The SR III is the latest version of the radio. The SR II, which many people, myself included, still own, had a different cabinet and AM coverage only to 1600 KHz; the SR III accommodates the expanded AM band. The II does not have a AM wide/narrow filter switch.
There are some technical changes as well; the III uses varactor tuning compared to the II, which uses a conventional variable capacitor.
Dave Markson has this to say about the II vs. the III:
"I have an original Superadio and just bought a SR3 (modified on FM with a 110/280 KhZ IF filter, and SCA by SCS Radio Tech). As for MW, here are my findings:
- The SR3 has much better sound.
- Although the SR3 has a wide bandwidth position, it is almost useless, but does increase the highs on local stations. The normal position is close to the bandwidth of the original SR.
- The SR3 is more sensitive (by a small amount)
- The SR3 has about the same selectivity of the original SR, my findings show it a little bit less selective.
- The SR3 workmanship is not quite as good as the original SR.
- The SR3 is harder to tune. Where as the original SR band was spread out pretty evenly across the dial, the SR3 uses 1/2 the tuning dial to go from 530-1000kHz, then crams the rest on the right half of the dial. Tuning the upper portion takes a very steady hand! Calibration is terrible also.
Note: I bought a Select-A-Tenna, and it improves reception on both SRs. A GREAT DEAL. Well worth the $40-$50 (hmmm, same cost as the SR3.)
As for FM, here are my findings:
- The SR3 has much better sound.
- The original SR is MUCH more sensitive than the SR3. It is possible that this is due to the modifications, but I'm not sure. Anyone comment on this?
- The 110/280 kHz IF filter is a great idea. The SR3 has a stock 180kHz filter.
- Using SCA is great. I am a little disappointed that there are so few SCA programs in the greater Boston area. Most stations are transmitting data on their subcarriers. SCA requires a very clean local signal. There is no DXing SCA stations.
- SCS does a very clean, professional mod. [No relation to SCS]
The original Superadio resembles the SR II, except that it has only one speaker; performance is similar [Scott Fybush]
There was a digital Superadio, the Superadio
Plus.
To paraphrase Dave Zimmerman, this model (#7-2882) was introduced
in 1982, with many of the same features as the original SR, but
with PLL synthesized tuning! No keypad, but there were eight
presets for each band, a lighted display, and a 9 kHz/10 kHz
tuning step switch in the back.
Compared to the analog SR, the performance is close, but with increased noise on AM probably due to synthesizer noise. For the same reasons, weak FM signals were difficult to "lock on" to, compared with an analog radio.
It was a pricey radio in 1982, at $139.95, which likely made it a quick departure from the market.
Dave's full review is available
elsewhere in the FAQ pages.
See also my comments on a digital SR.
Radio Shack does not sell any rebranded GE radios. They do sell some "high performance" AM/FM portable radios that are similar.
A current model of theirs is the Optimus #12-903.; this seems to be the successor to the Optimus #12-603, an AM/FM radio and Optimus #12-604, which is an AM/FM/TV-sound radio (which includes the UHF channels, unusual for a TV-sound radio.)
A report on the #12-603 from C.D. Kolyer:
I bought this "new product offering" from Radio Shack, because it looks like and has many features of the GE Superadio III- separate Bass and Tweeter speakers, "tuned RF on AM and FM", wide-normal bandwith switch, external antenna screw terminals, obnoxious top-mounted Power switch. Knowing how Radio Shack buys its product designs from others, I believe this is a clone of the Superadio.
Like everything electronic in my house, I opened the radio. I found "SUPER RADIO PCB TOPSIDE CITY 50496" silkscreened on the PCB. The ferrite bar is 140 mm long, which is not as long as the one mentioned in advertisements for the GE Superadio III at web sites such as Universal Radio or Grove.
I'm not an experienced DXer, and I usually laugh at Radio Shack's products, but this relatively inexpensive ($ 59.99) receiver performs very well. Also, remember Radio Shack's return policy (90 days w/o hassle- buy one, save the box, test it out, return it if you're disappointed...) I know of no retailer near me who offers the GE Superadio, and I have a problem with re-stocking fees associated with mail order. Besides, Universal Radio and Grove have a price within pennies of $60.00 for the GE Superadio.
