[R-390] I got my R-390 working!!

[Jim Green]

> Well, it's been a while since I posted an update. I got my R-390/ 
> URR (not A) at a hamfest
> in Baraboo, WI last summer. It came with the original shock mount  
> cabinet. I think I paid
> $300.00 for it. It worked fair to poorly from 8 Mc up, and was  
> completely deaf from 8 Mc
> down. A visual inspection yielded the following:
>
> The Kc knob is not original.
>
> The Mc knob has part of the skirt cut off.
>
> The manufacturers tag was missing.
>
> The Shaft for the zero adjust knob was missing and had been  
> replaced with a machine
> screw. The knob was clamped onto the machine screw, but slipped  
> when the clutch was
> tightened. I made a replacement shaft in the machine shop I happen  
> to have in my garage.
>
> The cam follower was missing from one of the 1st IF can rack lift  
> arms. I made a new cam
> follower in the machine shop and installed it.
>
> The cable that carries the signal from the VFO sub-chassis must  
> have been damaged at
> one time and a very kludgy repair had been performed. I couldn't  
> stand looking at it so I
> removed the VFO sub-chassis and replaced the cable.
>
> At this point the receiver was almost completely deaf.
>
> I found this rather depressing so I walked away from the project  
> for a while. A friend of
> mine offered to help me get it going so yesterday I hauled the  
> beast over to his house and
> we started in.
>
> Basically all it needed was an alignment. A previous owner had  
> tried to perform an
> alignment without the cam follower. Once I had replaced the  
> follower it was all messed
> up. Now it's properly aligned it hears quite clearly all the way  
> from 500 kc to 32 Mc. Some
> of the Xtals in the Xtal oscillator are more energetic than others,  
> but it's nothing I can't live
> with for now.
>
> The only issues I have left are the following:
>
> There seems to be a bit of backlash in the tuning. I can turn the  
> Kc knob roughly 10
> degrees without any movement of the Veeder root.
>
> The ALC does not seem to be functioning properly. I can detect no  
> difference between the
> ALC position and the MGC position. The Function switch is working  
> properly. Pin seven of
> V511 shorts to ground when the position switch is in the MGC  
> position (like it should).
> Perhaps I'm missing something but shouldn't the AGC prevent  
> distortion when listening to
> a very strong signal? It seems to me that I shouldn't have to ride  
> the RF gain when the ALC
> is in.
>
> I couldn't find any information in the manual. Any recommendations?
>
> Jim KG9MM
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