[Elecraft] K3 transmit audio cuts out

Fri Jul 27 19:02:51 EDT 2012

Keith, OK on that. I have had a similar experience;

Clamp ferrites on the mic line are beneficial, about 6 or so(wrap the core
as much as possible, allowing to shut).

# A series rf choke and 0.1uF bypass(to gnd) at the amp end keyline is
beneficial also.
Clamp ferrites also on the keyline help if you don't wish to do #.

Choking the coaxial feed at the SteppIR feedpoint, and again at shack entry
is helpful, if not already done.

-----Original Message-----
From: Keith Heimbold [mailto:ag6az at hotmail.com]
Sent: Saturday, 28 July 2012 8:23 AM
To: Adrian
Cc: Elecraft Group
Subject: Re: [Elecraft] K3 transmit audio cuts out

Adrian,

I am looking at this as an rfi issue first and foremost. I am going to clean
up a little bit inside the shack. That particular K3 has been suffering with
unusual noise with my new SteppIR three element that was put up less than a
month ago. 

To answer your question, the K3 was in transmit mode the entire time when
the audio was cutting out. Very odd.

If it turns out to be not a rfi issue then I will investigate the K3 a
little more. I am shipping my other K3 to Elecraft tomorrow for a couple key
mods and upgrades (negative ALC and band control which is important to me
for a possible future KPA500 purchase) and it will be out of pocket for
three or so weeks so I want to make sure that it is good to go.

Thanks,

Keith
AG6AZ

Sent from my iPhone please excuse typos

On Jul 27, 2012, at 1:16 PM, "Adrian" <vk4tux at bigpond.com> wrote:

> Keith, From your original post you seemed to say that the signal 
> output dropped whilst the K3 was still in TX, i.e. you say " during 
> PTT transmit ". So was the TX indicator active during "my transmit 
> audio cutting out" ?
> 
> This would indicate no problem with the ptt, but the audio - signal 
> circuit chain, or rfi issues. Can you clarify please?
> 
> I guess Don interpreted your original post different to myself. I 
> would test sending dits into a DL for the same period to check power 
> level consistency before looking at other areas.
> 
> -----Original Message-----
> From: elecraft-bounces at mailman.qth.net 
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Keith Heimbold
> Sent: Friday, 27 July 2012 10:53 PM
> To: don at w3fpr.com
> Cc: Elecraft Group
> Subject: Re: [Elecraft] K3 transmit audio cuts out
> 
> Hi Don,
> 
> Thanks for the quick recommendation. I will give that a try this morning. 
> 
> I did a complete switch out of the headset, PTT switch and adapter and 
> experienced the same cutout. I did consider this being an RFI issue. I 
> was doing a bit more ragchewing then usual last night.
> 
> I will try your recommendations and report back.
> 
> Thanks,
> 
> Keith
> AG6AZ
> 
> Sent from my iPhone please excuse typos
> 
> On Jul 27, 2012, at 5:48 AM, "Don Wilhelm" <w3fpr at embarqmail.com> wrote:
> 
>> Kieth,
>> 
>> In cases like that, the first things to check are the external cables
>> - in
> your particular case, the PTT.
>> If you are using the mic jack PTT, try the one on the back panel - if 
>> that
> cures the problem check your cables again.
>> 
>> The other possibility is that something happened in your antenna 
>> system
> and you are experiencing RF feedback.  Run the K3 barefoot into a 
> dummy load
> - if the condition persists into a dummy load, then you can conclude 
> that the K3 might be to blame.
>> 
>> 73,
>> Don W3FPR
>> On 7/27/2012 8:36 AM, Keith Heimbold wrote:
>>> While operating last night on 20m on my K3 serial 1391, I had an 
>>> issue
> with my transmit audio cutting out during PTT transmit. Also power 
> output simultaneously dropped out completely in mid sentence. I could 
> see this both on the power meter and hear it on monitor.
>>> 
>>> I currently use a Heil proset 4 and a heil hand switch with that 
>>> rig. I
> then decided to switched headsets and switch to my heil proset 5 and 
> my foot switch which is on my other K3 to determine if it was an issue 
> with headset / PTT switch combination.  Upon transmitting it continued 
> to cut out the audio and power. I was alerted by the ham I was 
> communicating with that I was having an issue with my audio.  This 
> issue continued to persist so I decided to shutdown the system.
>>> 
>>> My configuration last night also consisted of this K3 unit being
> connected to my Yaesu Quadra amplifier to my SteppIR three element 
> Yagi. I was operating at about 500W.
>>> 
>>> This is the first time I have had any issue with this K3 unit though 
>>> I do
> experience some unusual receive issues with spurious and higher noise 
> levels with this unit versus my other K3 and my KX3.
>>> 
>>> Turns out that I am coincidentally sending up my other K3 1526 to
> Elecraft today for several mods and some additional features to be 
> added. I would like to get the older 1391 unit working before sending 1526
up north.
>>> 
>>> Any thoughts on what might be happening or troubleshooting options 
>>> would
> be great.
>>> 
>>> Thanks,
>>> 
>>> Keith
>>> AG6AZ
>>> 
>>> 
>>> 
>>> Keith
>>> 
>>> Sent from my iPhone please excuse typos 
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>> 
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