ok jfets q217, q215, q115, q117 are pulling 29 volts at idle the rest are at 24 volts at idle at the gate. ok correct me on the right terminalogy q112, q113, q212 and q213 are the transistors the work with the fets pullin 29 volts and is there a problem with 4 volts difference wait i guess there would be thats what is shutting down the tl494 right? Any suggestions would be greatly apprieated
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All of the outputs are bipolar transistors, not jfets. The B688 and D718 transistors are the outputs. There are 6 outputs per channel.
Bipolar transistors don't have gates. Their terminals are the base, collector and emitter.
The term 'pulling volts' doesn't mean anything. I'm not sure what you mean.
Bipolar transistors don't have gates. Their terminals are the base, collector and emitter.
The term 'pulling volts' doesn't mean anything. I'm not sure what you mean.
You need to write in complete, precise language if you want others to understand what you're trying to convey. For example, what does 'with remote voltage applied bipolar' mean?
The smaller transistors function as drivers, predrivers and as part of the differential amplifiers. They consist of both NPN and PNP bipolar transistors.
Which terminals did you measure the voltage on?
The smaller transistors function as drivers, predrivers and as part of the differential amplifiers. They consist of both NPN and PNP bipolar transistors.
Which terminals did you measure the voltage on?
Sorry perry was using the battery post
doing it the right way middle leg of the fets there is a ten volt difference
q217, q215, q115 q117 26 volts
the rest are at 36 volts
Remote voltage is with amp powered up at idle with the + and - and the remote hooked up no speakers or nothing hooked to the rcas
black on non bridged speaker termial red on middle leg of the bipolar transistors
doing it the right way middle leg of the fets there is a ten volt difference
q217, q215, q115 q117 26 volts
the rest are at 36 volts
Remote voltage is with amp powered up at idle with the + and - and the remote hooked up no speakers or nothing hooked to the rcas
black on non bridged speaker termial red on middle leg of the bipolar transistors
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For the channel with the 200 series parts (Q2..), there had to be an error. The three outputs of each part number (d718, b866) have their center legs directly connected by large traces. The voltage on those legs must be identical. If they are not, you have a burned trace or the voltage changed between the time you measured one then the next. Re-check them.
yeah
Well now I think whatever was making the amp go into protection has stopped being intermintent, I have +10 volts on the drain of all the z44's and +.50 volts on the gate, but the amp quit going into protection, the z44's are getting very hot so can't leave the amp on to long to try to figure out what is causing them all to get hot
Well now I think whatever was making the amp go into protection has stopped being intermintent, I have +10 volts on the drain of all the z44's and +.50 volts on the gate, but the amp quit going into protection, the z44's are getting very hot so can't leave the amp on to long to try to figure out what is causing them all to get hot
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OK pulled the bipolars out and got voltage readings
3 d718's right side of amp
base collector emitter
-22 +22 +.03 all three same
3b688 same side
-22 +22 +.03
left side d718
+22 +22 .00 all three
b688
+23 -23 .00 all three
amp is still in and out of protection with bjf out of amp
Looks like left side 718's are getting wrong polarity on the collector.
would it be a diode? Plus the voltage on the emitter on the right side?
3 d718's right side of amp
base collector emitter
-22 +22 +.03 all three same
3b688 same side
-22 +22 +.03
left side d718
+22 +22 .00 all three
b688
+23 -23 .00 all three
amp is still in and out of protection with bjf out of amp
Looks like left side 718's are getting wrong polarity on the collector.
would it be a diode? Plus the voltage on the emitter on the right side?
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