Don, the K3 seem to not like a bug.

With my K3S i use always a bug (a Vibroplex Presentation or a Begali Intrepid).

In the past, when keying with the bug, the K3 displey become blank and sometime appeared on the K3S display, diagnostic  that disappeared when I used my paddle with the internal keyer. 

Even with HI CURR the transceiver transmitted well. 

With a firmware upgrade this problem was solved and I hadnt this strange problem, us since when last month I installed the last firmware 5.66.

Now, only on 20m it seem to me, when transmitting with 100w HI CURR appear and the transceiver reduce the power to 85 watts.

I signaled it to Elecraft, at first they thought it was a power supply low voltage on transmission, but when I said that i see the problem only on 20m, with 1.5 SWR, that it disappear when using ATU, they said me to reinstall 5.64 firmware and try again to see if there is the problem.

In the past I thought that K3S (and K3 as it seem) doesnt like the bug little bounces (or scratch dots...), on the keying input.

I send you below my exchange with Elecraft support  in  2016 that can evidence better the past problems. I hope it help you.

For the actual problem of HI CURR diagnostic on 20m, I am thinking to reinstall the 5.64 firmware version. With it I havent problems even without ATU inserted.

What is your firmware version? do you have 5.66?

73,

Ian IK4EWX

Da: Gian Luca Cazzola <glcazzola@...>

Oggetto: Re: IK4EWX: K3S losing swr-watt meters indications on tx - please help

Data: 29 giugno 2016 00:05:04 CEST

A: k3support@...

Cc: Carlo Bianconi <carlobianconi@...>

Sorry Dave, I have seen only today that your elecraft server haven’t received my reply.

So I repeat here.

-MY K3S HAVE SERIAL NUMBER 10715

-I SEE THE PROBLEM AT ALL POWER LEVELS, REDUCING AT 80 -60-40W DOESNT SOLVE. I AM NOT SURE ABOUT 20 W.

WITH THE ATU INSERTED IT HAPPEN LESS FREQUENTLY.

- THERE ARENT DIFFERENCEs IN WATTS OR SWR REaD ON K3S OR MY BIRD 43.

BUT WHEN THE SWR AND RF INDICATIONS ON K3S DISPLAY GONE BLANK, WHEN I MAKE  WITH  A LITTLE TUNE WITH THE BUG  DASH CONTACTS, OR  

EVEN SENDING NORMAL MESSAGES, DOTS AND DASHES KEYING WITH MY BUG, THE POWER ON THE BIRD 43  READ NORMAL WATTS, THOSE  CHOICED ON THE K3S

(EXAMPLE WITH POWER 90W CHOICED WITH THE K3S POT, AND KEYING WITH THE BUG, THE SWR AND RF DISPLAY GO BLANK - I READ THE SWR AND RF LETTERS 

BUT NO PIXELS OVER THEM - BUT ON THE BIRD 43 I SEE THE NORMAL 90 W OUTPUT).

I HAVENT OPTED THE QRQ NEW COMMAND ON THE CONFIG - SO IT ISN’T THE PROBLEM, WITH MY BUG ADJUSTED AT 18-25WPM

I have understood from your mail that the key input  is well filtered and  also debounced, but I have this problem, that also other hams on the K3 forum say to have.

You have read them.

Can you make something?

Mi friend Carlo Bianconi say that the rig have no electronic problems.

So do you know what can be the problem? Firmware?

Thanks es 73

Ian IK4EWX

Il giorno 20 giu 2016, alle ore 20:36, David Shoaf < k3support@...> ha scritto:

Hi Ian,

Thanks for the contact.  To your questions, we do not believe that adding additional components will affect the problem.

As shown on the K3S schematic, there are RF chokes and capacitors bypassing all the inputs on the K3S so additional ones outside the K3S would not be adding anything.

<lncmegamcpmiohfj.png>

We are also CC'ing our Authorized Warranty Repair Center, who may also be able to help.  

Additional questions:

- What is the serial number of your K3S?

- Do you see the problem at lower power levels (20, 40, 60 watts)?  Does it do the same thing on the dummy load?

- When you see the RF on the Bird 43, what do you see on the K3S display for RF and SWR?  Do they agree or not?

