[Elecraft] One of my most-used K3/K3S/KX3/KX2 features: Per-band quick memories

[Wayne Burdick]

All of our K-Line and KX-Line rigs include our "quick memories" feature. I use 
this all the time. In case you missed it, I thought I'd remind everyone how it 
works.

First: Why do you need quick memories? The general idea is that, on each band, 
you probably have some favorite starting points (frequencies) in each mode, or 
maybe a couple of them in a particular mode. For example, on 20 meters I 
typically start looking for signals on 14005 in CW mode, 14200 in SSB mode, 
140083 in FSK-D (RTTY) mode, etc. On 6 and 10 meters I use only CW and SSB, but 
I have a couple of favorite beacons. On transverter bands, I have some local 
repeaters I routinely check.

The need for these often-used starting points is what led us to the 
quick-memory concept. You can store and recall up to 4 quick memories on each 
band.

Here's how it works:

1. Set up a VFO frequency and mode of interest. (Set up both VFO A and B if you 
like. I always do this, in effect making each quick memory store two 
frequencies that I can quickly check by tapping A/B. In some cases I use them 
as the starting and ending points for scanning.)

2. Tap V>M (on the K3/K3S) or STORE (on the KX3/KX2). 

3. Tap the '1' switch on the numeric keypad. This saves the present VFOs to the 
first quick memory.

Repeat these steps to create up to four quick memories on the current band, 
then move to the next band.

To retrieve a quick memory, tap M>V (K3/K3S) or RCL (KX3/KX2).

73,
Wayne
N6KR



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

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

Re: [Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode

[Mike K8CN]

Thanks, Keith, for the pointer on audio IC U1 on the DSP board.  Visual
inspection shows no obvious sign of overheating on the IC or the DSP board
itself.  Will have to find a thermometer with a fine tip probe to measure
surface temperature on U1 though - household thermometers I have are too
large to fit into that space.

73,
Mike, K8CN



--
Sent from: http://elecraft.365791.n2.nabble.com/
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

[Elecraft] FS: Like new K3S/100

[Ken Arck]

K3S/100 with current firmware. In like new condition - no scrapes, 
scratches, etc.


K144XV-K 2 meter internal transverter
K144RFLKV Reference Lock

Basic filters as received from Elecraft

No tuner but custom board that allows selection of ANT1/ANT2 from 
front panel button.


$2,700, shipped CONUS firm
--
President and CTO - Arcom Communications
Makers of repeater controllers and accessories.
http://www.arcomcontrollers.com/
Authorized Dealers for Kenwood and Telewave and
we offer complete repeater packages!
AH6LE/R - IRLP Node 3000
http://www.irlp.net
"We don't just make 'em. We use 'em!"

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

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

Re: [Elecraft] K2: I killed my KPA100

[Jim KO5V]

Hi Don,

I got the following results:

1. Base K2 seems to be OK.

2. The KPA100 is upside down next to the K2, and everything is powered through 
the K2 and its power supply. Using the LP-100 and 50ohm dummy load, the 5W and 
10W measurements through the KPA100 check out nominally.

3. When I apply power through the KPA100's power port, and using its power 
supply, the K2 and KPA100 are dead. The power supply measures about 1.8V when 
plugged into the KPA100, but ~13.5V with no load. 

4. As I mentioned below, I previously checked D9 and D10 and Q5. D10 and Q5 
were OK, but I didn't really understand what I saw when I checked D9. From my 
first post:

"I lifted one side of D10, and it seems to test OK, but when I did the same to 
D9, it looked weird - In "diode" mode, I get .150V in one direction, open in 
the other. When I test it in resistance, I eventually measure 80-90ohms in one 
direction (it takes a moment to settle), but it's open in the other. It might 
be OK?"

Next?

