[R-1051] Troubleshooting/repairing R-1051 - advice needed

[Tony Snider]

Nick,
Give me a call before you venture into the pa tubes and alignment thats a nightmare of a different sort!!

When you do the alignment, the capacitance of the radio being in the case effects the alignment, so you have to "lead" the alignment or i made a metal plate that attaches to top row of dog screws and simulates the radio in the case!!! Haha but it works!!! 
And dont get me started on a conductively cooled glass tube!!!  Why they used that hard to find,  delicate, tube instead  of a 4cx250b is just beyond me, and that little foil heat conductor thing that you have to wedge in there between the tube and heat sink.... If you get it in there anyway but perfect, the first time you heat cycle the tube... Crack!!!!   

Sent from my iPhone

> On Oct 21, 2014, at 7:44 PM, Nick England <navy.radio at gmail.com> wrote:
> 
> Here's an update on my adventures in 6-pack land. I've always
> enjoyed reading contributions to the archives when others have described
> their adventures in troubleshooting and repair so here goes.
> 
> Not having extender cables or a junker 6-pack to use making some, I figured
> I could at least remove the covers from some modules and poke my scope a
> bit deeper into the innards. Following Tony's suggestion, I first made sure
> the 1mc crystal switch motor was motorizing OK (particularly after I
> noticed a small setscrew had fallen out of the 6-pack when I removed it).
> Yep motor is OK and the 1mc injection freq changes OK across the 2-29  mc
> range. Don't yet know where the itty-bitty setscrew came from.
> 
> So on to the 100 cps module (this seemed counterintuitive until I had read
> deeper and found its contribution is mixed into the 100kc injection loop).
> No signal at TP3, junk at TP5. Scope probed the 11kc signal coming into the
> top board (7.1mc filter) of the 100cps module -OK. But the signal
> disappeared on the other side of Q1, a simple emitter follower. Huh?
> Disassembled the board to test Q1 - not just dead but the base lead was
> broken (how did that happen?). Soldered in a replacement and .......It is
> alive I tell you, alive!. Rcvr seems to working fine now.
> 
> I was Really Really Lucky - I could find and fix the problem without an
> extender or burrowing deep into these cordwood modules. And an exact
> replacement 2N706 was sitting there when I pulled out my misc transistors
> parts drawer (I got lots of tubes but just a handful of them squalid state
> things).
> 
> I'm sure I'll be encountering more problems and learning more as I play
> with these R-1051 machines. After the URC-35, I have a couple of 1051's, a
> D model, and a G model awaiting attention some day. Old radios sure are fun!
> 
> Cheers & thanks for the advice & encouragement,
> Nick England K4NYW
> www.navy-radio.com
> 
> 
>>> On 10/19/2014 12:28 PM, Nick England wrote:
>>> 
>>> ....
>>> The rcvr had very low sensitivity. RF stages checked OK, but some test
>>> points on the 6-pack weren't showing much of anything on a scope. So I dug
>>> a -1051D out of the garage and swapped in a 6-pack. Voila - rcvr works
>>> fine
>>> now. But now I need to fix the original 6-pack.
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