Many thanks to SWLing Post contributor, Dan Robinson, who writes:
Over $2k for this receiver, which appears to be quite unique. It is not one of the well-known and quite rare Beckman 51J4s, and likely it was re-finished to give it the almost white-grey color it has.
But it does have an interesting tuning addition, what the seller calls a factory-installed 4:1 vernier knob. Regardless, it fetched about as much as any 51J4 has ever brought in on Ebay:
http://www.ebay.com/itm/181975178674?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Thanks, Dan! That 51J4 is a beauty. I’m always amazed at the price Collins equipment fetches at auctions and even at Hamfests. You’re hard-pressed to find anything under $800 and rare units (like the 51J4 above) sell for so much more.
Someday, I’d like to add a Collins R-390A to my collection, but first I need to make room for it and start saving! My buddy, Charlie (W4MEC) has rebuilt several R-390s and I’ve no idea how he does it. The tuning mechanism alone is one amazing (and complicated) piece of engineering! Charlie loves a good challenge, though, and he’s certainly brought a few R-390s back into full service.
I spent countless hours using R-390A receivers while on duty as an intercept operator. Simply put, I loved it – the job and the rig. It was a natural extension of working Ham CW contests and Field Day operations. I sure do miss those days. There was was need for a bit of artistry in pulling out weak and fading signals and selectively walking through pileups to pick out targets of interest.
That is a good summary, would like to see some of these new SDR / DSP radios Tecsun, Countycom etc. The R390A is a good benchmark for comparison.
Sherwood Engineering’s highly regarded table of receiver test data has been a respected source for years: http://www.sherweng.com/table.html
Although it lists mostly modern gear (FlexRadio, Hilberling, and Elecraft products rate the highest in Sherwood’s methodology), there’s a smattering of vintage radios that have been tested: Collins 75-S3B, 75-S3C, R390A, etc.
Most of the equipment testing done for the (defunct) Passport to World Band Radio annual books was performed in Sherwood’s facilities.
I’m looking for an HRO-M…. and a winning powerball ticket! 😉
Bwah ha ha!!!! Well played, sir!
That was built in the days when they knew how to build radios. It most likely to have far better performance with image rejection and inter modulation distortion than any solid state radio today.
The only drawback is the size and weight of them, also the power draw, but that can be a benefit on a cold day.
Has anyone done quantitative tests of modern shortwave radios and compared them to some of these oldies?