Thanks. 73,

Jim KO5V


-Original Message-
>From: Don Wilhelm 
>Sent: Feb 3, 2019 8:50 PM
>To: Jim KO5V , Elecraft List 
>Subject: Re: [Elecraft] K2: I killed my KPA100
>
>Jim,
>
>My usual procedure when tackling a problem of that nature is to first 
>isolate the problem to one component.
>You have already apparently checked out the base K2.
>
>Next, remove the top cover from the base K2 and connect the KPA100 to it 
>(remove the KPA100 from the EC2 enclosure).
>Put the KPA100 upside down on a box or book about 1/2 the height of the 
>K2 and plug the cables into the K2.
>
>Then test with an external wattmeter and a dummy load connected to the 
>KPA100 SO-239 antenna jack.
>
>First power the base K2 from the 2.1mm coaxial power jack.  Check at 5 
>watts and at 10 watts - this checks the transmit path through the KPA100 
>in QRP mode.  Use an external wattmeter and a dummy load.  Does the 
>external wattmeter agree roughly with the K2 display indication and the 
>power knob setting.
>
>If you have a much higher actual power level on the external wattmeter, 
>the KPA100 wattmeter diodes D16 and D17 are the first suspects - replace 
>them.
>
>If all is well so far, remove the 2.1mm power plug and power the 
>assembly with the APP connector on the KPA100.  Make the same test.
>
>After that, check the bias on the KPA100 for a 400ma rise in current 
>with the K2 set to CW and in CW TEST mode.  Hold the mode button until 
>TEST appears in the LCD, and the CW icon will blink.
>
>Do a tune and check that the current rise from receive to TUNE is 400ma.
>
>Then set the power to 50 watts and do a TUNE.  Read the actual power on 
>the external wattmeter.  With a TUNE, it should be about 20 watts.
>
>If it is greater, you have a problem with the KPA100 wattmeter - likely 
>diodes D16 and D17 have been damaged and need to be replaced.
>
>More troubleshooting is possible, but that is a good starting point.
>If all goes well with those tests, then I can tell you how to check the 
>KAT100 alone (without the KPA100).
>
>73,
>Don W3FPR
>
>On 2/3/2019 10:13 PM, Jim KO5V wrote:

>> Earlier today, I had been trying to get my computer to talk to the K2 
>> through a logging program. After I built the rig, I tested my cables and the 
>> KIO2 by successfully controlling the K2 with 'K2 Remote', so it was working. 
>> Today, the logging software would poll the K2, and get no response. 'K2 
>> Remote" couldn't see the rig either. The DB9 connector that connects to the 
>> KIO2 has the cables to the KPA/KAT and serial cable, and I made sure the 
>> computer's connector was wired correctly for interfacing a "normal" serial 
>> cable to the KIO2. It all worked.
>> 
>> I looked at the KPA schematic, and thought a diode, or something in the 
>> current sensing circuit might have failed. I removed Q5, and it tests just 
>> like my new spare. I lifted one side of D10, and it seems to test OK, but 
>> when I did the same to D9, it looked weird - but I don't really understand 
>> that device; In "diode" mode, I get .150V in one direction, open in the 
>> other. When I test it in resistance, I eventually measure 80-90ohms in one 
>> direction (it takes a moment to settle), but it's open in the other. It 
>> might be OK? I hope I didn't kill U7.
>> 
>> I performed the resistance tests in the KPA manual, and they are nominal. Q1 
>> and Q2 test OK, and I think Q3 and Q4 are OK. Q3 tests differently than Q4, 
>> but looking at the schematic, I think what I see makes sense.
>> 
>> It also occurred to me that when I was trying to get the logging program to 
>> work, I might have caused a failure in my cables while I was hooking and 
>> unhooking the serial connection. That might have caused a communication 
>> problem that made the amp go a bit nuts.
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

Th

Re: [Elecraft] KPA1500 ATU

[N4ZR]

I'm seeing a similar phenomenon, Scott, but figured I'm too much of a 
newbie with the amp to question it.


73, Pete N4ZR
Check out the Reverse Beacon Network
at , now
spotting RTTY activity worldwide.
For spots, please use your favorite
"retail" DX cluster.

On 2/6/2019 10:49 AM, K9MA wrote:
Ever since I received my KPA1500 (SN 00178), I've observed that the 
ATU sometimes won't achieve a match better than about 1.4:1, even 
though the antenna SWR is well within range. (ATU STOP TUN SWR = 
1.0:1, tune power 40 W) Now, 1.4:1 doesn't sound that high, but the 
amplifier will often not operate at full output at that SWR, either 
due to excessive current or drive power. This is particularly 
troublesome when tuning across a band. Clearly, the KPA1500 is 
designed to deliver 1500 W to a 50 Ohm load, with little margin for a 
mismatch. More margin would have increased cost, size, and weight, of 
course.


Just to be sure there isn't something unique wrong with my KPA1500, 
have others observed similar behavior?


A little ice on the antenna this morning provided an opportunity for a 
test. On 40 meters, the antenna SWR was 2.2:1. The best match the 
KPA1500 ATU could attain automatically was 1.4:1, in multiple 
attempts. I was able to manually get it down to 1.1:1. (SWR as 
indicated by the KPA1500 display.) It was a little tricky, requiring 
one value to be increased beyond the SWR minimum before the other was 
adjusted, as often happens with manual tuners. With the KPA1500 ATU 
bypassed, the K3 ATU automatically got it down to 1:1 on the first try.