Columbia River Consultants has written a review of the RS radio in which the reviewer finds the radio poorly aligned as it comes from the factory. A realignment gave excellent results. The review's at http://www.geocities.com/CapeCanaveral/Hangar/8905/RSSR.html.
Compared to the average radio, you will get better reception. In 1994, over a few weeks of listening, I compared the SR II to my Realistic DX-400 (with an external antenna), listening both in the day and at night; I lived (and still live) directly on the East Coast, 25 miles NE of Boston, Massachusetts. The results:
Daytime AM (mediumwave)--I found a dramatic improvement. I could regularly get several New Hampshire news/talk stations, including WNVU 900 and WZNN 930, that come in weakly with the DX400, if at all. Not to mention New York stations like WCBS 880 and WNYC 830, plus the stupendous (and, alas, now off the air!) CHSJ 700 in St. John's, New Brunswick, Canada. The SR's antenna really cuts down the noise that is ever-present during the day.
Nighttime AM (mediumwave)--When the ionosphere is 'on', almost any radio will hear DX. But the Superadio receives DX more consistently, and with better selectivity than any other cheap radio I've used.
Although the Superadio has only imprecise slide-rule tuning, I can regularly resolve different stations 10 KHz away from each other. And unlike so many shortwave portables, there's no overloading, at least not on the internal antenna.
Also, as mentioned previously, the radio has excellent sound that'll enhance your listening in almost any situation.
People have spoken well of the Select-A-Tenna, an external loop antenna, sold by Grove Enterprises, C. Crane, and other, and is about $60.
I've used my Superadio with a homemade clone of the Select-A-Tenna, available from Werner Funkenhauser's site at http://www.carcanada.net/dx/. I've also used it with Radio Shack's loop antenna (#15-1853). These antennas don't make as dramatic a performance jump as you might see with other receivers, since the ferrite rod in the SR is already a good performer as it is.I've used the SR with my Carpet Loop antenna, with good results. A few years ago, I had some very interesting results using that antenna for MW with the DX400; I once was able to receive both WJR and Radio Reloj on 760 KHz at will by flipping a knob on the antenna.
In general, loop antennas are a good choice for mediumwave listening. The National Radio Club publishes loop plans; their address is in the appendix.
Generally, any antenna labeled as "FM" or "TV/FM" should work. The FM antenna terminal on the SR will accept the usual 300-ohm TV twinlead terminals. Some suggestions from the Radio Shack catalog, from least to most elaborate:
Don't overlook the TV antenna you may already have; it should work fine with the SR.
Some people have reported poor sensitivity on the III when it was first released. Radio World (3/24/93) quoted a spokesman for Thomson Consumer Electronics indicating that some early models of the SR III have severe sensitivity problems.
These early models had the following date codes, a 4-digit code found on the box or in the battery compartment: (the first digit is ignored) x201 through x241. There is a suggested fix in Appendix A
During 1996, many people reported buying SR's that turned out to be defective, usually with poor sensitivity. Sadly, it's not uncommon to go through several SR's before finding one that's satisfactory.
GE's parent company, Thomson, is experiencing business difficulties which may account for the severe quality-control problems the SR seems to be experiencing. Indeed, this has put the future of the Superadio in doubt.
In the meantime, if you haven't bought an SR yet, make sure you pick a retailer with a liberal return policy. If you're buying used, insist on operating the radio and checking it thoroughly before money's exchanged.
If you've already bought an SR and suspect problems, read the suggestions here and in Appendix A
This is a common problem with slide-rule radios such as the SR. Many of us who are used to digital displays are thrown by this.
Andy Sennitt suggests using graph paper to plot frequencies of known stations versus the dial log, which is marked from 0 to 10, in tenths, on the Superadio.
I'd suggest graphing small segments of the band (say, 800 to 900 kHz), until you get the hang of it. One can get within 10 kHz, which is good enough for most purposes.
(I last did this trick with a Realistic DX-160, which I used aeons ago. How soon I forget.--DM :))
The Superadio has an earphone jack--but it's a stereo 1/8" jack, the same as in your portable CD player. You can get a stereo-to-mono adapter at Radio Shack (RS #274-374). When my mother had an SR, I put a 1/8" stereo plug on her pillow speaker so she could use it with the radio.
