replace pcb (one previosuly mounted) and replace SIT
later test them both , once when you have one functioning amplifier
later test them both , once when you have one functioning amplifier
Will do. Probably next Tuesday or Thursday. Really looking forward to hearing the amps. So close.
...... to get newly made mains NTC pcbs
.....
ha, it took me at least 5yrs , to engage brain and draw them ....... ordering is trivial afterwards

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have to wait 'till next Thursday , to get newly made mains NTC pcbs
bummer
🙂
Like those heatsinks - where did you get these?
it's nothing else than new guts in old amp - it was Papa's Koan (M)2 , amp for living room
more in my blog Papa’s Koan (M)2 , an amp for living room | Zen Mod Blog
it was heavy as on pic , now few kg more
more in my blog Papa’s Koan (M)2 , an amp for living room | Zen Mod Blog
it was heavy as on pic , now few kg more

ZM, do you recommend mounting the PCB to the heatsink or the riser plate is fine? Need to know the rise dimensions to cut to. Thanks in advance
please clarify
simple way of mounting you can see on start of the thread , and later
you can also use L or T bracket
so , I need clarification what you mean with "riser"
simple way of mounting you can see on start of the thread , and later
you can also use L or T bracket
so , I need clarification what you mean with "riser"
that's SMD 100nF-200nF , filter cap for 7805
if you're able , you can solder any small 100nF cap there , on SMD pads
it couldn't go Dodo because of overheat (nothing is heating it) , neither you have critical voltage
maybe you got blob or splash of solder there which did go Puf! , taking cap with it
worth trying to troubleshoot , minding is there steady 5V at 7805 output
if yes , hall chips are alive
if you're able , you can solder any small 100nF cap there , on SMD pads
it couldn't go Dodo because of overheat (nothing is heating it) , neither you have critical voltage
maybe you got blob or splash of solder there which did go Puf! , taking cap with it
worth trying to troubleshoot , minding is there steady 5V at 7805 output
if yes , hall chips are alive
that's SMD 100nF-200nF , filter cap for 7805
if you're able , you can solder any small 100nF cap there , on SMD pads
it couldn't go Dodo because of overheat (nothing is heating it) , neither you have critical voltage
maybe you got blob or splash of solder there which did go Puf! , taking cap with it
worth trying to troubleshoot , minding is there steady 5V at 7805 output
if yes , hall chips are alive
So, replace blown/melted filter cap, reinstall board, reconnect SIT, and measure voltage difference between p2 (ground) and p3 (output) of 7805? That should be 5V.
I can leave input and outputs unconnected during the procedure, right?
Thanks ZM.
pretty much like that
in fact , no need for mounting pcb at all , for 5V check
you can leave mosfet in and no SIT , just temporary short pins 3 and 4 of opto , with thin wire
if you have some nice 7-8-12V PSU , connect just that to GND and positive rail , and check 7805
in fact , no need for mounting pcb at all , for 5V check
you can leave mosfet in and no SIT , just temporary short pins 3 and 4 of opto , with thin wire
if you have some nice 7-8-12V PSU , connect just that to GND and positive rail , and check 7805
got NTC pcbs today 🙂
LEDs , tiny input wires , final cooking ........ then rocking!

LEDs , tiny input wires , final cooking ........ then rocking!

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