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#1
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Majestic 130-A
Hi Guys, Just new to this forum..Need Info on a Majestic 130A radio.
I have a schematic from nostailaire but the size is very small. This set is in pretty good condition except it don't have any speaker. I have restored 20 or so old tube radios, but nothing like this. First of all, it has all the tubes. One bad 24, the rest check 60% or better. How do you get at the cap's? I call them bathtub type, you know the cans thats soldered to the chassis. Are they electrolytic or the paper ones in a can? This is a TRF type of set. How do you get at the IF and RF coils? there all in a tank like can. Does anyone know what Transformer voltages I should have. I know the tubes have 2.5VAC fil. voltages. If anyone has any tips on this beast, I would welcome any help. I just ordered an electromagnitic speaker on ebay for a Majestic radio, hope it works and will work with my set. Thanks to all, Gary |
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#2
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Got any pictures? You don't usually have to get at the coils in the cans.
Since it has a power transformer, there is most likely some type of filter caps. I'm working on a model 25 right now, iirc it had 3 electrolytic caps in it, a 8 and two 10mfd. What part of PA are you in? |
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#3
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looking at your schmatic, looks like 3 lytic caps in it, all are 2 mfd. Marked as A, B, and C on the diagram.
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#4
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I am in Lewistown..Haven't figured out how to post pix on the fourm yet.
Do you have a Majestic 130 A? |
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#5
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No I have a model 25 I'm currently working on.
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| Audiokarma |
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#6
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I would suspect that the filters are in a metal can full of tar. That's how a lot of manufactures did it in the late '20,s. If it is a trf set it will not have any IF transformers nor will it have a oscillator coil or local oscillator. Different type of circuit.
Terry |
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#7
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Ok guys, I got the Majestic 130-A playing..But, I can only get the two local stations.
And I have to hook a wire to the Detector grid cap to get the stations to come in. They are clear and strong, however the volume control does nothing. I injected a 1300kc signal at the ant. and get nothing. All them coils seem to ohm out alright. How are you supposed to troubleshoot this set when all the tubes are supposed to be in there up right position??? Need help, Gary |
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#8
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The volume control adjusts bias on the first two tubes so until those stages are working the control won't do anything. With the antenna on the detector grid, you get sound, so the last 24 tube and the audio output stage are OK. Now move your antenna to the grid of the tube just before the detector and ditto on each tube in turn working back towards the first stage. Where you lose your signal look for trouble in that stage: voltages OK? Coil continuity, condensers not shorted, resistors OK, etc. The 24's are OK upside down, but the 45's you want to be careful of as their filaments could sag and touch the plates and adios 45. But you don't need to play the radio upside down. Locate the stage you want to troubleshoot via the grid test, turn the set off, turn over, and check all components in that stage.
__________________
Reece Perfection is hard to reach with a screwdriver. |
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#9
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Thanks Reece, I will try what you suggested.. Have you ever worked on this model Majestic? The chassis weighs 60lbs. All tubes test good, and all filter caps have been changed, also all out of tollorence resistors changed.
I see what you mean about the volume on the schematic. Thanks for your intrest, Gary |
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#10
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Never had the pleasure to work on a Majestic, but I am building up my muscles for when I do.
These TRF's follow the same pattern, one amplifier after another until you get to the detector, so several stages will be essentially the same to trace out. Somewhere in there is something open or miswired. Does it look like anyone was in there before you?In your underchassis picture, looks like something burned down in the lower left corner?
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Reece Perfection is hard to reach with a screwdriver. Last edited by Reece; 02-14-2012 at 07:32 PM. |
| Audiokarma |
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#11
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Your right, there was a dogbone resistor there and it was burned apart.
It goes to the trimmer cap. to the ant. I can't find it anywhere on the schematic. So I stuck in a 400 ohm in there. I think your exactly right about something being missed wired. I think somebody was in there before me. This radio in sitting my brother in laws antique funiture store. I would like it to work better but am amazed it sounds so good! Gary |
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#12
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Looks like a 1930'to 32' manufacture..years a good looking radio
heavy as all get out,..diffently a boat anchor.,how much does your Brother-n-law wants for it$$... ![]()
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