1 units for an effective ratio of
>> 81:1. This would mean the wire should present an impedance of 4000 ohms or
>> so. Another way would be using a single tranformer with a higher ratio.
>> The
>> impedance ratio is the square of the turns ratio. With a turns ratio of
>> 9:1
>> you should again get to about 4000 ohms. Somewhere I saw somebody using an
>> 8:1 turns ratio for an ideal antenna wire impedance of about 3200 ohms.
>> These impedance levels are achieved by using a resonant wire.
>>
>> I don't know how you arrived at your parameters, but your wire length is
>> too
>> close to resonance on 80 and 40. Your transformer ratio wants a
>> non-resonant
>> wire, so you might see better results if you shorten the wire
>> significantly
>> and keep using the KX3 ATU. Alternatively, you could replace the
>> transformer
>> for a much higher impedance ratio, in which case you can probably operate
>> with the tuner bypassed at least on 80 and 40 with a well adjusted wire
>> length. With this approach you want the wire resonant on each band. It
>> should be easy to achieve resonance on 80, 40, 20 and 10. As you double
>> the
>> frequency, you are changing the number of half wavelengths covered by the
>> wire; the end feedpoint is always at the end of one of these half
>> wavelengths, and thus you get the very high impedance that you seek. 30
>> meters does not fit as clearly into this scheme. The commercial versions
>> use
>> a small coil in the wire located close to the transformer end, and seem to
>> be able to achieve a reasoable match for all the bands 80 and up without
>> using a tuner. Now if you had placed the feedpoint in the center you would
>> not have been able to get this consistency of feedpoint impedance from
>> band
>> to band. As I see it, this is a major reason for the popularity of the
>> end-fed approach as contrasted to the conventional center-fed approach.
>> Note
>> that the 30m coverage of the 80 meter and up design is not replicated if
>> you
>> try the same approach with half the wire length. In this case you will
>> need
>> a tuner to get reasonable swr on 30.
>>
>> An important consideration is antenna height. We all know that antennas
>> usually work better when placed higher. Looking a bit closer, we can look
>> beyond the general installation height and consider the height(s) of the
>> antenna part(s) that carry the most current. Antenna modelling may
>> calculate
>> the field as resulting from current levels in different individual pieces
>> of
>> the wire, and then it makes sense to elevate those portions more than
>> other
>> parts of the wire that carry less current. Another reason for this is the
>> effect of ground losses. Jim Brown, in his article that he just linked to,
>> shows that ground losses get worse the closer a vertical antenna is to
>> ground. This makes sense as currents in the lossy soil are caused by
>> induction from currents in the antenna. When we look at the current
>> distribution within the vertical antenna wire it again makes sense to
>> place
>> the part(s) of the wire with high current higher rather than lower. One of
>> the simplest portable antennas is a short wire or whip of a quarter wave
>> or
>> less. It will have a low feedpoint impedance that can probably be matched
>> reasonably without a tuner or with a limited-range tuner. However, with a
>> low impedance comes a current maximum at the feedpoint. This often means
>> close to the ground, so even with a good set of elevated radials,
>> considerable ground losses could be expected. (An actual connection to the
>> soil would generally be much worse, unless you bury a lot of wires.) With
>> a
>> longer wire (1/2 wavelengh at the lowest band) we can have a very high
>> feedpoint impedance, very low feedpoint current, and more elevated
>> location(s) of high curent portion(s) of 

[Elecraft] Re-Inventing the Tape Dipole

[Ken G Kopp]

http://www.eham.net/articles/5523/
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Re: [Elecraft] KX3

[Nr4c]

Are his filters centered?

A filter offset might cause him to tune off freq. 

