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Probably in the wrong area BUT those who use or have used an R-390a for SWL or number station hunting...Do you

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Total Members Voted: 4

Voting closed: December 21, 2021, 1502 UTC

Author Topic: R-390a Users  (Read 2863 times)

Offline M R I

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Re: R-390a Users
« Reply #15 on: January 05, 2022, 0036 UTC »
As far as stability on the R-390A I re worked the cosmos PTO VFO for mechanical stability and now after full warmup the drift is now 4Hz with the heaters off. Just amazing for a receiver that is 59-71 years old.
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Offline Charlie_Dont_Surf

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Re: R-390a Users
« Reply #16 on: January 05, 2022, 0226 UTC »
We had one decades ago at the club station at my university. The enclosure was pretty beat up with a lot of scratched paint. Maybe it was banged around a bit in the Korean or Vietnam Wars. It worked OK but I always felt like it needed an alignment since it it felt a bit "unresponsive" and maybe the AGC wasn't quite right. In any case, I listened to many hours of Radio Dublin and Radio Fax (the station, not the mode) on that bad boy.
I don't STRETCH the truth.

"Every minute I spend in this room, my signal gets weaker.
Every minute Charlie squats in the bush, his signal gets stronger."


Item image   Analog Electronic Music Techniques - book - 423 pages - 1985 - hard cover - slip