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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sat 04, 2017 1:17 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Okay I'm going to sit down and buy the capacitors tomorrow, is there anything else I should buy to replace? I would like to get this record player to sound and function to the best of its ability


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sat 04, 2017 1:31 am 
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Joined: Feb Sat 06, 2016 1:47 am
Posts: 2148
Location: Santee Calif. 92071
Sheaving or shrink tubing to cover capacitor leads. The hum is the old filter capacitor. That would be the main Concern. The other capacitors should be replaced just good insurance for a dependable long lasting amp.


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sat 04, 2017 3:20 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 4064
Location: Boston, MA USA
You do not have to replace any of the capacitors under the chassis. The two black tubular capacitors are not paper, they are polyester film and will be fine. You only have to replace the three electrolytic capacitors inside the cardboard-covered can on top of the chassis. The current standard value for an 80 uF capacitor is 82 uF, and for 20 uF it is now 22 uf.

-David


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sat 04, 2017 4:51 pm 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Okay thanks, so I'm only replacing the capacitor on top? I was kinda hoping there'd be more to replace only because the bass is pretty crappy, would replacing something solve that or is that something I have to deal with?


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sun 05, 2017 12:23 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Hotwax wrote:
Quote:
okay am i replacing the other black capacitors underneath? or do i really just need to replace the large on that sits on top. also can i remove the cardboard while its still soldered together and just put the replacements inside the cardboard cover (as long as they all fit? or do i have to actually desolder the electrolytic capacitor all together


1. Yes, replace the 2 black Sprague caps. Clip off the lead (of one end only) near the
body of the capacitor. Then just bend the cap around to see the microfarads/voltage printed on
the body. Take photos as you go, so you have the original reference points where the
caps go in the circuit.

2. The filter capacitor can (C1) on the outside of the chassis may be
a metal body covered with cardboard. If the can is metal, then you have to saw off around
the cylinder and pull out the electrolytic "guts". Then you re-stuff the can with new caps.
You can search on ARF for tutorials/topics on that.

3. Yes, you can use a capacitor with a HIGHER voltage. To save space,
use the 160 Volt for your original 150 Volt caps.

4. Modern capacitors will not be available in exact values for your 80 and 20 uF
filter caps. You can sub a 100 uF for the 80, and a 22 uF for the 20.

There is a 120 uF electrolytic at this parts house:
You may as well buy the rest of your caps there, pretty good prices.
https://www.westfloridacomponents.com/J ... apxon.html


The website you recomended does not have any 80uf (82) or 20uf (22) capacitors does anyone know a website where i can buy all of my electronics?


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sun 05, 2017 3:53 am 
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Joined: Feb Sat 06, 2016 1:47 am
Posts: 2148
Location: Santee Calif. 92071
Go here for all the capacitors you need. Do have the 80 MFD 160 volt. And the 22 MFD 160 volt. Still say to replace the other smaller value capacitors too while your at it.

http://www.justradios.com/cart.html


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Sun 05, 2017 11:22 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 4064
Location: Boston, MA USA
Tonyv773 wrote:
Okay thanks, so I'm only replacing the capacitor on top? I was kinda hoping there'd be more to replace only because the bass is pretty crappy, would replacing something solve that or is that something I have to deal with?

Remember, the capacitor can on top has three capacitors in it, all of which need to be replaced. But nothing will help the bass. This is not really a high fidelity phonograph. The amplifier is capable of only a couple of watts per channel, and the output transformers are really small. The speaker enclosures are too small for much bass. That said, many phonographs produce much better bass and a much fuller sound if you play them with the lid closed.

-David


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Mon 06, 2017 5:45 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
dberman51 wrote:
Tonyv773 wrote:
Okay thanks, so I'm only replacing the capacitor on top? I was kinda hoping there'd be more to replace only because the bass is pretty crappy, would replacing something solve that or is that something I have to deal with?

Remember, the capacitor can on top has three capacitors in it, all of which need to be replaced. But nothing will help the bass. This is not really a high fidelity phonograph. The amplifier is capable of only a couple of watts per channel, and the output transformers are really small. The speaker enclosures are too small for much bass. That said, many phonographs produce much better bass and a much fuller sound if you play them with the lid closed.

-David


So just to make sure is that a total of 5 capacitors? (3 in the cardboard electrolytic capacitor) and 2 in the body?


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Mon 06, 2017 6:05 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 4064
Location: Boston, MA USA
No, you do not need to replace any of the capacitors under the chassis. Just the three in the can up top.

-David


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Thu 09, 2017 4:21 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Would 47uF be okay for a replacement 50uF or should I go higher?


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Thu 09, 2017 5:01 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4064
Location: Boston, MA USA
47uF is fine.

-David


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Feb Wed 15, 2017 10:52 pm 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
I just realized I needed a 80uf and not a 50uF, my capacitors came in today and I have two 22uf and two 47uF, what should I do for the 80uf capacitor?


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Mar Wed 07, 2018 1:56 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Update:
So I have not posted in a while, but shortly after purchase of the replacement electrolytic capacitors, I replaced them, and started using the amplifier. The amp works great, but I get bored and always want to make things better. What else should I replace? Does anyone have any recommendations as to replacement speakers (one of mine has a small amount of rust) Also do you think I should just invest in a modern Vacuum amplifier and retrofitting it in place with higher output speakers. (not drastic, I dont want my needle jumping, just for a little better sound quality)


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Mar Thu 29, 2018 5:21 am 
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Joined: Sep Fri 02, 2016 10:07 pm
Posts: 34
Bump


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 Post subject: Re: Magnavox Micromatic 1sc-237 Amplifier Restoration help
PostPosted: Mar Thu 29, 2018 3:48 pm 
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Joined: May Sat 06, 2006 4:03 am
Posts: 2957
Location: ZIP 23831 South of Richmond, VA 25 miles down the pike.
Tony, it is what it is. You can't make a silk purse out of a sow's ear. As mentioned you are getting maybe a couple watts each. If cranked up it will distort. Many of these 3-tubers were made and many people got and still get satisfaction from playing their records. Sounds like you are destined for the much higher end equipment for enjoyment. Don't tear it up, sell it and put your money in the better stuff.

Bill J.


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