Sent from my iPhone
...nr4c. bill


> On Nov 18, 2017, at 7:23 PM, Mike Harris  wrote:
> 
> Hi,
> 
> We have a visitor at another QTH. He is using a KX3. At present he seems to 
> have a problem.
> 
> If he transmits on 28511kHz I receive him on 28510kHz. When I transmit on 
> 28510kHz he receives me on 28511kHz.
> 
> The same applies when he is received on other radios so it's not my K3.
> 
> I have a copy of the manual, however, without being able to see or touch the 
> thing life is difficult. Similarly getting some sense out of the other op.
> 
> As far as I can tell the KX3 isn't in split, doesn't have any RIT/XIT.
> 
> Any other reason why this 1kHz offset should be happening.
> 
> Regards,
> 
> Mike VP8NO
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> Message delivered to n...@widomaker.com

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[Elecraft] KX3 Field Ant. for 80/40/30 Alternative to wire

[John Newgas]

I've used a narrow steel surveyor's tape as antenna.   You can get them quite 
cheaply on Amazon etc and they have  two advantages - they roll up very neatly 
and have the length of the antenna clearly written as you pull them out.  It is 
easy to solder little bit of flexible wire for connections onto where the 
buckle rivets on


G7LTQ - John N
From: Don Wilhelm 
Subject: Re: [Elecraft] KX3 Field Ant. for 80/40/30
Date: 18 November 2017 at 22:05:22 GMT
To: JT Croteau , elecraft@mailman.qth.net
Reply-To: donw...@embarqmail.com


The easiest end fed antenna for portable use with those bands on the KX2/KX3 
comes from some experiments and experience of one of the KX2 field testers (and 
an active SOTA ham).
Use a BNC to dual binding post (Pomona) adapter on the KX2/3.  Connect a 58 
foot piece of wire to the red (center conductor) post, and a 23 foot 
"counterpoise" wire to the black (shield) post.  The counterpoise wire can be 
run along the ground or laying on top of nearby bushes.
Tie a rock or other throwing item to the end of the 58 foot radiator and get it 
up in the air - TUNE it and operate.
No balun, no fuss, and the wire rolls up into a small ball for transport.





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Re: [Elecraft] P3 with SVGA

[Michael Eberle]

I use a "Y" adapter to power my P3 (no VGA) and W2 watt meter from the 
K3 12V output.  Before upgrading to the KXV3B, I used 2 "Y" adapters to 
power the 6M pre-amp as well and never had any problems.


Mike, KI0HA


On 11/19/2017 06:15, G4GNX wrote:

Hi Don.

Thanks for the info.

I performed the 1 Amp mod on my K3 myself, so I'm quite sure it's 1A 
capable and yes it does have the 1A label.


I'll look for a quality adapter. As they're normally meant for audio 
work, I was a little concerned that the internal wiring might only be 
intended to carry milliamps.


73,

Alan. G4GNX

-Original Message- From: Don Wilhelm
Sent: Sunday, November 19, 2017 12:04 PM
To: G4GNX ; Elecraft Reflector
Subject: Re: [Elecraft] P3 with SVGA

Alan,

Look at the label on your K3 12 volt output jack.  Does it say 0.5 amp
or does it say 1.0 amp?  The 12v change includes a sticker to re-label
the jack.

Yes, you could use a "Y" adapter, but use a good quality one so you
don't have a significant voltage drop due to loosely fitting connectors.

73,
Don W3FPR

On 11/19/2017 6:49 AM, G4GNX wrote:
I just assembled the P3 kit which includes the SVGA adaptor and the 
TX monitor.


In the original instructions, there’s a warning not to use the P3 
with SVGA adaptor, taking power from the K3’s 12 volt output. 
However, there’s a reference to the 1 Amp K3 modification in a later 
full manual for the P3, which says it’s OK to use the P3+SVGA, 
provided older K3s have the 1 Amp mod. 


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Re: [Elecraft] P3 with SVGA

[G4GNX]

Hi Don.

Thanks for the info.

I performed the 1 Amp mod on my K3 myself, so I'm quite sure it's 1A capable 
and yes it does have the 1A label.


I'll look for a quality adapter. As they're normally meant for audio work, I 
was a little concerned that the internal wiring might only be intended to 
carry milliamps.


