[Elecraft] SSB TX audio problem. Need help !

[Jean-François Ménard]

I forgot to say that eveything was OK in CW... The problem was only in SSB.

73

Jean-François Ménard a écrit :
> A very strange way to solve my problem was to «hard reset» the K2. And 
> setting up from scratch with all needed values.
>
> This is the second time that I solved a problem with a «hard reset». 
> The first time, a friend of mine brought me his K2 because he had TX 
> problem in CW. His problem was like he was transmitting 7-8 kHz wide 
> in CW. All BFO and filters values were OK, but after a «hard reset», I 
> set again all values and everything was working fine.
>
> I got another strange problem here with mine this time. On TX SSB, 
> people received me like I had RF feed back. I recorded my audio myself 
> with my computer, and yes I have ripple in my TX.... even with 
> different microphone, and at 5W in a dummy load.
>
> A reset cure the problem, or at least, since the reset, I did not have 
> the problem anymore. I connected my PC audio to my K2 mic with an 
> adapter using an interface between them and transmitted in a dummy 
> load a few MP3 over the air. The received signal on my KX1 seems to be 
> all OK now. Now glitch or ripple.
>
> It seems to me that some values written in the EPROM was corrupt, or 
> at least, not good...
>
> Does anybody got the problem before ?
>
>
>
>
> Don Wilhelm a écrit :
>> Jean-Francois,
>>
>> Can you check your microphone?  That sounds a lot like a bad mic 
>> element to
>> me.  Try another mic if you can - if you are wired for the electret mic
>> (with the resistor), then you can even use one of the inexpensive 
>> computer
>> mics.
>>
>> In any case, substantiating that the mic is good is the first step in
>> troubleshooting a problem like you described.
>>
>> As an alternative you could feed known clean audio into your K2 from an
>> audio generator, or even make up a voltage divider and feed audio 
>> from the
>> computer soundcard or a portable CD Player into the K2 (just don't 
>> transmit
>> on the air).  Using a controlled audio source will allow you to 
>> troubleshoot
>> a problem inside your K2 with your 'scope much easier than trying to 
>> do it
>> live with a microphone.
>>
>> If you do not know how to build up the voltage divider required, take 
>> a look
>> at some of the PSK31 'how-to' websites for the simple interface 
>> schematics -
>> you need only the soundcard output half of the interface.
>>
>> 73,
>> Don W3FPR
>>
>>  
>>> -----Original Message-----
>>>
>>> I have a K2 that work great since 2003, but this morning.... Nop.
>>>
>>> Nothing change on my setup, I was just operate my rig this morning as
>>> usual and found this morning that my SSB TX audio looks horrible...
>>> sounds like RF feedback a few hams told me..... but...
>>>
>>> I tried the K2 on a dummy load and listened up with my KX1, and I found
>>> that when I start to speak, the audio is like «scribble» or like a
>>> defective speaker that fuzz. It seems to be worst at the beginning of
>>> the transmission. I have only 1 bar or 2 on ALC reading. It sounds like
>>> overdriven, but ALC reading on the bar graph seems OK.
>>>
>>> I also remove every options and installed my un-mod kit to replace
>>> options. I'm running the basic K2 with only the SSB adapter...
>>> nothing else.
>>>
>>> I did again the SSB calibration procedure, nothing at all, 
>>> everything is
>>> OK on this side.
>>>
>>> I tried every audio gain and compressor combination, the problem still
>>> there, not worse, not better.
>>>
>>> Does somebody have something to suggest me to start with ??? This is my
>>> first real problem from the beginning, so I don't have much experience
>>> in finding problem.
>>>
>>> I have a scope, but with not much experience on how to test...
>>>
>>> Thanks for your help !!
>>>
>>> J-F VA2VYZ
>>>
>>>     
>> -- 
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>> 12:53 PM
>>
>>
>>   
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