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  #1  
Old 08-23-2026, 10:02 AM
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Motorola vt71

In the vt71 Motorola there is 2 300v 120uf capacitors was wondering if those caps can be replaced with 100uf with no working problems being these old sets already have the so called 20-30% built in. If this can be used is there a difference between any other capacitor and a disposable camera electrolytic capacitor rated at 100uf 300-330v

Last edited by timmy; 08-23-2026 at 10:38 AM.
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Old 08-23-2026, 10:40 AM
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Do you have any way to check the true value of the 100 mfd capacitors? Most electrolytics are allowed +50% -20% from what I have seen. The total B supply current is 110 milliamperes so I don't think there would be a problem.
Like you mentioned, these sets have a pretty wide tolerance in parts.
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Old 08-23-2026, 10:41 AM
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Quote:
Originally Posted by Zenith26kc20 View Post
Do you have any way to check the true value of the 100 mfd capacitors? Most electrolytics are allowed +50% -20% from what I have seen. The total B supply current is 110 milliamperes so I don't think there would be a problem.
Like you mentioned, these sets have a pretty wide tolerance in parts.
I measured the cap it’s at 102uf
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Old 08-23-2026, 10:45 AM
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I have 2 450v 470uf in there now which was supposed to be temporary but I never changed them I think it’s time to get them out befor it takes out the b+ diodes.
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Old 08-23-2026, 11:07 AM
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Or the ballast!
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Old Yesterday, 10:01 AM
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It'll probably work fine. B+ may be slightly lower, but line voltage today tends to be slightly higher so it'll probably be a wash.

Depending on physical size I might be concerned about camera flash caps having poor life rating in continuous filter duty, but without seeing a datasheet it's hard to know... Not many people run electrostatic sets for more than 30 min every few weeks so even if life isn't long it may not matter.
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