73,

Alan. G4GNX

-Original Message- 
From: Don Wilhelm

Sent: Sunday, November 19, 2017 12:04 PM
To: G4GNX ; Elecraft Reflector
Subject: Re: [Elecraft] P3 with SVGA

Alan,

Look at the label on your K3 12 volt output jack.  Does it say 0.5 amp
or does it say 1.0 amp?  The 12v change includes a sticker to re-label
the jack.

Yes, you could use a "Y" adapter, but use a good quality one so you
don't have a significant voltage drop due to loosely fitting connectors.

73,
Don W3FPR

On 11/19/2017 6:49 AM, G4GNX wrote:
I just assembled the P3 kit which includes the SVGA adaptor and the TX 
monitor.


In the original instructions, there’s a warning not to use the P3 with 
SVGA adaptor, taking power from the K3’s 12 volt output. However, there’s 
a reference to the 1 Amp K3 modification in a later full manual for the 
P3, which says it’s OK to use the P3+SVGA, provided older K3s have the 1 
Amp mod. 


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Re: [Elecraft] P3 with SVGA

[Don Wilhelm]

Alan,

Look at the label on your K3 12 volt output jack.  Does it say 0.5 amp 
or does it say 1.0 amp?  The 12v change includes a sticker to re-label 
the jack.


Yes, you could use a "Y" adapter, but use a good quality one so you 
don't have a significant voltage drop due to loosely fitting connectors.


73,
Don W3FPR

On 11/19/2017 6:49 AM, G4GNX wrote:

I just assembled the P3 kit which includes the SVGA adaptor and the TX monitor.

In the original instructions, there’s a warning not to use the P3 with SVGA 
adaptor, taking power from the K3’s 12 volt output. However, there’s a 
reference to the 1 Amp K3 modification in a later full manual for the P3, which 
says it’s OK to use the P3+SVGA, provided older K3s have the 1 Amp mod.

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[Elecraft] P3 with SVGA

[G4GNX]

I just assembled the P3 kit which includes the SVGA adaptor and the TX monitor.

In the original instructions, there’s a warning not to use the P3 with SVGA 
adaptor, taking power from the K3’s 12 volt output. However, there’s a 
reference to the 1 Amp K3 modification in a later full manual for the P3, which 
says it’s OK to use the P3+SVGA, provided older K3s have the 1 Amp mod.

I’d prefer to use the power output from the K3, because it allows integrated 
switching of power to the P3. Am I correct in assuming that the later manual 
instructions are correct?

Also, I have the 6 metre (outboard) pre-amp which needs 12V power (very low 
current). As the K3 12V output is via an RCA (Phono) socket, has anyone used an 
RCA splitter to supply two devices?

73,

Alan. G4GNX

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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Igor Sokolov]

Very useful post Erik,

Thank you

73, Igor UA9CDC


19.11.2017 13:22, Erik Basilier пишет:

End-fed antennas have gotten popular lately. When I look closer I see two
different popular approaches.

The first uses a 9:1 impedance transformer in combination with a wire length
that is not resonant on any band. The idea is that (assuming there is no
significant feedline length) you have a medium impedance (450 ohms) on the
antenna side of the transformer, and because the wire is not resonant so you
might have an impedance into the wire that is also "medium". By adjusting
the wire length, you might get pretty close to 450 ohms on one or two bands,
and with a wide range tuner you can probably get below swr 2:1 for the radio
PA to see.

The second approach, used by MyAntennas and others seems to use a
transformer with much higher impedance ratio. One way to construct such a
transformer would be to cascade two 9:1 units for an effective ratio of
81:1. This would mean the wire should present an impedance of 4000 ohms or
so. Another way would be using a single tranformer with a higher ratio. The
impedance ratio is the square of the turns ratio. With a turns ratio of 9:1
you should again get to about 4000 ohms. Somewhere I saw somebody using an
8:1 turns ratio for an ideal antenna wire impedance of about 3200 ohms.
These impedance levels are achieved by using a resonant wire.

