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  • #10659
    garykuster
    CVRS Member

    Hi All, I just purchased a floor model radio (by accident looking at an antique table with my wife) It was love at first sight and I’m having trouble finding out any information about the radio (year etc.)
    It is manufactured by RCA Victor Company Montreal, The model # is C8-16 and it’s called “Globe Trotter” AM/Shortwave. I have included some pics below. The cabinet has a good amateur restoration, but it only hums and crackles when I adjust the knobs. I try to collect only Canadian built radios and have several wood and many Bakelite radios, but have never tried to restore one. I have basic electronic skills and can tell a resistor from a capacitor and can decipher a schematic diagram but that’s about it . I would love to find a schematic diagram for this radio as a starting point as I’ve read that most radios of this vintage will need to be “re-capped” and I thought I would start there. I would love to have some guidance from any members located around Montreal if possible.

    Thanks in advance, Gary Kuster

    • This topic was modified 5 years, 10 months ago by garykuster.
    #10663
    Sterling Spurrell
    CVRS Member
    #10664
    Alistair Thomson
    Forum Participant

    I couldn’t find a schematic in pacifictv nor here at CVR, but radiomuseum.org has the goods, including a parts list.

    https://www.radiomuseum.org/r/rca_victor_c8_16.html

    Non-members are allowed a limited download, so you can get the gen there without joining.

    #10665
    Sterling Spurrell
    CVRS Member

    The link I post is good for t8-14 c8-15 and c8-16 ac receivers

    #10666
    garykuster
    CVRS Member

    Thanks for all the help and links. I was able to download the schematics and parts list without a problem. I’m going to order the capacitors on the parts list, try to Identify them and replace them one by one.
    I will have to find a place with a tube tester in the hood as well. I just spent 3 hr’s watching how to videos covering the basic function of the various parts and how to replace the capacitors, so wish me luck!
    Thanks again for the links!
    Regards, Gary

    #10667
    garykuster
    CVRS Member

    Sorry, forgot to ask this question. The only physical damage visible, is a cut cable that looks shielded. Is that likely the antenna? I took some pics of the cable. (The cable is hard to see, but it’s on the left side sitting on a very short tube) On the Radiomuseum site, I was unable to find my model radio, but found an optional turntable available for it at the time. I doubt the cut wire would have been for that as there is no 110 V. additional power supply on the chassis for a turntable. Has someone put together all the capacitors in kit form that can be purchased for this radio? Or do I take the replacement parts list and go shopping.

    Thanks again, Gary

    #10668
    garykuster
    CVRS Member

    Sorry file size was too large. Strike 2

    #10672
    Les Dickson
    CVRS Member

    Hi Gary. At the radiomuseum website model C8-16 has the schematics shown at https://www.radiomuseum.org/r/rca_victor_c8_16.html.
    I think your radio is not actually called a Globe Trotter. RCA Canada has three ‘Globe Trotter’ models that I know of:
    CDN rca-victor 1935/36 Globe Trotter T5-2 5 tubes
    CDN rca-victor 1939/40 Globe Trotter A20 5 tubes (which I have)
    CDN rca-victor 1939/40 Globe Trotter A20E 5 tubes
    That’s according to the radio museum web site.
    Also, it’s my understanding that it’s never a good idea to plug in an old radio to see if it works without first doing some investigation and remediation because it can cause some serious damage.
    Good luck!

    #10673
    garykuster
    CVRS Member

    Thanks for the info Les. Once I started reading about tube radios and watched a few tutorials, I realized turning it on as is could cause all sorts of damage and possibly fire. I’m now thinking ( until I actually know what I’m doing), It may be better to start with something a little smaller and straight forward. I have been collecting radios for years and think I’ll try my luck with one of my Philco Transitone Model 49-504’s that looks to be in excellent condition. It did play when I bought it last week (along with 3 other Philcos and the Globe Trotter), but now has died completely. Is this a better choice for a first foray into repairing,re-capping a radio? By the way, The floor model does say “Globe Trotter” on the dial, so I’m sure that’s the correct name. Now that I’m retired, I think this may be a fun hobby and much cheaper than restoring classic cars! Here are some pics of one of the Philcos.

