The GE Superadio Tech Page
This page is designed to give you quick, accurate technical information about the GE Superadio series of radios. I personally own all three basic models, so I can speak a lot about them. I cannot speak definitively about boombox version with casette, but supposedly the core is based on the GE Superadio series.
Since these radios have been discontinued, I propose that the reader might want to try the CCradio-EP, which is a recently introduced radio with performance that I find superior in almost every way. It is available from CCrane.
The Superadio models are all based on a TDA1083 IC, which is one of those "radios on a chip". It contains the circuitry necessary to make a radio - including an audio amplifier. All you really need to add are antennas, IF filters, a volume control, and a speaker and you would have a good - but not excellent radio. GE has added external circuitry to give it a tuned RF stage on AM and FM, 3 IF filters for FM plus a 280 kHz ceramic filter, four IF stages for AM, bass and treble controls, etc. It just goes to show the excellent radios that can actually be made out of these "single chip" radios. There are other ICs available - by far the most common are ones that do not include an audio amplifier, but have integrated FM detection or detection in an external ceramic discriminator. All of these IC's could theoretically be used to create their own "Super Radio" design - but no manufacturers have seen fit to do so.
Data Sheet Links:
The bad news - it appears to be discontinued. The good news - NTE makes an exact replacement, the NTE1624:
It is available from Mouser Electronics. I have ordered them from Mouser, and used them in GE SR's 1 and 3 - they work. Since the 2 is just a minor variation of the 1, I am sure they would work in it as well, I just haven't replaced one in a 2 yet.
While I am quite impressed with the performance of these models, they are relatively low cost portable radios compared to communications grade receivers. Quality issues plagued the product from the very beginning, reaching the point in the Superadio 3 that returns doomed the product. It is currently out of production, and I would be very suprised to see the product revived as a Superadio 4. I will go into the quality issues with the "3" in more detail on its tech page.
The following photomicrographs show details of circuit board quality issues:
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| Cold Solder Joint | Over Etched PC Board |
There are also numerous component leads that are left too long when clipped, and can short against adjacent traces (these do not show well under the microscope).
For more technical information on your particular model, click on its title headings below.
The original GE Superadio, sometimes mistakingly called the GE Superadio 1, was introduced sometime before January 1979 (the date on the manual), which indicates that the design is at least 30 years old. There have been two versions - one without external antenna connections and one with external antenna connections.
The GE Superadio 1 and 2 are very similar, but several changes were made:
There were several minor revisions made during production of the GE SR-2, mostly affecting the case.
The Superadio 3 was a major redesign of the product. Changes include:
Make no mistake, the "3" is nothing more than a derivation of the "1" and "2" designs. The schematic shows many common topologies - modified to accomodate the varactors and bandwidth switch on AM - but the circuit architecture of the "3" has otherwise changed very little. The reference designators on the schematic and PC board have changed, but their functions, and sometimes even values are the same as the "2".
The Superadio 3 has gone through one major revision, in which the front end of the FM section has been changed from discrete transistor techniques to a single-in-line integrated circuit. I do not have the schematic of this re-design, but I do own both versions, and have included photographs of both in the SR-3 tech page.
The Superadio 3 has also gone through a transfer of ownership from GE to RCA. All RCA versions contain the new PC board design, while only the last few years of the GE production have the new PC board design.
As nice as they are, GE Superradios can't be all things to all people.
GE has a history of making fine radios that extends back into the 50's, less than a decade after the invention of the transistor. After much searching, I found a reasonably priced GE P-780:
After doing a restoration on the radio, I can conclusively say that this is not a predecessor or precursor to the GE Superadio. Other than being radios with tuned RF gain stages, the two designs are completely different. They may well have had some designers in common, but the Superadio designers took advantage of new technology - the aforementioned "radio on a chip" IC to do their design. The P-780 has three IF stages, the Superadios 4. And, of course, there is the addition of the FM band on the Superadios. There is an AM/FM version of the P-780, but I don't have an example to examine to see if it contains tuned RF stages on both AM and FM. Based on the interior space in the P-780 cabinet, I doubt it.
I have received many inquiries about the Radio Shack Optimus models 12-603 and 12-903. Many people have claimed that they are nothing other than repackaged GE's. This is not true. Both are fine radios, but they are complete redesigns that cost reduce the GE. Consequently, the performance is not as good. I own one, and have analyzed it at the link above.
Now that the GE / RCA Superadios are out of production, many people are looking for a "replacement". Many radios have been touted as being excellent AM performers:
I own the first three listed above, and some Sony models that are good - not great. But I can't vouch for ones I haven't tried. I have a couple of other non-GE/RCA "superadios".