Cheers,

David

---------------------------------------
David Shoaf/KG6IRW
Elecraft International Distributor and Customer Support
831-763-4211 x121
---------------------------------------

On 6/20/2016 8:55 AM, glcazzola@... wrote: 

Yesterday I wrote on Elecraft K3 email list:

I own a great K3S from a pair of months. It work great, dx, qsos, contest (just worked CQWPX, 1200 qsos).  
Just after bought it, sometime on cw transmission  the swr-rf indications, the moving black dots, gone all blanked, all on the swr and on RF indications.  
I thought about rfi problems, but it happened even with dummy load. And with no swr on antenna.  
With atu inserted is seemed more rarely happen.  
This morning I have this problem happen at least on 14-18-21-24-28mhz, keying the rig with my bug, only with long dash and not with dots string.  
It is a rainy cloudy day, but I think that doesnt matter :)  
When using the paddle with internal keyer I havent the problem.  
It seem to happen only when keying is at least 2-3 seconds long.  
When it happen, with the two measurements blanked, the rig really continue to transmit - I see regular power on my external Bird 43 wattmeter.  
Somebody had this problem and know how to solve it?  
Many thanks  
Ian IK4EWX 

I received this reply from Lucien W5QD:

Yes, both my K3 and a K3s do this when I key them with my bugs or with my 
straight key. Even my K2's will behave strangely, though not quite as 
bad as 
the K3 and s. It's not a problem with the rig; it's just a contact 
bounce 
issue, so you'll just need a debouncing circuit. Either an external 
keyer 
(most of them have debouncing circuitry in them) or you can home-brew one. 
There are a couple good circuits in the list archives. 

A capacitor across the bug terminals will help, say a .1 uf, but beware that 
it'll key the rig momentarily when you first plug it in as the cap 
charges. 

73, LS -  W5QD 

I can say only that I am astonhished. 

It seem impossible that  rig of the K3S quality and price have this incredible ridicoulous problem.

Is it true and should I make a home made modification of the kind suggested?

Thanks

Gian Luca Cazzola - IK4EWX

----Messaggio originale----
Da: wb6bee@...
Data: 14-gen-2019 14.50
A: <Elecraft-K3@groups.io>
Ogg: [Elecraft-K3] Using a Bug key with the K3s

I have had three instances of unexplained events, using a Bug key with the K3s.   I am 100 % cw and only use a bug.   My speed is about 26-27 wpm on the key.   

1.  Event one:   I added the TXMON to the P3 to see if I could use it for evaluating keying, hoping it would show things like scratchy dots, etc.   It didn't show much at all, actually.   What was odd was the with some regularity, but no consistency, the display would go from the keying envelope to a line of static, similar looking to band noise on a spectrum analyzer.   A friend of mine, also using a Bug with the TXMON, was experiencing a similar situation.   I reported it to Elecraft Tech. They sent me, one component at a time, a new TXMON.   Nothing changed, the unit continued to have the erratic display.   Being somewhat useless, I put the TXMON in the box of unused parts.   Elecraft tech never followed up with the issue, probably not that many bug users with the TXMON.

2. Event Two:  Noted in this relfector some weeks ago.   Minor frequency shifts ( a few hertz) while keying with a bug.   

3. Event Three:   I have a new KPA 1500.   Twice now, when in a long transmission, the amp will kick out.   No apparent reason, but my keying in the CW monitor would sound like something was wrong with the bug, loose weight or something.   Then, the amp would be in a fault condition.   In both cases, the fault log would show an overdrive condition.  My normal drive for the KPA from the K3s is about 30 watts or so (depending).   The default log showed drive at over 65 watts.   The first time it happened, I thought perhaps I hit something on the front of the K3s.   The second time, no such possibility (probably  not the first time either).   The first time was 160 meters.  The second time was 80 meters.   A common denominator is the 68 ft vertical antenna used for both bands.  

These could all be related, or they could not.   Elecraft tech indicated they were going to try to use a bug to replicate the last event.   It is so irregular that I don't that would work.     However, K3s are so popular, maybe other owners have had issues with using a bug with the K3s

Don
WB6BEE