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Thread: Old radio - is this line-powered?

  1. #1
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    Old radio - is this line-powered?

    Saw this advertised locally as "Old AM Radio". The seller claims the output valve is a 6V6 (not normally found in a line-powered radio, I don't think they work well at such low anode voltages). Also, there appears to be a tweeter, which I would imagine is a luxury you would not have found in line-powered "All American Five" radios.

    But I can only see one (very beefy) transformer in the photo, instead of the expected two - power and audio output transformers.

    What are we looking at here?

    -Gnobuddy
    Attached Thumbnails Attached Thumbnails valve_radio_1200x900.jpg  

  2. #2
    Old Timer Tom Phillips's Avatar
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    That big Transformer is definitely the power transformer. The output Transformer would be much smaller and I suspect it's mounted underneath the chassis. Note the speaker wires coming out of the hole in the back of the chassis.
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  3. #3
    Stray Cap DrGonz78's Avatar
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    Yup definitely mounted inside the chassis. I also see Rogers branded tubes so it makes me think that might be the brand. Figure out the model # and you might even find it at this site here...
    Nostalgia Air: Rogers-Majestic Corp. Ltd. (Canadian)
    When the going gets weird... The weird turn pro!

  4. #4
    Senior Member Enzo's Avatar
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    And how did we determine the anode voltages were low? That power transformer can put out whatever voltage they wind it for, and a 300v B+ sounds perfectly reasonable in that unit.

    I agree the OT is likely under the chassis, it needn't be large for this table radio. No larger than a Champ OT or a Fender reverb transformer.
    Education is what you're left with after you have forgotten what you have learned.

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    Quote Originally Posted by Gnobuddy View Post
    Saw this advertised locally as "Old AM Radio". The seller claims the output valve is a 6V6 (not normally found in a line-powered radio, I don't think they work well at such low anode voltages). Also, there appears to be a tweeter, which I would imagine is a luxury you would not have found in line-powered "All American Five" radios.

    But I can only see one (very beefy) transformer in the photo, instead of the expected two - power and audio output transformers.

    What are we looking at here?

    -Gnobuddy
    just because there is a 6v6 does not mean that is what belongs there. People will sometimes fill sockets with whatever fits so they can show it turns ons( and sometimes burns up).

    nosaj
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  6. #6
    g1
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    I take it you do not have the unit and are just looking at the ad? Or can you post a pic of the front?
    Chances are that a schematic could be found.
    That added 1/4 inch jack looks pretty iffy, not sure what that would be for? Ext. antannae do not usually use 1/4" type connectors.
    Maybe someone was using it as a guitar amp.
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  7. #7
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    Quote Originally Posted by Tom Phillips View Post
    That big Transformer is definitely the power transformer. The output Transformer would be much smaller and I suspect it's mounted underneath the chassis. Note the speaker wires coming out of the hole in the back of the chassis.
    I did notice the speaker wires coming out the back, but then again, the way that big black transformer is mounted, all the connections to it are also under the chassis, so I didn't know what to think. Basically, I have zero experience with valve stuff of this vintage, so not enough background knowledge to draw the right conclusions.

    Thanks for your input!

    -Gnobuddy

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    Quote Originally Posted by Enzo View Post
    And how did we determine the anode voltages were low? That power transformer can put out whatever voltage they wind it for
    Sorry, you misunderstood me, I was thinking out loud that the presence of a 6V6 output probably meant that the black transformer would be a power transformer, i.e. this wouldn't be line-powered. But the next mystery was, where the heck was the OPT?

    -Gnobuddy
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    Quote Originally Posted by g1 View Post
    I take it you do not have the unit and are just looking at the ad?
    Correct. The seller seems to know very little about the radio; he hacked into it and added the 1/4" jack in the attempt to turn it into a guitar amp, but he says his attempt was unsuccessful.

    An old radio with at least one botched bit of work on it. Not a likely restoration project, but if the price was low enough, maybe worth it for the transformers and vintage speakers, maybe even the chassis and wooden case?

    -Gnobuddy

  10. #10
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    Quote Originally Posted by Gnobuddy View Post
    Correct. The seller seems to know very little about the radio; he hacked into it and added the 1/4" jack in the attempt to turn it into a guitar amp, but he says his attempt was unsuccessful.

    An old radio with at least one botched bit of work on it. Not a likely restoration project, but if the price was low enough, maybe worth it for the transformers and vintage speakers, maybe even the chassis and wooden case?

    -Gnobuddy
    I wouldn't pay more than $10 for it.

    nosaj

  11. #11
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    Trannies, case, chassis? Prolly. Speakers? Erm, not so much. $10 sounds good to me! Unless seller can verify that it WORKS, not "powers up & tubes light up."

