[Boatanchors] SX-71 (Similar Problem)

[Philip]

Hi Joe,

I had a nice SX-71 that I restored (it's long gone).  Anyway, this set is 
double conversion on the higher bands and I would look at the 2nd Mixer-LO 
circuit as that is the most likely area.  Look for a shorted capacitor 
bypassing a B+ line to that circuit, or possibly an open IF transformer on 
that stage (bad tube?) Also, that model had problems with IF transformers 
developing leakage, but that usually affected the AGC, not killed the set.

73 de Phil,  KO6BB
DX begins at the noise floor!

THE BEACONEER'S LAIR:   http://www.geocities.com/ko6bb/
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Merced, Central California,    37.3N  120.48W  CM97sh


> Well, guys, as long as I'm working on the weak band on the SX-42, I pulled
> out an SX-71 with a similar problem. I might as well tackle both at once.
>
> The SX-71 plays beautifully on bands 1 and 2 but is totally dead on bands
> 3 and higher. Unless I'm reading the schematic wrong, this does not seem
> to be a set where an extra RF stage kicks in only on bands 3 and higher.
>
> Where should I start?
>
>
> Joe Connor
>