    Regards, Gary

    #10677
    Les Dickson
    CVRS Member

    Gary, good to know that the radio actually has ‘Globe Trotter’ on the dial. It gets confusing when titles like that get used on different models. Northern Electric has many ‘Baby Champ’ radios for example.
    Good luck with the transitone. My only advice is in regard to the loctal style of tube (7A8 14A7 14B6) if you don’t remove them properly you can cause damage.

    “look for the bump at the base of the tube. Then go 180 degrees AROUND the metal tube-this is where you start rocking. In effect, you’re pushing force is directed at the bump on the other side of the base. DO NOT grab the glass envelope-just the base! GENTLY rock back and forth while GENTLY lifting and the tube will quickly and easily come out (most of the time). You’ll never go back to your old methods once you discover the correct way to remove Loctal tubes.”

    the above is from antiqueradios.com

    #10678
    garykuster
    CVRS Member

    Les, You predicted my next question precisely! I had never seen a “loctal” type tube before. One came out likity, but the rest would not bulge. I carefully pried from underneath the bump and eased the rest out. No bad sounds, so hopefully I didn’t damage anything. It looks like it has been repaired in the past as it seems to have some newer components. (see Pic) I can Identify most of what I’m looking at, but in the last pic, there is what looks like a yellow wax blob with 2 wires coming out of each end. Below the blob, there is a huge resistor (compared with the rest) and does the replacement have to be that huge as well? I want to replace it along with the other resistors and capacitors. On another topic, one of the first things I will likely need is a good meter. When I fixed cars for a living, we used Fluke meters. Is there one type or brand better than another for working on old radios?
    Sorry about the torrent of questions, but I’m really enjoying this…

    • This reply was modified 5 years, 10 months ago by garykuster.
    #10684
    Alistair Thomson
    Forum Participant

    The “big yellow blob was a capacitor and it seems to have see better day! Below it is a 220 ohm resistor, high-ish wattage. The parts list should tell you what the watts are (looks like about 4 watts), and no, the replacement will be a good deal smaller with the same wattage.

    The electrolytic caps will almost certainly be foo-bared and will need to be replaced, along with iffy-looking power resistors. Look for charring on the resistor and/or in any surrounding close metalwork which would indicate over-heating of the resistor.

    When you get to testing, you’ll need to plug in the speaker otherwise most of the circuitry won’t work. That is a field coil speaker: the magnet is powered by a coil which is also used in the power supply for smoothing – at a high voltage, so be VERY careful when going anywhere near the speaker or its connections when powered up.

    #10685
    Alistair Thomson
    Forum Participant

    Actually, my mistake – I was thinking abut the C8-16. This Philco has high voltage on the transfomer primary, but the speaker and its wiring is safe.

    #10686
    garykuster
    CVRS Member

    Thanks Alistair, for the insight. The ‘yellow blob’ with 2 in and 2 out does not look melted or damaged. My best guess is it’s 2 capacitors stuck together with wax or something. I still need to find the schematics and parts list for the 49-504 and I used up my downloads from radiomuseum on the C8-16 for now. Once I have that, I’m hoping I can figure it out. What I thought was my other 49-504 with a slightly different dial turned out to be a 46L that works. Same chassis, different tubes, so I can’t swap them over to test them. I also noticed ,the 46L is bakelite and the 49-504 is plastic! Otherwise, they look the same. Love finding out the little differences. looks like Philco changed from Bakelite between ’46 and ’48. Too cool. I didn’t have any Philco radios until last week and now have 4 ! Hopefully, what I learn on the first one will help with the other 3 that all work, but have issues. Cool repair sticker on the 46L…

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    #10689
    Dan Walker
    CVRS Member

    You do indeed have a Globetrotter C6 16. They are very nice radios, as I restored one about three years ago.
    Your cabinet is in very good condition so it won’t need to be stripped.
    When I got mine it was in bad shape, and that is part of the challenge and reward of doing these radios
    I would not suggest it to be your first restoration , do the Philco first.
    I can suggest a book on radio restoration, that many others have suggested.. it is” The elements of radio”
    by Marcus and Marcus. It is good reading at a layman’s understanding.
    Here are some photos of the one I used to have.
    You can buy your capacitors at ”Just Radios”.
    good luck.
    Dan in Calgary

    • This reply was modified 5 years, 10 months ago by Dan Walker. Reason: Add a comment
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