My conclusion is that there's something about the KPA1500 ATU 
algorithm that prevents it from achieving a better match, in some 
cases. (I'm assuming that, aside from their power ratings, the 
components in the KPA1500 ATU and the K3 ATU are similar.)  I'm 
wondering if the KPA1500 ATU algorithm could be improved to perform 
more like that of the K3 ATU. That would allow operating the KPA1500 
closer to full power across a band without having to ride the power 
control.


Further details of ATU component values, etc. are available.

73,

Scott K9MA



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

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

Re: [Elecraft] Running KPA500 on generators.

[Dennis Moore]

Quite a few DXpeditions have run in the past few years with KPA500s and 
Honda generators. I think you'll be fine.


73, Dennis NJ6G

On 2/6/2019 07:53, Neil Ramhorst wrote:

  I’m gearing up for grid squares this summer. I’m thinking of purchasing a
KPA 500 amplifier. Does anyone have experience running one of them on the
dual configuration of Honda EU 2000 generator‘s?
Neil

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

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

Re: [Elecraft] Running KPA500 on generators.

[Fred Jensen]

When we were still doing CQP [Alpine County] from Camp FYNO at 8,500 ft, 
we had a Honda 2000i.  Outside the contest, it idled all night powering 
the electric blankets. During the contest, it would not tolerate either 
CW or SSB in that mode.


73,
Fred ["Skip"] K6DGW
Sparks NV DM09dn
Washoe County

On 2/6/2019 11:13 AM, Jim Brown wrote:

On 2/6/2019 8:04 AM, David Bunte wrote:

N9FN and I have run several state QSO parties with a K3, computer and
KPA500 from a single Honda EU2000i


Same for our group working CQP and 7QP. A single 2000i works great to 
run a single K3/KPA500 station. We use Thinkpads for logging. W6GJB 
bought the device to sync two 2000i generators, and we use that setup 
to run two K3/KPA500 stations. We run 120V.


73, Jim K9YC


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

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

Re: [Elecraft] Running KPA500 on generators.

[Jim Brown]

On 2/6/2019 8:04 AM, David Bunte wrote:

N9FN and I have run several state QSO parties with a K3, computer and
KPA500 from a single Honda EU2000i


Same for our group working CQP and 7QP. A single 2000i works great to 
run a single K3/KPA500 station. We use Thinkpads for logging. W6GJB 
bought the device to sync two 2000i generators, and we use that setup to 
run two K3/KPA500 stations. We run 120V.


73, Jim K9YC

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

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

Re: [Elecraft] Running KPA500 on generators.

[K8TE]

GM Neil,

I regularly use my KPA500 on a generator.  This week, I'm using it on a
Cummins 3.5 KW in our RV.  One year ago, I used it on a Harbor Freight
Predator equivalent to the Honda 2 KW inverter.  It works well on all three.

The only caveat is when operating CW, I needed to avoid using the "Econ"
mode which sets the idle speed much lower.  The Honda and HF versions didn't
like the sudden change in current draw and would fault.  As always, check
the HV supply reading on the KPA500 to determine if a different transformer
primary setting is necessary under load.

I want to add the KPA500 manual describes the different primary tap
settings.  There seems to be a lack of manual-checking going around these
days.  The updated manuals (firmware changes) are invaluable tools! 
Fortunately, Elecraft allows making notes in the PDF versions of their
manuals (copy and paste) which is much easier to accomplish than in the
printed versions.

73, Bill, K8TE



--
Sent from: http://elecraft.365791.n2.nabble.com/
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

Re: [Elecraft] [K3] Spontaneous HI CURR, audio reduction in RX mode

[Keith Trinity WE6R]

Hi Mike;
Can you go to config menu item "FW REVS" an tell me what you see please?

If you are still getting the HI CUR warning, the U1 audio chip on the 
DSP board may have partly failed and will be getting HOT!
It can heat enough to MELT the DSP board and cause an internal short 
that destroys the whole board!
If you can catch it before that happens, you will save a lot of money 
and grief.
If you take the top cover off, and the upper left area of the front 
panel, directly behind the BAND up and down buttons, is the audio chip 
on the DSP board.
It is a black cube about 1/2 square at the top corner of that board. 
Stick a thermometer down there.

Keith WE6R
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

Re: [Elecraft] KPA1500 ATU

[K9MA]

Hi Ken,

At the frequency of interest, the KPA1500 ATU goes right to bypass mode 
with a dummy load.


73,
Scott K9MA



On 2/6/2019 10:06, wa2...@gmail.com wrote:

Scott,

Did you try testing with a 50 ohm dummy load instead of an antenna?  
How goes it react?



