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Old 01-16-2008, 04:06 AM   #1
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Help Reviving Old Tubed Reel to Reel

I've got a Voice of Music Model 700 from 1955 that i'm working on reviving.

it'a portable s one track, record/play on 1/4" tape. it seems to work reasonably well as an amplifier when i plug my ipod into it (the irony), and tape playback seems reasonable, but i can't get it to record very well.

it's got a 5879 tube for a preamp, a 12AX7 labeled as PRE-AMP and AF AMP, A 6v6 used to drive 2 internal speakers, and another 6V6 labeled BIAS OSC.

i plan to start with replacing the 50-year old capacitors, but not sure which ones need to go. according to the parts list, there are some electrolytics, which i know i need to replace, but should I replace all the molded paper ones too?

is it just the coupling caps that are under higher stress?

anyone know where to get a play/record head?
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Old 01-26-2008, 03:24 PM   #2
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Go to www.thevoiceofmusic.com They have a lot of parts for these. http://hyperphysics.phy-astr.gsu.edu...dio/tape2.html this link has some info on recording process.I would doubt the problem is with the recording head itself,most likely something in the circuit,there is a bias signal that gets applied,as you will see in the link I gave you.
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Old 02-02-2008, 02:47 AM   #3
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Quote:
Originally Posted by milothicus View Post
I've got a Voice of Music Model 700 from 1955 that i'm working on reviving.

it'a portable s one track, record/play on 1/4" tape. it seems to work reasonably well as an amplifier when i plug my ipod into it (the irony), and tape playback seems reasonable, but i can't get it to record very well.

it's got a 5879 tube for a preamp, a 12AX7 labeled as PRE-AMP and AF AMP, A 6v6 used to drive 2 internal speakers, and another 6V6 labeled BIAS OSC.

i plan to start with replacing the 50-year old capacitors, but not sure which ones need to go. according to the parts list, there are some electrolytics, which i know i need to replace, but should I replace all the molded paper ones too?

is it just the coupling caps that are under higher stress?

anyone know where to get a play/record head?

I agree with stokes. And I'll go a bit further to say yes, replace every cap with a decent quality film cap. Check every resistor asn consider replacing any that are more than 10% off value. If the ocsillator is not working properly it will not record or at best it will record very poorly.
I've resurected a late '40's wire recorder by simply replacing the parts mentioned above. It actually had a half way decent sound for what it was....
good luck!
Marc
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Old 02-02-2008, 04:01 PM   #4
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I think i'll put in an order for capacitors and see what happens.

i'm actually glad to hear that the oscillator is so critical. hopefully that's the problem. that's an easy fix.

now to find the time...
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Old 02-11-2008, 05:51 PM   #5
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Where do you find the rubber drive belts. I have a couple of those reel to reels but all rubber and foam parts have "disintegrated".
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Old 02-12-2008, 02:01 AM   #6
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Where do you find the rubber drive belts. I have a couple of those reel to reels but all rubber and foam parts have "disintegrated".
Try terrysrubberrollers.com he does a great job on the pinch rollers,maybe he can help you with the belts or point you to someone who can.
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Old 02-12-2008, 06:54 AM   #7
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Try terrysrubberrollers.com he does a great job on the pinch rollers,maybe he can help you with the belts or point you to someone who can.
Thx. I will. I doubt though he has parts for European stuff like the old Philips recorders all of us here grew up with in the 60es.
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