First off, MOST caps do NOT need replacing!!
Caps last for years and years and years and years
and actually may be one of the factors in your equipment's 'Vintage" sound!!
ONLY REPLACE CAPS WHEN YOU SEE SIGNS OF DETERIORATION
OR
if you find a number of the same cap needs replacement in various cards
(then replace them all)
First let's look at what bad caps look like!
If you see something like the above, where the rubber or plastic vent cap is puffed out
go ahead and replace it.... if a bunch of the same value and make of the cap are going
bad, then replace them all...
I'm finding that most 440's, MM1000's, MM1100's and MM1200's are now at the age
where a lot of the electrolyics in the Audio Cards are begining to leak
and go bad.
This may show up a a loss of over-all level, a loss of low frequency signals,
cards not working correctly and other probelms.
So in the older Ampex machines I recommend you replace the following caps:
RECORD CARD: C28 10uf 25 volts (replace with 10uf 50 volt caps)
REPRODUCE CARD: C13 and C8 50uf 50 volt (replace with 50uf or 47uf 50 volt caps)
Note these are AXIAL caps - the wires are connected to each side of the cap!!
Note that all electrolytic caps are polarized - they MUST be installed
in the correct way or they may explode or fail right away - so make SURE
that you replace your caps correctly !!!
If you are not sure what you're doing, hire a tech to come in and
replace your caps - or bring your cards over to your tech's shop
to get done right !
You'll need the following tools:
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Soldering Iron and Solder
Jameco Electronics part # 229673 $ 59.95 each
get Solder at your local Radio Shack
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Solder "Sucker"
Jameco electronics part # 19166 $ 4.95 each
++++++++++++++++++++++++++++++++++++
Small cutters and small needle-nose plyers