Old radio

[grenadier]

I took apart an old Admiral TV some months ago that I picked up off of craigslist so I could harvest the AC flyback transformer.

http://i.imgur.com/UmrUZ.jpg

I knew this thing had a radio, but what I didn't know is how amazing it was. It's a hollow state AM, FM, FM Stereo receiver with AFC. It has a phono input and 4 ohm stereo output.

http://i.imgur.com/KNdOt.jpg

I plugged it in not expecting anything to happen, and nothing did happen. I left it plugged in and 10 minutes later it turned on. Odd.

Expecting mains hum I turned up the volume. No hum. In fact I got a clear FM stereo signal and this thing had no antenna attached. All the stations came in loud and clear on both AM and FM, and FM stereo. Can't believe the filter cap is still good after all those years. The pots are clean too; no scratchy sounds when turning them. Although the speakers are all nostalgic, I'm probably just going to toss them and use better ones.

Oh, and the circuitry is perfect. http://i.imgur.com/iFwXQ.jpg

Anyone know what model this is and does that person have some schematics? Antiqueradioforums failed me here.

[kevinkr]

Never a good idea to just plug in old tube hardware without checking and then reforming the caps, but you probably got lucky this time..

Those speakers probably have alnico magnets and there are plenty of people who may be interested in having them here or elsewhere. You might want to wait a bit before you decide to chuck them..

Bearing in mind the available output power of a couple of watts it is likely that most inexpensive modern drivers are not going to have the requisite efficiency to work well with the amplifier in this set up. I'd just make a couple of nice boxes for them..

[grenadier]

Actually I already chucked them, kinda copied that text from antique radios forums .

As for the reforming, my variac was and still is busted, so I took a gamble. After all, explosions make electronics fun.

[kevinkr]

Explosions in vintage gear like this can be terminal.. Some parts just can't be replaced economically..

Shame you got rid of the speakers already, but some of the more ambitious full range drivers in appropriate boxes (FR forum) might work pretty well. On reflection dumping those old speakers is probably a small loss, let's hope so anyway.

You should talk to planet10 about what is possible with one of these vintage flea power tuner amps.

I'd fix your variac or alternately a lamp wired in series with the mains will soften the blow of initial power application particularly in the event of a fault and prevent damage to irreplaceable parts like the power transformer. (There is a thread somewhere around here about ballast lamps which is what we are talking about here, a 25W - 200W incandescent bulb depending on the item being worked is pretty near ideal.)

[grenadier]

That could work, but there must be a better way to soften that blow because a cold tungsten lamp has a low resistance and allows quite a bit of power through at first. If nothing else, a large rheostat could work.

[the_manta]

- Admiral (brand) Continental Radio & Television Co.
- Admiral "The Kirtland" SMDU3000 Series Stereophonic Theatre;
23" b/w TV with US FCC standard VHF turret & UHF dial tuner, FM/AM-FM stereo multiplex radio, stereo phono.
- 1965

There was a whole product line. There were: The Creighton, The Hillsboro, The Kirtland, The Welton, The Westmont

Sadly I don't have any schematic

Very very sad you don't have the original speakers anymore. I hope you don't use that wonderful console set just for scavenging parts.

One request, could you take some good additional photos from the front, please ? That would perfect.

[DF96]

Inserting a normal incandescent lamp in series with an old radio when first switching on is a recognised standard procedure - known as a lamp limiter. Although the cold resistance of the lamp filament will be low it will very quickly heat up if the radio takes excessive current. The initial peak is not the problem. It is sustained leakage current which will blow electrolytics. A shorted mains filter capacitor may explode if full mains is applied but a lamp limits the current. kevinkr's advice is correct.

An alternative is to use a variac, but this is more expensive and does not limit the current.

[grenadier]

The CRT's heater was burnt; I had no other choice but to scrap it.

The speakers' cones were pretty much rotted out too, so there wasn't much left there anyway.

[the_manta]

Oh, that's a real problem, I know.
Those old CRT's are incredible hard to get. They take so much space (and cation) in storage rooms that nearly every repair shop has thrown them out.
Hope you got some nice parts.

[grenadier]

I managed to get quite a few nice tubes and inductors out of it, as well as that schmancy radio. For $0 and a trip across town it wasn't a bad deal.