/Ken /
/WA2LBI /
/LG G6 /
/
/

-- Original message--
*From: *K9MA
*Date: *Wed, Feb 6, 2019 10:50
*To: *elecraft@mailman.qth.net ;
*Cc: *
*Subject:*[Elecraft] KPA1500 ATU

Ever since I received my KPA1500 (SN 00178), I've observed that the ATU
sometimes won't achieve a match better than about 1.4:1, even though the
antenna SWR is well within range. (ATU STOP TUN SWR = 1.0:1, tune power
40 W) Now, 1.4:1 doesn't sound that high, but the amplifier will often
not operate at full output at that SWR, either due to excessive current
or drive power. This is particularly troublesome when tuning across a
band. Clearly, the KPA1500 is designed to deliver 1500 W to a 50 Ohm
load, with little margin for a mismatch. More margin would have
increased cost, size, and weight, of course.

Just to be sure there isn't something unique wrong with my KPA1500, have
others observed similar behavior?

A little ice on the antenna this morning provided an opportunity for a
test. On 40 meters, the antenna SWR was 2.2:1. The best match the
KPA1500 ATU could attain automatically was 1.4:1, in multiple attempts.
I was able to manually get it down to 1.1:1. (SWR as indicated by the
KPA1500 display.) It was a little tricky, requiring one value to be
increased beyond the SWR minimum before the other was adjusted, as often
happens with manual tuners. With the KPA1500 ATU bypassed, the K3 ATU
automatically got it down to 1:1 on the first try.

My conclusion is that there's something about the KPA1500 ATU algorithm
that prevents it from achieving a better match, in some cases. (I'm
assuming that, aside from their power ratings, the components in the
KPA1500 ATU and the K3 ATU are similar.)  I'm wondering if the KPA1500
ATU algorithm could be improved to perform more like that of the K3 ATU.
That would allow operating the KPA1500 closer to full power across a
band without having to ride the power control.

Further details of ATU component values, etc. are available.

73,

Scott K9MA

--
Scott  K9MA
k...@sdellington.us  

_



--
Scott  K9MA

k...@sdellington.us

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

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

Re: [Elecraft] KPA1500 ATU

[wa2...@gmail.com]

Scott,
Did you try testing with a 50 ohm dummy load instead of an antenna?  How goes 
it react?

Ken WA2LBI LG G6 

-- Original message--From: K9MADate: Wed, Feb 6, 2019 10:50To: 
elecraft@mailman.qth.net;Cc: Subject:[Elecraft] KPA1500 ATU
Ever since I received my KPA1500 (SN 00178), I've observed that the ATU 
sometimes won't achieve a match better than about 1.4:1, even though the 
antenna SWR is well within range. (ATU STOP TUN SWR = 1.0:1, tune power 
40 W) Now, 1.4:1 doesn't sound that high, but the amplifier will often 
not operate at full output at that SWR, either due to excessive current 
or drive power. This is particularly troublesome when tuning across a 
band. Clearly, the KPA1500 is designed to deliver 1500 W to a 50 Ohm 
load, with little margin for a mismatch. More margin would have 
increased cost, size, and weight, of course.

Just to be sure there isn't something unique wrong with my KPA1500, have 
others observed similar behavior?

A little ice on the antenna this morning provided an opportunity for a 
test. On 40 meters, the antenna SWR was 2.2:1. The best match the 
KPA1500 ATU could attain automatically was 1.4:1, in multiple attempts. 
I was able to manually get it down to 1.1:1. (SWR as indicated by the 
KPA1500 display.) It was a little tricky, requiring one value to be 
increased beyond the SWR minimum before the other was adjusted, as often 
happens with manual tuners. With the KPA1500 ATU bypassed, the K3 ATU 
automatically got it down to 1:1 on the first try.

My conclusion is that there's something about the KPA1500 ATU algorithm 
that prevents it from achieving a better match, in some cases. (I'm 
assuming that, aside from their power ratings, the components in the 
KPA1500 ATU and the K3 ATU are similar.)  I'm wondering if the KPA1500 
ATU algorithm could be improved to perform more like that of the K3 ATU. 
That would allow operating the KPA1500 closer to full power across a 
band without having to ride the power control.

Further details of ATU component values, etc. are available.

73,

Scott K9MA

-- 
Scott  K9MA

k...@sdellington.us

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

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

Re: [Elecraft] Running KPA500 on generators.

