[Elecraft] K2 BFO problem

[Don Wilhelm]

Snowy,

It sounds as though you have the proper BFO crystals installed at X3 and X4.

Do check the values of C173 and C174 first
Then check L33 to make certain it is well soldered and the leads are 
attached to the 1/8 watt resistor leads.
Check D37 and D38 to be certain they are oriented properly and well 
soldered.

Lastly, lift one side of L33 (and its resistor and remove the rubber pad 
- check the resistance of the pad itself - there were a few (a while 
ago) that were found to be conductive causing problems such as yours.  
Since you did not state the vintage (or serial number of the K2), do 
that check if those items above do not correct the problem.

While you have the rubber pad out, make certain that about 1/2 of the 
stem has been cut away.  That is to allow the 1/8 watt resistor to be 
pushed down into the center of L33 to tighten the leads and hold L33 
securely in place.

If the rubber pad under L33 is found to be conductive, get a new one 
from Elecraft, or -- If you have an unassembled KAT2, you will find 
several of the rubber bumpers in that kit - a conductive one will work 
fine in the KAT2, but not in the BFO circuit.

73,
Don W3FPR

On 12/16/2021 5:35 PM, ROLAND HOWELL via Elecraft wrote:
>
> having repaired my PLL problem with a great deal of help and advice 
> from Dave at tech support, Elecraft i moved onto the next set of tests 
> which was the bfo frequencies, on selecting CAL, Counter i get a 
> reading of 4.9136, on pressing either the band up or down all i get is 
> zero's.
> Fitted crystals are 4.91s in X3 and X4 positions
> Have checked all the details in the trouble shooting paragraph, i can 
> find no fault with any of the components, all values and positions are 
> correct.
> I have to add that this was purchased as a non-runner.
> Any advice appreciated
> Snowy,G0HZE
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Elecraft at 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 don at w3fpr.com