how to revive a first generation Olympic 447 portable transistor radio

this radio is housed in a hinged split case. the hinge is at the bottom and the radio splits open right along the center inline with the knobs. it's easy to open so you can replace the batteries. no tools are needed to get inside.

pic 2 is of the radio opened up. the radio runs off 9vdc. it has two battery connectors but both are wired in parallel. now is a good time to see if your radio works at all. do not exceed 9v input to the radio. you risk damaging some VERY hard to find transistors. this radio will power up with 6v-9v. you can use a regulated power supply or a 9v battery and alligator clips.

look at the old battery connectors coming out of the radio. on the connector at the end of the cable, the terminal at the very end (not where the wires come in to the connector) is the positive terminal. apply power, turn the radio on at full volume, and tune around. get anything? any sign of life is good. it's possible your radio may play loud, in that case back down on the volume control.

your radio should have a pictorial diagram inside like the one in pic 3. it may be of help here. on a humorous note, the pictorial diagram shows the transistors in transistor sockets. the actual production model just re-used the tube sockets.

are you getting lots of hash and noise but nothing intelligible? is the radio right next to a computer or lithium battery charger? those two things can generate plenty of RF noise on an AM radio. relocate the radio and try again or shut off the possible noise sources. try again.

get anything now? if your radio picks up anything, that's a good sign. tinny, weak, or distorted audio we can fix. if your radio is totally dead you may need to do some simple checks.

take a multimeter and check for continuity from the positive battery terminal to the metal radio chassis. the radio should be switched on for this test. like many early transistor radios, this one uses positive ground. you should have continuity. if you don't, you need to find out why.

look at the volume control. the power switch is built in. it's got two terminals grouped together. those are the power switch terminals. check for continuity here. you should have continuity when the radio is switched on. if you don't, your power switch is bad and that would cause a dead radio.

if you have a totally dead radio, there is still hope but you may want to consider the fact that your radio may have issues beyond the scope of this instructable.

next up, we get inside.

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Re-new a vintage radio and restore its gleam.

This is a 1950ish Firestone radio alarm clock. I found this at a flea market and got an excellent deal. I did not know if it worked or not and I didn't care, I saw potential in it right away. When I got it home, I plugged it in to see if it worked or not. It made a humming noise right away. Not a "radio" noise, but a mechanical noise. I found that that was the clock running.
After about 1 or 2 minutes all the sudden I heard radio noise, a quick tune got many different talk radio station. It sounded awful, but, none the less, it still worked. So for now, I decided to simply clean and polish the entire thing to bring it back to its original (as original as possible) glory...Look the unit over carefully. Check the knobs as well, those are the first to come off. Some knobs have set screws. Most pull off with a little force...
Find the screws that putt the radio guts out. Mine has three located on the bottom. after I remover those I pulled the entire radio out and had to unplug the clock cable from the main radio tray. After that I removed 2 nuts holding the clock in place via a bracket. Whenever possible I find it a good habit to place the screws nuts and bolts back in the holes after you remove the parts you are removing.
I also removed the metal face plate and glass dome from the clock face by bending the small tabs out, on the back of the clock face.

After I removed all the inside parts its time to move on...

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how to revive a sylvania reflex circuit transistor radio

to get inside you need to remove the back cover of the radio. this is also how you'd open it up to replace the battery. many old transistor radio are setup like this were you pry open a lid to get inside. once inside you will find the circuit board (chassis) and the schematic.

note the battery holder. is it corroded from an old battery left in it? if it is, replacements can be found online. radio shack used to carry 9v clip on terminals but i'm not sure if they still do.

the circuit board is held in the plastic housing by 1/4" hex head bolts. note the two i'm pointing at in pic 4. you will be removing those two and the two on the right edge near the battery connector. no need to remove the remaining two as all they do is hold the tuning capacitor in place.

once the screws are out, you can carefully lift the board out. be careful with the speaker leads.

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