[Elecraft] [K2] Lost 80m recieve.

[Alan Davenport]

Good Morning Don,
 
     Well it certainly looks like it is a VCO issue. On all bands except 80m, it is working correctly however on 80m here are the results:
 
3.5 MHz = 11038.61 MHz
4.0 MHz = 11038.51 MHz
 
Subtracting 4913 KHz gives me  ~ 6125.6 KHz. 
 
No wonder 80m isn't working. What surprises me is that this issue is confined to just one band. What is your suggestion on what to check?
 
    Thank you again Don,
     73 de Al, W2GZN
 
 

From: Don Wilhelm <w3fpr at embarqmail.com>
To: Alan Davenport <w2gzn at yahoo.com>
Cc: "elecraft at mailman.qth.net" <elecraft at mailman.qth.net>
Sent: Monday, September 5, 2011 9:04 PM
Subject: Re: [Elecraft] [K2] Lost 80m recieve.

Alan,

First of all, transmission at a fixed frequency of 3712 is indicative of a problem with the VCO/PLL.
Are the R30 (VCO voltage) values within range on all bands?  That is the starting point.

Next put the internal probe into TP1 and measure the frequency when the K2 is tuned to 3500, and also at 4000 kHz.  The measured frequency should be near 4913 kHz above the frequency shown on the K2 display.

If the frequency is not correct, the K2 will transmit on the wrong frequency.

Give us the results from the above tests and we can proceed from there.

73,
Don W3FPR