found a few receivers, tube radio and various tubes for free. can i get help figuring them out?

[ranjith]

Hello All,

The local dump in town here has a recycling center where people drop off stuff they dont want anymore and while i was there I picked up couple receivers: a Kenwood KR-4600, Pioneer SX-3600 and a low-powered Rotel. Also picked up a Marantz Model 5000 tape deck, Stromberg-Carlson tube radio and a cardboard box of 106 vacuum tubes. I just finished counting and labelling the tubes. I dont really know what i have on hand in terms of their value, use or etc. 95% of the tubes are Realistic Lifetime Tubes and the others are Westinghouse. The various ones in realistic boxes are labelled most of them have "Japan" printed on them and the rest are either Britain or Canada. 97 of the 106 tubes are boxed and look like they have never seen daylight. some are tiny some are rather large.. Im gonna guess and say theyre unused. Some models I see are 6JM6A, 12DQ6B, 6KN6, 27GB5, 17AX4GTA, 3AU6, 15DQ8, 6LE8, 6LJ8, 6S4A,4B27, 12FX5, 6GB5, 6JM6A, 6AX4GTB and well i dont have the patience to write them all out. does any of it seem worth anything at all?

The tube radio seems very old and was caked in dust. I managed to clean it quickly and snap a couple pics. Can it be used as a stereo amp? Is it worth the effort to hold onto it to get it restored in the future? or is it just garbage and not worth anything? I have zero experience with tube amps. I have been gaining interest and been reading about tube amps online and lurking on here mainly. Unfortunately i have no money to spend on even the most basic of tube amps currently so was wondering if this tube radio was worth holding onto. I will try to upload a couple pics, please let me know if the pics dont work properly.

Thanks for any help!

[Clipped and Shorn]

What you have pictured is a basic old AM tube radio, which if you knew what to do, could likely be made to work, hopefully the "electromagnetic" loudspeaker is intact, but even those can be repaired. If you could work on it yourself it might be fun to fix, but probably not worth having professionally restored. This does not really have much potential as an external amp from what I can see. The glass tube pictured is the rectifier. Looks like maybe an old metal 6L6 for the output. As for the other tubes, you never know about them, they need to be tested. Old radio repairmen often put bad tubes in the boxes out of which came the new replacements. I didn't notice any sought after or valuable audio tubes in your short list, mostly older tv and radio tubes. We would need to see the whole list or a pic of all the tubes with numbers on boxes to tell if anything is worth getting tested as potential audio amp application. Sometimes the tube in a box could be different than the number on the box. Bad or weak tubes can appear fine visually. It might be fun to see a pic of the underside of the radio chasis. There are always radio collectors and tube hunters out there who might buy this stuff from you "as is", thus helping in your quest to save up for equipment you want, but don't expect too much, then again, you might be surprised.

c&s

[Daddy Dee]

great find. congrats.

I think the old radio would be pretty cool restored. It's not a big complicated project relative to some.

If you could get access to a tube tester, the tubes have some potential resale value, I'd think.

[ranjith]

thanks for the answers.

the electromagnetic speaker thats attached to the tube radio visually looks to be in prime condition. unfortunately the power cable was snipped off and so i couldn't just plug it in to see if it would turn on. I'll take a shot of the underside, it looks a bit messy. And maybe im wrong but I think i see a few capacitors that look to be made of paper? I remember reading somewhere that these are a fire hazard.

I could make up file listing all the tube types. I went through each box and the tube inside is exactly what it says on the box outside. I dont know anything about tubes and yeah visually they look pretty new. Here is the deal, i searched about the Realistic Lifetime Tubes and apparently Radioshack still warranties them till this day. If i can somehow test these and a few, if not all, turn out to be bad I can contact Radioshack for warranty. They supposedly replace them with some chinese tubes which in turn are not warrantied. So either way I'd have a working tube. Ultimately it'd be real cool to have it work. I've had experience in designing, building, and testing circuits (nothing complex, mostly control systems and such). I am decent with a soldering iron and if I can learn about how to fix this I would definitely give it a shot. If the tubes turn out to be not very audio amp worthy I could always give them away to whoever wants any of it. I just dont wanna say pay shipping without knowing if they even work. Are there any good sites, tutorials or books to learn about vacuum tubes and related circuitry/uses?

If it doesn't work I could always sell it although I have no idea what it'd be worth, if anything at all. I found a tiny brown label on the underneath of the chassey and it lists the tubes it uses: 80, 6F6, 6F5, 6H6, 6K7, 6A8 and another 6K7.

The other two vintage receivers that i also picked up seem to work well. I threw them in with an old technics cdp i had lying around and matched with my KG2. Kenwood is more powerful but the Pioneer sounds much nicer. Its warmer and the low end is much smoother. However, theres a slight problem with the pioneer. the left channel both in A and B seem to be crackling/noisy. does this sound like an easy fix?

[Clipped and Shorn]

Check to see if the old tube radio has been messed with aside from the plug being snipped off. Does all the wiring underneath seem to be intact. Trace things out in case there are any obvious signs of broken wiring or tampering. Blow off dust/cobwebs with your compressed air. Can you tell if someone perhaps replaced some parts with what looks like newer parts? Is there a fuse somewhere in the circuit where the AC power cord goes in? Is it blown? Can it be replaced. This radio would have had an old fashion two prong AC plug which you can still get. You should get hold of a Variac. Doesn't need to be a big one. The last one I got was on eBay. When you feel confident that there are no booby traps or obvious shorts or whatever waiting for disaster, you could plug it into the variac and gradually give it some voltage, see if a pilot light goes on (if it has one), figure out which is the on/off switch (could be contained in the volume control (?)). The only tube you would see start to glow would be the 80. Be prepared to turn off even the low voltage if you detect a problem or smell something like burning. If things are ok, you can gradually bring up the voltage more and see if the thing starts to warm up and make any audible hum through the speaker. Eventually and gradually if you bring it up to near operating voltage and no parts have totally failed you will hear something out of the speaker, if you attach a ground wire and some makeshift antenna to the designated terminals, you might tune around and hear a station. When we see a pic of underneath, recommendations could be made to replace certain nasty old capacitors. All the tubes for this radio are readily available and not particularly expensive or anything, I might even have some lying around if you can figure out which one(s) have gone bad. You might even have some in your stash. Don't mess with anything you don't understand, especially any adjustments that have to do with the "RF", that means any little screw adjustments on parts you don't understand that have to do with tuning in stations etc. We would also like to see a pic of the front to tell what kinds of switches you have, you never know, some of these old radios even could tune in short wave. Sometimes you can dig up information online, even old schematics for the particualr model. There are many radio restorers and enthusiasts out there who may know something, you can learn by googling.

c&s