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MRF455 Bias voltage

N6ADA

Member
Jan 4, 2013
7
1
13
Hello all, I'm working on an amp with MRF455 transistors. Would someone happen to know what the bias voltage should be for these? I'm reading -12v on the base keyed or unkeyed. This doesn't seem correct, but I'm not sure.

Thanks
 

If I had enough information, amp brand, model number, or a schematic I could be more helpful. Unkeyed the voltage should be ZERO volts. I am hoping that your voltage reading of -12v you just have your leads reversed. If you have -12v and you do not have the test leads reversed then maybe you have reversed your power supply.
 
The posting read as follows: I'm reading -12v on the base keyed or unkeyed.
Last I heard V means voltage.
You are correct about the quiescent currents at 80 to100 ma idle current.
 
Thanks guys. Sorry, after posting this I figured it out. Yes for class AB approximately .6 volts but adjust for correct current as mentioned. I was trying to figure out how to delete this thread :(
Thanks again!
 

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