1970 Sony 2R-31 AM 6 Transistor Radio
 

Hello everyone, yesterday I picked up at a local antique mall a minty Sony Model 2R-31 AM 6 Transistor pocket radio that still has its original leather carrying case with it that is in mint condition yet and the radio works beautifully yet, and I only gave $10 for it. I was curious as to how these fell in the Sony Pocket radio lineup as far as build quality and how high end they were (how many IF Stages/RF Stages compared to other Sony Pocket radios from the time period, push-pull output vs single ended output, etc.) and how common these were, and how reliable were the capacitors and transistors in these radios?

Any Help would be appreciated.

This may be of interest to you.

https://www.youtube.com/watch?v=cnlDvGPnaU4

The $10 was well spent IMHO. They were good little radios but never
built to last 50 yrs ! Getting the case makes it even better.
When you get into better models look for TRF radios. They have an extra
RF amp stage & big loop stick antenna. Preformance is much higher.
At sunset on the E coast ( at the shore) they can get Euro, mid east etc stations on a good day.
Also up til the mid 60's US brands had super high build quality & some
Zeniths were still hand wired.

73 Zeno:smoke:
LFOD !

I have a Sony TFM-7720W AM-FM transistor portable radio which still works well for its age (I'm not sure when it was made, but I'd guess somewhere in the late 1960s or early '70s). I don't use it much these days, but the last time I had it on it worked every bit as well as it probably did when it was new. This radio was built much better, IMHO, than most new AM-FM sets coming from Japan (and elsewhere in the Orient) today. One feature this radio has which most, if not all, of today's gutless-wonder portables don't is a tuning dial which stretches the entire width of the set's cabinet, and which shows the entire AM and FM broadcast bands, again unlike today's sets on which the tuning dial is so small (with the tuning scale not much larger than a fly speck) it is not funny (!).

These older AM/FM portables are far better performers from a sensitivity standpoint than today's poor excuses, IMHO, for AM/FM radios which don't work well if you are any real distance from the transmitters. Case in point: I live in a very small town thirty miles from downtown Cleveland, and perhaps ten or 15 miles further distant from the radio stations serving the city. I would not expect any of these small portables to receive anything much other than the 50 kW stations in Cleveland, and perhaps a small (1kW day/500 watts nights) AM station in the next town east of the city.

FM performance may be even worse. I would not expect any of these portables to receive anything much in my area except a 6kW (ERP, effective radiated power) FM station on 93.7 MHz, and the major FM stations in Cleveland. These portables are meant for use in the metro area, i. e. the primary service area of FM stations, and will operate poorly, if at all, in areas such as where I live. The sound quality is poor, but then again, these are cheap gutless-wonder portables not meant for high fidelity. I have an Aiwa bookshelf stereo system that runs rings around any of my portables as far as sound quality is concerned (200 watts total power, 50 wpc) but I expect it to outperform the portables, which it does, in spades. Its FM tuner is not the best and is not meant for use in areas such as where I live, but then again that is how these stereo systems are built these days, like it or not. I owned a Zenith 4-mode stereo system when I lived at my former residence, a Cleveland suburb; the FM tuner in that system ran rings around the tuner in my Aiwa bookshelf system.

Oh, well.

in defense of newer radios
 

On the contrary, many newer small radios are excellent performers. Jay Allen’s website has many reviews of both newer and vintage radios and is well worth viewing before totally dismissing all newer radios. https://radiojayallen.com/

Also see the “mega shootout” comparison of AM portables. https://radiojayallen.com/am-portabl...t-2019-update/

jr