[Collins] 30L-1 Repair

[Robert Spooner]

Tom,

If the problem is only on 20M, I don’t see how it could be the tubes. The high input SWR points to the problem being in the input circuit. Check continuity through the band switch, and if that is OK, then look at the components in the input matching network for 20 Meters.

Please let us know what you find; it may help someone else in the future.

73,
Bob AD3K

On Jul 3, 2014, at 5:30 PM, Tom <url4603rd at comcast.net> wrote:

> Hi All,
> 
>    Posted here before about this but have a follow up question.
> 
>    I've been told that the problem is not the tuned input ckt. but the 811 tubes. I fully admit that I'm not an expert on RF Amps, BUT it has good output on all bands except 20M. The tuned input on 20M will not go below 4 or 5 : 1 , all other inputs go to 1:1.  I kind of think that if the problem is isolated to just the 20M tuned input that the logical "suspect" is one of the caps in the tuned input ckt. or am I incorrect and the 811's are the suspect?  I "do realize" that the 811's are easier to change out, but it still doesn't compute in my ole brain.
> 
>     Thanks for everyone's feedback on this.
> 
> Tom W1ALZ
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