I just got one identical to yours the other day.The FM is great but the rest of the bands are dead on it.I also have another one,circa 1967,with the push buttons across the top of the cabinet.All the bands work but the AM band.The "Strato World" was RCA's version of Zenith's Trans Oceanic.Sears made a nice version of it as did Hallicrafters,Admiral and a couple of others.The World Monitor was a nice sounding set.I'm hoping that by playing both the AM will come back on its' own:I had one old transistor radio,many years ago,and the reception came back on its own.That radio uses a wall wart as opposed to the '67 version that uses a built in power supply.My '67 version was given to me.I ended up losing the closing doors to it;they're around here someplace.
my dad gave me one of these radios. listened to it all the time back in the late 70s and early 80. living in northern Michigan I could pick up wls in Chicago and stations in Cleveland. Gave it to my brother last year , not sure if it still works, ill ask him next time I see him.
Got the Sony version of this type radio. I forgot it in the garage about six years ago, and it sat there,through 100 degree summers and -40 F winters. So I brought her into the house this spring and cleaned all the spiders and dirt off her, plugged her in she still works but needs a good cleaning of the band selector and rheostats, if I could just get the damn buttons off so I can get at the insides.
You have another solution in your past video: NOS ex-soviet germanium transistors manufactured in early 90's are really cheap on epay. I have used both small signal and power and works perfect. Re-biasing is fun and also works fine. Nice radio and fun video as usual!
I've seen those "mini-modules" in GE offerings from around 1963, through 1977/78. If memory serves, poor connections and corrosion between what would now be called either the motherboard", or possibly the "backplane assembly" and those modules plagued those radios. I believe a corrosive wave solder flux may have been the problem. We used to run a blast of tuner and control cleaner between the two boards, gently tapping would often expose intermittents, (I often saw evidence of factory touch-up near many of those modules) Another vice which GE had was in overmodulating the pre-amp and driver stages, to the point that clipping could be easily detected (damn near a sawtooth wave could be seen driving the collectors). Many competent shops refused to service GE products, and often used the "can't get parts" excuse. By the way, a very masterful job of of troubleshooting, and best of luck with the re-biasing and PNP Silicon switch-over.
This set likely has more in common with the Zenith multiband sets in the "Royal" series then a solid state T.O. The T.Os have more bands and more features, plus they have a built in power supply rather then needing an external one, not to mention they all have a tuned RF amplifier stage as you mentioned. I'm not sure if the ones from the early 1960s had it but my T.O 7000 has a squelch and a BFO, and a turret style band switch assembly.
I'd say that from a consumer perspective, and external power supply is far superior to an internal one. They are much easier to replace, and have the potential to be much safer, and have the appliance completely isolated from the mains.
Lots of work to rebias the amp, but an interesting engineering project. Since you're not keeping it original, I would have replaced the amp board with a PAM8403 module. They are 5V, 3W class D (stereo), and cost less than $1. No more future electrolytic or transformer issues, and lots less distortion.
Might need to add a resistor in series with the thermistor to reduce the bias pull-up (lower the bias voltage). Otherwise you might end up dissipating too much current through either your bias transistor trying to pull the voltage down, or the thermistor trying to pull it back up... These days they'd probably just use a silicon diode (or two) to accomplish the bias offset. Maybe you could just stick a silicon diode in between the 9v rail and the x-fmr C.T. instead of the overly complicated bias circuit silicon is not so sensitive to temperature?
1965 and G.E. is still using "BC" instead of AM? That's a little odd. I noticed even in the Sam's there was a mixture of the two designations, sometimes BC sometimes AM. Maybe they thought the "sophisticated" world radio user would be more comfortable with BC.
Hey Shango! I have a RCA Strato World pretty much like this one. It has 3 SW bands, but bands 1&3 barely get a signal on full volume, and it sounds really low and distorted, you can't even understand what the locutor is saying. What could it be? Transistors? Bad caps? I want to be sure I can fix it before spending all that bucks on a schematic. THANKS!!
Indeed, it has a multi-contact switch rotary band selector that scares me. I better find a professional around my area (i'm from argentina), thanks for replying! It's a RJM68E by the way
I am. Looking to buy an ac DC multi band radio that' has good tonal quality. I ve been to Goodwill stores all over the country and had no luck finding. My dream radio is the Zenith Royal 7000. I will never find one of them unless I pay five thousand dollars for it. No luck at garage sales either
Camera shake and constant movement is NOT a desirable effect (contrary to modern, popular TV show directors). It completely ruins what might otherwise be a very good production. Use a tripod, or nearly any other method of stabilization. Thanks for the effort though.
