RCA 8R71

[19&41]

A tabletop AM/FM radio in natural bakelite. My grandfather had one of these on the stand next to his recliner. My cousin and I would listen for the school closure announcements on it. after restoration and alignment,the FM was wonky on it until I reglued a coil that had been duco cemented to the top chassis. These also came in several woodgrained colors.

[TC Chris]

Most of those early AM-FM table radios had limited FM sensitivity. FM was contemplated as being a purely local medium so they didn't aim much for DX work on the band. I'm wondering how that RCA does?

Chris Campbell

[19&41]

It does about as good as a more modern FM radio with no external antenna. Propagation is a bit disappointing around here as the terrain is not open line of sight with Atlanta. An antenna 10-15 ft off the ground does much better.

[electra225]

Does the chassis in that radio use the 12AL5 ratio detector?

[19&41]

It uses a 6AL5 ratio detector.

[Motorola minion]

Back in those days of pre-Conelrad , maybe one or two FM stations were available in any city of size (>10,000 pop) when an AM station or two was already in town. Most times it was owned by a newspaper, just like the early TV stations. Often, the same program was simulcast on both bands. Unless you were willing to connect a VHF roof antenna or at least a good twin-lead dipole, the built-in (AC cord sleeve capacitively-coupled) was not good for much unless you had a Zenith or an RCA like this one. Hence, FM was a step-child of broadcast until high fidelity became a desirable feature.

I looked at the schematic of this RCA and it is a console in a table cabinet using 6V6, it has a power transformer!!!

I have a few AM-FM radios of this period, all series heater, and a look at ratings in a 1951 Consumer Reports (CU) bears out some of the observations I have had in my own collection. It seems some brands were leading the pack in early FM, like rivals Zenith (thanks to Edwin Armstrong's patents) and RCA Victor (already building TV tuners) BUT others, fearing patent infringement designed some real poor FM receivers. The 2-3 post war Motorola and Philco table top plastic radios I have had were terrible FM receivers .

[19&41]

I also have a 68R1 waiting to be restored. It'll probably have to wait until I get more off time next year.

[electra225]

I have four and a half examples of the big RCA AM-FM radios. I have three 6-RF-9's and a 6R81. RCA was into TV, not so much into FM like Zenith was. I will give RCA the fact that their big transformer FM radio chassis didn't give anything to Zenith in the way of performance. Mine seem to handle the digital stereo composite currently broadcast fairly well. Certainly better than Magnavox tube tuners without AFC. I had a couple RCA radios that I sold at the auction. One had an eight-tube hot chassis with a 35W4 rectifier. The other had basically the same chassis with an extra tube in the front end, then had a selinium rectifier. The one with the tube rectifier was a pretty good radio. The one with the solid state rectifier not so much. I never got too deep into it, but suspect part of its trouble may have been a weak rectifier. I'd put the big nine-tube RCA AM-FM power transformer chassis up against any Zenith ever built.

[19&41]

It seems that selenium rectifiers don't age well.