I don't know how you arrived at your parameters, but your wire length is too
close to resonance on 80 and 40. Your transformer ratio wants a non-resonant
wire, so you might see better results if you shorten the wire significantly
and keep using the KX3 ATU. Alternatively, you could replace the transformer
for a much higher impedance ratio, in which case you can probably operate
with the tuner bypassed at least on 80 and 40 with a well adjusted wire
length. With this approach you want the wire resonant on each band. It
should be easy to achieve resonance on 80, 40, 20 and 10. As you double the
frequency, you are changing the number of half wavelengths covered by the
wire; the end feedpoint is always at the end of one of these half
wavelengths, and thus you get the very high impedance that you seek. 30
meters does not fit as clearly into this scheme. The commercial versions use
a small coil in the wire located close to the transformer end, and seem to
be able to achieve a reasoable match for all the bands 80 and up without
using a tuner. Now if you had placed the feedpoint in the center you would
not have been able to get this consistency of feedpoint impedance from band
to band. As I see it, this is a major reason for the popularity of the
end-fed approach as contrasted to the conventional center-fed approach. Note
that the 30m coverage of the 80 meter and up design is not replicated if you
try the same approach with half the wire length. In this case you will need
a tuner to get reasonable swr on 30.

An important consideration is antenna height. We all know that antennas
usually work better when placed higher. Looking a bit closer, we can look
beyond the general installation height and consider the height(s) of the
antenna part(s) that carry the most current. Antenna modelling may calculate
the field as resulting from current levels in different individual pieces of
the wire, and then it makes sense to elevate those portions more than other
parts of the wire that carry less current. Another reason for this is the
effect of ground losses. Jim Brown, in his article that he just linked to,
shows that ground losses get worse the closer a vertical antenna is to
ground. This makes sense as currents in the lossy soil are caused by
induction from currents in the antenna. When we look at the current
distribution within the vertical antenna wire it again makes sense to place
the part(s) of the wire with high current higher rather than lower. One of
the simplest portable antennas is a short wire or whip of a quarter wave or
less. It will have a low feedpoint impedance that can probably be matched
reasonably without a tuner or with a limited-range tuner. However, with a
low impedance comes a current maximum at the feedpoint. This often means
close to the ground, so even with a good set of elevated radials,
considerable ground losses could be expected. (An actual connection to the
soil would generally be much worse, unless you bury a lot of wires.) With a
longer wire (1/2 wavelengh at the lowest band) we can have a very high
feedpoint impedance, very low feedpoint current, and more elevated
location(s) of high curent portion(s) of the antenna, for lower ground
losses.

Any antenna feed point needs to provide two terminals for the feed current
to flow through a complete circuit. A end-fed designed for medium to high
feed impedance has small feed current. In practice this means that whatever
is used as the counterpoise side can be small. The applies with a "medium
impedance" design as discussed earlier, but it applies even more for a
resonant end-fed with 

Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Richard Lamont]

On 18/11/17 05:43, Mark via Elecraft wrote:

> Re:  http://www.navy.mil/submit/display.asp?story_id=92864
> 
> So, "The rumors of my death have been greatly exaggerated"???

No, unfortunately for the CW evangelists, they haven't been.

The rumor that *is* being greatly exaggerated is that the US Navy is
'reverting to Morse' for its communications. There's no suggestion of
this in the press release cited.

What is happening is that the US Navy is *continuing* to train
*intercept operators* to read Morse. That is all. If you don't believe
me, read the press release.


73,
Richard G4DYA
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Re: [Elecraft] O.T. Morse is not dead, at least in the U.S. Navy

[Richard Lamont]

On 18/11/17 03:45, Ron D'Eau Claire wrote:

> http://www.navy.mil/submit/display.asp?story_id=92864

The people being trained by the US Navy to read Morse are intercept
operators.

"Morse code is just one tool that cryptologic technician (collection)
Sailors use as members of the Navy's Information Warfare community to
perform collection, analysis and reporting on communication signals."

There's nothing in this press release to suggest that the US Navy is
reverting to Morse for two-way communication.

73,
Richard G4DYA
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Re: [Elecraft] KX3 Field Ant. for 80/40/30

[Erik Basilier]

End-fed antennas have gotten popular lately. When I look closer I see two
different popular approaches. 

