Author Topic: Magnavox AstroSonic - No AM/FM, Loose wire  (Read 1203 times)

MagMan

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Magnavox AstroSonic - No AM/FM, Loose wire
« on: June 08, 2016, 11:58:15 AM »
Hi guys, I'm hoping you can help me with a problem. I've just completed a recap on a AstroSonic and everything sounds great except I'm not getting an AM/FM signal. There's a wired soldered to the tuner I'm not quite sure about. I've recapped dozens of AstroSonics and have never seen this before, possibly a repair made to it at some point. Where should the other end of this wire connect to? There's no mention of it on the wiring diagram inside the cabinet. Please see the picture.  Any help would be most appreciated, thanks.

Harbourmaster

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #1 on: June 08, 2016, 04:36:54 PM »
Looks like its soldered in near one of the trimmers... where is the other end connected?
-- Aloha, Ken

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MagMan

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #2 on: June 08, 2016, 04:48:55 PM »
I found it loose in the cabinet, I can't figure out where the other end is supposed to go.

Harbourmaster

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #3 on: June 08, 2016, 05:28:02 PM »
Well it's not "supposed" to be there in the first place so no telling where it was connected!



-- Aloha, Ken

No Console Left Behind!

Larry H

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #4 on: June 08, 2016, 06:09:56 PM »
Someone probably tried to hook up an external FM antenna there.  Remove the wire.
--Larry

MagMan

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #5 on: June 08, 2016, 06:37:55 PM »
Could this wire be related to my problem with no AM/FM, maybe an attempted repair?

Larry H

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #6 on: June 08, 2016, 07:37:58 PM »
Could this wire be related to my problem with no AM/FM, maybe an attempted repair?
That's possible.  If it was an attempted repair, it wasn't successful.
--Larry

electra225

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #7 on: June 08, 2016, 08:08:24 PM »
I agree with the others that the wire should probably not be there.  Do you have a schematic?  If so follow what it tells you.  If not, now is a good time to get one to troubleshoot your AM-FM.  I would then see if the antenna for one or both bands is disconnected or non-existent.  Good luck.
If it ain't broke, call me.  I can break it....

MagMan

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #8 on: June 08, 2016, 10:20:01 PM »
Thank you everyone for the input, I'm going to remove it and get the schematic. 

Thanks again, Kent

MagMan

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #9 on: June 15, 2016, 05:19:57 PM »
Hi Guys, I appreciate everyone's help as I chase down the issue with no AM/FM signal. I'm at least getting static now whereas before both AM/FM were dead. Here's a Newbe question, I want to test the transistors pictured below, do they test the same way as 3 lead transistors? Do I interpret the readings the same way? I'm not sure about the fourth lead. Thank you very much!

Motorola Minion

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #10 on: June 17, 2016, 01:12:11 PM »
The fourth lead goes to the case-sheild, since its an RF transistor. It is likely a germanium transistor and the diode setting on a DMM will read .2-3 volts forward and infinite in reverse.
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Dave

MagMan

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Re: Magnavox AstroSonic - No AM/FM, Loose wire
« Reply #11 on: June 17, 2016, 04:41:34 PM »
The fourth lead goes to the case-sheild, since its an RF transistor. It is likely a germanium transistor and the diode setting on a DMM will read .2-3 volts forward and infinite in reverse.

Thank you Dave, attached are the test results. Would you please review and let me know if there's anything that's cause for concern.


Ronald

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1967 Magnavox Imperial Astro Sonic Home Theater with Remote
« Reply #12 on: January 13, 2017, 07:29:55 PM »
I just bought a 1967 Magnavox Imperial Astro Sonic Home Theater with Remote Control the (Agean-Model) in Solid Hard Wood in Pecan Finish that has the 2-Front Slidding Door's that hide the TV!! So here is my Trouble!! The AM/FM Stereo & Turntable Work's!! But the (25"-TV) don't work but the back of the Picture Tube light's Up!! This Came from a non smoking home & the Wood does not have a Scratch on it anywhere!! The 2 Button Phantom Remote Control also work!! So where do I start to get the TV back & up running again? It hasn't been plugged in for year's!! I was born in 1951 & grew up with these & want to keep it Original!! So where do I start on getting the TV Working again? This is the 300 Pound Console!!
Can anyone help me figure where to start at on the TV?