[Elecraft] K2 bandwidth modification issue

[Phil Wheeler]

I'm reading with interest, Steve. I build my K2 
early on (#380) and have done many of the mods, 
but not that one as yet -- xtals earlier but not 
all the caps, etc.; I'm not excited by working on 
that closely-spaced board. (I'm just returning to 
it after a ten-year hiatus, and have done other 
updates in the past week). So I'll be following 
your results here as part of my decision-making 
process :-)

73, Phil

On 2/10/14, 7:09 AM, Steve Garwood wrote:
> Don,
>
> I am not the original builder of the K2, so I will be downloading
> Spectrogram. I will go through the individual connection points for the
> swapped crystals and capacitors with the ohmmeter to make sure that there
> are no connection issues.  Thanks for identifying a troubleshooting path!
>
> I will advise on results.
>
> Thanks again!
>
> 73,
>
> Steve, N0CZV
>
>
> -----Original Message-----
>
>
> Steve,
>
> How does the OP1 filter passband look when viewed on Spectrogram? It should
> show a nice flat passband.  If it has a dip or valley in it, look for a bad
> connection on one of the capacitors or crystals.
>
> What is the possibility that you damaged one of the thru-plated holes when
> removing the old crystals and capacitors.  Use the schematic to determine
> 'which is connected to what' and check all those connections with your
> ohmmeter.
>
> You may also have a problem with T1 or T2 soldering or a poor solder
> connection in the switching diodes or R-Paks.  Re-flow the solder in those
> areas with a hot (750 degF) soldering iron.
>
> 73,
> Don W3FPR
>
> On 2/10/2014 2:30 AM, Steve Garwood wrote:
>> Hello!
>>
>> I am working on a K2,  <3000 s/n in which I installed the K2 SSBCAPKT
> along with the 14 crystal kit.
>> Receive is working, audio level is low on the OP1 filter, normal on FL1,
> etc.
>> I have transmit, with good audio, however, no measurable power output or
> ALC reading.
>> I've been searching for something similar to this, no luck so far.....
>>
>> It seems that the filter output is low, but functioning.....  Alignment
> addresses adjusting BFO frequency, but nothing about output level.
>> I checked soldering again, but I have not made it any further than
> this....
>> Any ideas?
>>
>>
>