[Elecraft] Issues with K2 Align & Test

[Ron Hahn]

Colleagues,

I've just finished the receiver section of my K2 and have run into some 
issues with alignment and test (part 2)..

First, the data:

4M Osc Test : 12,099.21 (set against frequency counter)

Ref Hi : 12,099
Ref Lo : 12,087
Range  : 12kHz

VCO Test : 8,913.08

VCO voltage readings within range on all bands

BFO Hi : 4917.62 >= 4916.3
BFO Lo : 4913.59 <= 4912.7 !!!
Range  : 4.03    >= 3.6kHz

All BFO components checked and confirmed to be correct..
BFO coil checked for shorts against resistor retainer..

Now, the problems...

1.  The BFO Lo is out of range;  This appears to have a knock on effect 
with the filter cal.  I've checked all the component values and also 
rechecked the 4MHz osc calibration, and can't get the BFO within range. 
What could possibly be wrong? Built-in frequency counter seems to be 
accurate when measuring an external reference.

2.  There is a constant broad-band S5 signal on the S-meter, and this can 
be confirmed by plugging in the headphones.  ALC works normally. Injecting 
a signal into the aerial input is masked by the internal signal (wherever 
its coming from).  Changing filter settings has some impact on the signal 
strength. This says to me that something is oscillating that shouldn't 
be??

Thanks for your help,

Ron