[Hallicrafters] SX-122 BFO

[Dan Cotsirilos K9DTC]

To Roy who had good suggestions and to it may concern. The BFO trouble wound 
of being mechanical. Some where in time, this radio was not used for awhile 
and maybe then only for Shortwave listening, the BFO knob must of been hit 
hard?

I was attempting to take the inner collar off the shaft when I didn't notice 
that the collar had a set screw because it was pushed back!

Pulling on the collar placed the shaft back in the correct position and now 
the BFO works perfect. Thank you Roy again for you time.


Dan K9DTC



----- Original Message ----- 
From: "Roy Morgan" <roy.morgan at nist.gov>
To: "Dan Cotsirilos K9DTC" <dcsfree at comcast.net>
Sent: Wednesday, March 01, 2006 9:55 AM
Subject: Re: [Hallicrafters] SX-122 BFO


> At 08:41 AM 3/1/2006, you wrote:
>>Ok Roy
>>
>>    What you are saying is that there is no other adjustment and it must 
>> be bad component surrounding the tube?
>
> Dan,
>
> I am not familiar with the SX-122 circuit, but I would expect a frequency 
> adjustment, not a level set adjustment.
>
> The things to suspect are the capacitors and the resistors associated with 
> that circuit.  Test the screen and plate voltages as a start.  Then with 
> power off, measure the resistances.  From that you can tell if you have 
> bad components. It's very common to have resistors that have drifeted very 
> high in value - this would cause low BFO strength.
>
> Roy
>
>
> - Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
> 7130 Panorama Drive, Derwood MD 20855
> Home: 301-330-8828 Cell 301-928-7794
> Work: Voice: 301-975-3254,  Fax: 301-948-6213
> roy.morgan at nist.gov --
>