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  • #19153
    garykuster
    CVRS Member

    Hi all, just found this Canadian Rogers Majestic and gave it a good clean, 1 new tube, some new knobs and it sounds great! Normally, I would go straight to re-cap, but it’s too perfect to mess with. Did replace the burnt panel light with a led red one for fun, but it’s a little too intense at night and reminds me of the radio version of John Carpenters “Christine.” Slowly moving away from wood radios and going for Canadian plastic/ bakelite radios but not exclusively.

    • This topic was modified 1 week, 5 days ago by garykuster. Reason: wrong Carpenter
    #19161
    Ralph Spracklin
    CVRS Member

    Morning Gary

    I am assuming that this is a “ALL AMERICAN FIVE’ Radio. And I am also asuming that the tube you replaced was a 35W4. You also say you replaced the burnt out Panel light. If that panel light went out first, that is most likely the reason the tube was also lost. And if your new LED light is not drawing enough current, you will surely lose the second 35W4 in short order. Using this LED could be a recipie for further disaster!! So the correct rule of thumb, on these radios is to never use the radio if the panel light does not work, or does not draw enough current!!

    Much has been written about the filament problems related to this 35W4 Tube.

    Regards

    Ralph

    #19164
    garykuster
    CVRS Member

    Hi Ralph,
    I’m aware of the panel light situation on some/most AA5 radios, but this one is wired a little differently! It was the 12AT6 that was shot. I replaced it with a 12AT7 for now as that’s all I had in my tube stash and it was listed as a satisfactory replacement. This is the first AA5 I’ve seen that uses a 117volt 7 watt dial bulb. This is basically the night light bulb. To date, every AA5 that I’ve encountered had the dial light tapped off the tube heater circuit, but this one in such a way that it just uses line voltage. As a rule, I always replace the panel light(s) before bringing it up slowly on the Variac. Here’s the schematic.

    http://pacifictv.ca/schematics/philipsb2c10u.pdf

    Regards, Gary

    #19174
    Ralph Spracklin
    CVRS Member

    Hello Gary aand All

    The setup here does seem to me at least, a different approach to the usual problems caused by the panel light.(for better or for worse, I am not yet certain). So!! Sorry for my pushing on this, but asking questions on issues such as this, is how I learn, and how I get to wrap my mind around things. As to what they were thinking when they, the engineers. did things a certain way.

    However, I am thinking, and maybe I am wrong, that the use of the 7 watt bulb, and should it fail, would put extra current across the filament of the 35W4. Could it be that the filament on the 12AT6 was already the weakest point in the filament chain, and thus caused it to fail therefore saving the 35W4 from failure??? Bail me out guys, especially if I am wrong.

    Regards
    Ralph

    #19175
    garykuster
    CVRS Member

    Ralph, In this case, I think it was just the 12AT6’s time to go. The radio still played great with the old tube, but on start up, there was bright flashes at the base of the tube and then it settled down to it’s regular brightness. New tube solved that. I don’t think the burnt panel light and the damaged 12AT6 ate related. 2 separate events. You are absolutely right that burnt panel lights will hasten the demise of the 35W4 but this particular radio seems to be an exception, but I may be wrong as well. As Ralph said,” bail us out guys.”

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