NOTE: The SR is still mono, whether you use a stereo headset or not.
Yes. Several manufacturers sell kits and assembled boards that can be used with the SR. SCS and Ramsey sell boards, while Bruce Elving sells complete Superadios with the modification. Here are Joe Jesson's comments on the SCS board:
"I recently ordered and received three SCA demodulator boards from SCS Radio Technology after noticing an advertisement in Radio News. Bruce Elving's SCA design uses a CA3089 IF/detector chip and a PLL (I designed his XR2211 PLL SCA demodulator) SCA. Bruce also sells FM receivers modified with the boards.
What was interesting about the SCS SCA board design, while it uses a CA3089E IF chip also, a multipole filter in front of the 3089 decreases main channel crosstalk interference (by 60 dB). David's board is of excellent construction, with no jumpers and small size to be inserted in an FM receiver's FM detector stage (before deemphasis attenuates the SCA signals).
Anyway, three pretuned boards are available from SCS, 57Khz, 67Khz, and 92Khz - $20.00 each, $60 plus $6.00 P&H for all three. I am satisified with the design and construction of each board. One area of modification I would make is to monitor the SCA signal's multipath and level with an x-y monitor. Use pin 13 of the 3089 chip for a signal level (scope y) output and pin 7 for the x axis output. Of course levels must be set to set vertical and horizontal traces. A flat vertical line, max amplitude, is the ideal signal for tuning. A "wavy" line illustrates multipath. This is a great tool for tuning FM signals...
GE sold the Superadio rights to Thompson Consumer Electronics, El Paso, Texas. The Superadio III will continue to be sold under the GE name.
Thomson Consumer Electronics has told at least one person that service manuals are no longer available.
There's a copy of the SRIII service manual at http://users.netonecom.net/~swordman/Radio/GEsrIIIAlign.htm.
The last known address for service manuals was:
Price of the manual in 1993 was $6 plus $3 handling; it's recommended you call first to confirm pricing. When ordering the manual, be sure to include the model number and suffix, as the service data is revised with production changes. (My SR II is #7-2885F; the SR III is #7-2887.)
Additional alignment instructions are available at http://www.paulplu.demon.co.uk/sr3/.
There are several reasons for this:
Remember that the Superadio is aimed for the "average" consumer; at US$50 retail, it's near the high end for a radio of its type (AM/FM, no stereo, no cassette). A digital display would make the SR more expensive than it is already. GE isn't Grundig. Nor is it Bose.
Also, a digital tuner (PLL frequency synthesizer) has some associated performance disadvantages: Synthesizer noise affects audio, causing hiss and low bass response. "Birdies" and intermodulation distortion, all too familiar to shortwave portable owners would probably make an unwelcome visit, especially as any digital tuner suitable for the SR's price range would likely be single-conversion, rather than the double-conversion used in most shortwave sets.
The biggest problem with a GE SR digital tuner, though, is one that could alienate many Europeans, Asians, Australians and trans-Atlantic/trans-Pacific DXers: The 9 kHz/10 kHz split.
Most of you know that North American MW stations are separated every 10 kHz and European and Asian MW stations are, in contrast, separated every 9 kHz. I'm sure more than one American tourist has cursed when they can't tune local stations from their hotel room overseas.
As mentioned earlier in the FAQ, GE doesn't market, let alone modify, the SR outside of North America. Given this, the splits in a hypothetical digital SR would probably be hardcoded for 10 kHz. If it were Sony we were referring to, there'd probably be a 9 kHz/10 kHz switch in the back. But the SR? I don't think so.
That said, I've owned three different portable digital radios, and all of them have had some provision for changing the MW channel spacing, usually through a switch in the battery compartment, though my latest Sony radio requires you to hold down a button while turning the radio on.
Dave Zimmerman has an alternate opinion: a very interesting review of the Superadio Plus which is presented elsewhere in this FAQ.
A generic frequency readout is available as a kit from Almost All Digital Electronics ; this can be added to many older analog radios. Cost is $50, and detailed connection diagrams are provided for many different models.