    Justin
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    Quote Originally Posted by Justin Thomas View Post
    Trannies, case, chassis? Prolly. Speakers? Erm, not so much. $10 sounds good to me! Unless seller can verify that it WORKS, not "powers up & tubes light up."

    Justin
    Fix it up into a ghostbox add some steampunk and sell it for $800. They're really crazy

  13. #13
    Senior Member Enzo's Avatar
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    You know, if we had the make and model, it would go a long way towards answering these questions. Schematics are available.

    Yes, the 6V6 might not belong there, but I disagree with the assertion they are not found in line operated sets. In fact that is about the only place I'd expect them. 6V6 is not designed for series string heaters. They would be powered by a transformer.

    Oh wait, by "line powered" you mean hot chassis. To me a power transformer model is also line powered.

    Never mind.
    Education is what you're left with after you have forgotten what you have learned.

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    Quote Originally Posted by Enzo View Post
    You know, if we had the make and model, it would go a long way towards answering these questions. Schematics are available.
    I'm not being coy - as I said, the seller doesn't seem to have much information about the radio he's selling. It does say "Viking" in the ad, but there is no year or model number. A little Google sleuthing turned up this: Canadian Eaton's Viking Tube Radio

    The radio in that link is clearly not the same model, but it seems that "Viking" was a house brand for a chain of east-coast Canadian department stores called "Eaton". I would guess that "Vikings" were sourced from whatever manufacturer happened to be lowest bidder at the time.

    I used Google images to try and find anything similar looking, to see if I could pin down a year, manufacturer, or model number. So far, no luck.

    Google also turned up this Kijiji ad for another Viking radio. I have a suspicion this is either the same, or at least a similar, model to the one shown earlier (back view only): https://www.kijiji.ca/v-art-collecti...ationFlag=true

    At any rate, the seller wants much more than I think this thing is worth, so that's probably the end of that, unless he experiences a bit of a wake-up.

    Quote Originally Posted by Enzo View Post
    Oh wait, by "line powered" you mean hot chassis. To me a power transformer model is also line powered.
    Sorry if I used the wrong terminology. Yes, I meant "plugged into the wall, but no power transformer".

    -Gnobuddy

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    Quote Originally Posted by Justin Thomas View Post
    Speakers? Erm, not so much.
    You may be right, but I was thinking "little single ended 6V6 guitar practice amp". Maybe the bigger (elliptical) speaker would handle that job.

    -Gnobuddy

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    Quote Originally Posted by nosaj View Post
    Fix it up into a ghostbox
    I had to look that up. Wow, you're right, people who believe in that sort of thing are really crazy!

    -Gnobuddy

  17. #17
    Senior Member Enzo's Avatar
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    https://www.samswebsite.com/en/photo...earch&s=Search

    Don't know if any of these relate to yours or if they are even the same Viking, but Sams has a bunch

    Some Vikings here:
    http://www.nostalgiaair.org/Resources/

    Also AES has old radio schematics, but I see no Vikings. But a call to them might net you information on where to look.
    Education is what you're left with after you have forgotten what you have learned.

  18. #18
    Old Timer Tom Phillips's Avatar
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    You could also ask the seller for more information, additional detailed photos etc.
    Doesn't hurt to ask.

  19. #19
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    Enzo - thanks for the links!
    -Gnobuddy

  20. #20
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    Tom Phillips - Yeah, I might do that tomorrow. Thanks for the suggestion!

    -Gnobuddy

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    Beware. If the seller tried to hack it, then it obviously means he tried to power it up. Depending on what he actually did to it, he may not have replaced the old paper/wax insulation DC blocking capacitors. They are very frequently leaky (Frequently as in 'almost always, you can bet on it.'). This may mean at least the 6V6 output tube may have been run with B+ on the grid through a high value resistor, essentially zero grid bias, so it may be dead.

    If the 6V6 died a violent death, then it may have taken one or both of the transformers down with it.

    I have plenty of experience with old tube based radios. When people have hacked into a radio like this, wires dangling everywhere, then I would expect that *none* of the components still works, and be positively surprised if they do. Maybe none of the circuitry under the chassis is still there...
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  22. #22
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    Quote Originally Posted by Thoriated Tungsten View Post
    Beware. <snip>
    Thanks for the warning. You've certainly given me something to think about!

    (Cute username, by the way!)

    -Gnobuddy

  23. #23
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    +1 on leaky paper caps. Most of the old radios I used to work on pretty much needed every one replacing. With this kind of thing I like to pay just enough so that in the worst case I'll always get something out of it of value. A bit like an electronics-store goody bag.
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