you lost me there ........
I insisted on confirming +/- PSU voltage on amp pcb , as a way to confirm both PSU functionality and GND existence on amp pcb itself
regarding leaving just one pair of mosfets connected for tests - that's way of simplifying things - and leave connected just ones necessary for proper amp functionality ; as I'm not having direct experience with PD pcbs , I can't be certain which position(s) of output mosfets is crucial , without enclosed both ref. schematic and decent pcb pictures
so - what to do first ......... disconnect all (output mosfet's) source resistors ( lift one resistor end from pcb .... or desolder source wire -probably easier in your case) ; that way all mosfets are out of circuit , so we can check functionality of input side .
gnd both inputs .
power amp on - check functionality of input LTP - that means - measure all important nodes of input LTP CCS , and voltage across input JFet drain resistor
please attach (or link to ) ref. schematic with results
if you do that - I can write exactly what and how to measure
then we can proceed
I insisted on confirming +/- PSU voltage on amp pcb , as a way to confirm both PSU functionality and GND existence on amp pcb itself
regarding leaving just one pair of mosfets connected for tests - that's way of simplifying things - and leave connected just ones necessary for proper amp functionality ; as I'm not having direct experience with PD pcbs , I can't be certain which position(s) of output mosfets is crucial , without enclosed both ref. schematic and decent pcb pictures
so - what to do first ......... disconnect all (output mosfet's) source resistors ( lift one resistor end from pcb .... or desolder source wire -probably easier in your case) ; that way all mosfets are out of circuit , so we can check functionality of input side .
gnd both inputs .
power amp on - check functionality of input LTP - that means - measure all important nodes of input LTP CCS , and voltage across input JFet drain resistor
please attach (or link to ) ref. schematic with results
if you do that - I can write exactly what and how to measure
then we can proceed
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all the time - until it's ready to sing
??!
with or without mosfets in circuit ?
even if I can't see anything wrong on your pictures , you're th eone who need to check every connection
insert Ampermeter in each rail (one by one ) , between cap bank and pcb and measure - without mosfets you'll have up to 20-30mA , no more
with mosfets - increased for Iq
Hi ZM. You mean ground the inputs all the time until it is ready to sing?
The board vibrates with and without the mosfets connected. It wasn't there before.
So, one probe on the negative rail and one probe on the negative of the amp board pcb to test the ampere and then repeat the same for the positive rail, is this correct?
yup
that's confusing .......
yup
find some tutorial on web , how to make basic measurements
look here , for instance :Basic Car Audio Electronics
look at right menu - Digital Multimeter
you mean - one pcb is drawing 0,54mA from pos and and 0.21mA from neg rail ?
with JFets in place , just mosfets removed from circuit ?
as I said :
with JFets in place , just mosfets removed from circuit ?
as I said :
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