[David Bunte]

Neil -

N9FN and I have run several state QSO parties with a K3, computer and
KPA500 from a single Honda EU2000i

Awesome performance

Dave - K9FN

On Wed, Feb 6, 2019 at 10:57 AM Neil Ramhorst  wrote:

>  I’m gearing up for grid squares this summer. I’m thinking of purchasing a
> KPA 500 amplifier. Does anyone have experience running one of them on the
> dual configuration of Honda EU 2000 generator‘s?
> Neil
> --
> Neil Ramhorst KL7JGS
> P.O. Box 4424
> Bozeman, MT 59772-4424
> 406-581-1575
> __
> 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 dpbu...@gmail.com
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

Re: [Elecraft] Tx distortion

[mustang65]

Don,

Thanks for advice.
Have checked with to different powersupplies one is a icom ps15 with new
caps. and the other is a 
homemade unit both is linear with transformer.

The voltage looks stable on k2 display with 13,8 from Icom and 14,2 from the
other.

Looking with the scope  I see 120mv ripple with Icom and 80 mv with the
other
on voicepeaks and ssb tx.

I have replaced c16 and c13  on the controlboard with no inprovment.

73 Mike sm3xgm





--
Sent from: http://elecraft.365791.n2.nabble.com/
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

[Elecraft] Running KPA500 on generators.

[Neil Ramhorst]

 I’m gearing up for grid squares this summer. I’m thinking of purchasing a
KPA 500 amplifier. Does anyone have experience running one of them on the
dual configuration of Honda EU 2000 generator‘s?
Neil
-- 
Neil Ramhorst KL7JGS
P.O. Box 4424
Bozeman, MT 59772-4424
406-581-1575
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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

[Elecraft] KPA1500 ATU

[K9MA]

Ever since I received my KPA1500 (SN 00178), I've observed that the ATU 
sometimes won't achieve a match better than about 1.4:1, even though the 
antenna SWR is well within range. (ATU STOP TUN SWR = 1.0:1, tune power 
40 W) Now, 1.4:1 doesn't sound that high, but the amplifier will often 
not operate at full output at that SWR, either due to excessive current 
or drive power. This is particularly troublesome when tuning across a 
band. Clearly, the KPA1500 is designed to deliver 1500 W to a 50 Ohm 
load, with little margin for a mismatch. More margin would have 
increased cost, size, and weight, of course.


Just to be sure there isn't something unique wrong with my KPA1500, have 
others observed similar behavior?


A little ice on the antenna this morning provided an opportunity for a 
test. On 40 meters, the antenna SWR was 2.2:1. The best match the 
KPA1500 ATU could attain automatically was 1.4:1, in multiple attempts. 
I was able to manually get it down to 1.1:1. (SWR as indicated by the 
KPA1500 display.) It was a little tricky, requiring one value to be 
increased beyond the SWR minimum before the other was adjusted, as often 
happens with manual tuners. With the KPA1500 ATU bypassed, the K3 ATU 
automatically got it down to 1:1 on the first try.


My conclusion is that there's something about the KPA1500 ATU algorithm 
that prevents it from achieving a better match, in some cases. (I'm 
assuming that, aside from their power ratings, the components in the 
KPA1500 ATU and the K3 ATU are similar.)  I'm wondering if the KPA1500 
ATU algorithm could be improved to perform more like that of the K3 ATU. 
That would allow operating the KPA1500 closer to full power across a 
band without having to ride the power control.


Further details of ATU component values, etc. are available.

73,

Scott K9MA


--
Scott  K9MA

k...@sdellington.us

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

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

Re: [Elecraft] KX3 issue

[Grant Youngman]

Do you have mic bias turned on?


Grant NQ5T
K3 #2091 KX3 #8342

> On Feb 6, 2019, at 7:37 AM,   wrote:
> 
> Yesterday I tried to use it on 10M SSB and was getting no audio indication on 
> the level meter. Tried it on AM and FM with same results. When I got home I 
> tried the MH3 Mic on my KX2 and it worked perfectly.
> I glanced through my "quick reference" ( it didn't come with the manual when 
> I bought it" and didnt see anything obvious about turning the audio on or off.
> Any ideas fellers?

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

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

[Elecraft] KX3 issue

[w5sum]

I have a KX3 issue and I hope you folks can help me. I purchased my KX-3 used 
last year. It came with all the good stuff including 2 meters. I used it to 
check into the local 2 meter repeater several times last year but have not used 
it for any voice modes since. I am a CW guy.
Yesterday I tried to use it on 10M SSB and was getting no audio indication on 
the level meter. Tried it on AM and FM with same results. When I got home I 
tried the MH3 Mic on my KX2 and it worked perfectly.
I glanced through my "quick reference" ( it didn't come with the manual when I 
bought it" and didnt see anything obvious about turning the audio on or off.
Any ideas fellers?


Ronnie W5SUM
__
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

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