The first uses a 9:1 impedance transformer in combination with a wire length
that is not resonant on any band. The idea is that (assuming there is no
significant feedline length) you have a medium impedance (450 ohms) on the
antenna side of the transformer, and because the wire is not resonant so you
might have an impedance into the wire that is also "medium". By adjusting
the wire length, you might get pretty close to 450 ohms on one or two bands,
and with a wide range tuner you can probably get below swr 2:1 for the radio
PA to see.

The second approach, used by MyAntennas and others seems to use a
transformer with much higher impedance ratio. One way to construct such a
transformer would be to cascade two 9:1 units for an effective ratio of
81:1. This would mean the wire should present an impedance of 4000 ohms or
so. Another way would be using a single tranformer with a higher ratio. The
impedance ratio is the square of the turns ratio. With a turns ratio of 9:1
you should again get to about 4000 ohms. Somewhere I saw somebody using an
8:1 turns ratio for an ideal antenna wire impedance of about 3200 ohms.
These impedance levels are achieved by using a resonant wire.

I don't know how you arrived at your parameters, but your wire length is too
close to resonance on 80 and 40. Your transformer ratio wants a non-resonant
wire, so you might see better results if you shorten the wire significantly
and keep using the KX3 ATU. Alternatively, you could replace the transformer
for a much higher impedance ratio, in which case you can probably operate
with the tuner bypassed at least on 80 and 40 with a well adjusted wire
length. With this approach you want the wire resonant on each band. It
should be easy to achieve resonance on 80, 40, 20 and 10. As you double the
frequency, you are changing the number of half wavelengths covered by the
wire; the end feedpoint is always at the end of one of these half
wavelengths, and thus you get the very high impedance that you seek. 30
meters does not fit as clearly into this scheme. The commercial versions use
a small coil in the wire located close to the transformer end, and seem to
be able to achieve a reasoable match for all the bands 80 and up without
using a tuner. Now if you had placed the feedpoint in the center you would
not have been able to get this consistency of feedpoint impedance from band
to band. As I see it, this is a major reason for the popularity of the
end-fed approach as contrasted to the conventional center-fed approach. Note
that the 30m coverage of the 80 meter and up design is not replicated if you
try the same approach with half the wire length. In this case you will need
a tuner to get reasonable swr on 30. 

An important consideration is antenna height. We all know that antennas
usually work better when placed higher. Looking a bit closer, we can look
beyond the general installation height and consider the height(s) of the
antenna part(s) that carry the most current. Antenna modelling may calculate
the field as resulting from current levels in different individual pieces of
the wire, and then it makes sense to elevate those portions more than other
parts of the wire that carry less current. Another reason for this is the
effect of ground losses. Jim Brown, in his article that he just linked to,
shows that ground losses get worse the closer a vertical antenna is to
ground. This makes sense as currents in the lossy soil are caused by
induction from currents in the antenna. When we look at the current
distribution within the vertical antenna wire it again makes sense to place
the part(s) of the wire with high current higher rather than lower. One of
the simplest portable antennas is a short wire or whip of a quarter wave or
less. It will have a low feedpoint impedance that can probably be matched
reasonably without a tuner or with a limited-range tuner. However, with a
low impedance comes a current maximum at the feedpoint. This often means
close to the ground, so even with a good set of elevated radials,
considerable ground losses could be expected. (An actual connection to the
soil would generally be much worse, unless you bury a lot of wires.) With a
longer wire (1/2 wavelengh at the lowest band) we can have a very high
feedpoint impedance, very low feedpoint current, and more elevated
location(s) of high curent portion(s) of the antenna, for lower ground
losses. 

Any antenna feed point needs to provide two terminals for the feed current
to flow through a complete circuit. A end-fed designed for medium to high
feed impedance has small feed current. In practice this means that whatever
is used as the counterpoise side can be small. The applies with a "medium
impedance" design as discussed earlier, but it applies even more for a
resonant end-fed with its tiny feed current. A short piece of wire may be
used, but often not even that is