[Milsurplus] R390

[Gordon Smith]

HI Mike,
Google is your friend here: 
https://www.r-390a.net/Pearls/sensitivity_alignment.pdf

I have never had an R390 (yet.. ;) ), but from everything I've read 
these gorgeous pieces of electro mechanical engineering do require a 
well done alignment to make them work correctly. That's not even 
talking into account the alignment procedure done for the PTO.

But as your first check, I'd go with your gut and check the tube 
first. Enjoy your inheritance :)

73, Gordon KJ6IKT


At 08:55 AM 8/23/2020, mike christie via Milsurplus wrote:
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>I've  inherited  an R390 it doesn't have a data plate on it so I 
>can't tell if it's A or not.  I have it up and running but the 
>sensitivity is really bad on all bands.  I can hear WWV on 10 and 15 
>Mhz but not really strong and I went to the Amateur bands and I 
>could hardly hear anything there either.  All the controls are 
>working such as the BFO, limiter, Broad & Sharp,  RF gain etc.  All 
>the tubes are lit and I am getting background  noise. I've switched 
>between antenna inputs and I get the same results.  When I'm tuned 
>to WWV the Dial is correct for at least on  10 & 15 MHZ. Also I can 
>hear when the antenna is plug in also.  So since I'm getting back 
>ground noise on all bands,  I'm thinking I've got some bad tubes at 
>least on the front end.    I've used one when I was I in USMC so I 
>know what their capable of.
>Can some give me some pointers as to what maybe the problem?
>Thanks
>Mike
>W1ZFB