Author Topic: fluke 343a -15V power failure for help  (Read 578 times)

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Offline daisizhouTopic starter

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fluke 343a -15V power failure for help
« on: December 11, 2020, 12:08:37 pm »
A fluke 343a is being repaired and found that the -15V power supply has disappeared
Found that Q21-SM 4144 transistor is damaged.This is a transistor made by Motorola.Can't buy now

I want to know what should I do? Is there a replacement model

Thanks for help. thanks
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Offline wn1fju

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Re: fluke 343a -15V power failure for help
« Reply #1 on: December 11, 2020, 04:58:08 pm »
The -15V is an auxiliary supply whose components do not seem terribly crucial.  The reference for the 343a, fortunately for you, is in the +15V supply.  I would think you could get by with just about any medium power general purpose PNP transistor for Q21.  Something like 50V C-E, a couple of hundred mA current and a 1 watt power dissipation.
 

Offline daisizhouTopic starter

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Re: fluke 343a -15V power failure for help
« Reply #2 on: December 12, 2020, 01:54:04 am »
Thanks for the successful repair
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