how do i check a final is working

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moggy
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how do i check a final is working

Post by moggy »

Hi i have just found a mrf 454 in a old fuse box i have if i remeber it was pulled from a radio that had been crushed on the front so i asume its a worker how would i check if it is ok.
And more to the point what apps would it be used for linear i assume but to what power and is it any use keeping
Kenwood ts2000e heil studio mic
altron 12m mast tailtwister rotor
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Corblimeyguvnar
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Re: how do i check a final is working

Post by Corblimeyguvnar »

Yep amp,

http://malzev.tripod.com/comp/mrf454.htm

As for testing, I look forwrd to someone replying
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flickpot
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Re: how do i check a final is working

Post by flickpot »

I have also some that was taken from radios in the past, great to find if there working or not.
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zephyr
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Re: how do i check a final is working

Post by zephyr »

For a quick test you can use your meter set on diode test.
If you look at the transistor (pill) as a full wave bridge rectifier and test each diode in turn,
this will tell you if there is a short or an open circuit on any of the diodes.
You have to remove the transistor to do this test.
Other than that you'll have to wire a short piece of wire to each terminal and use the HFE facility on the meter, if it has one, to determine it's gain, anything higher than about 15 and it should be a working one.
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