Good day,
I got a SA 600D in, U107 burnt. Removed and cleaned up PCB. All FETs tested ok. found burnt U107 to be a TL072 from another thread (link below), which I've wired in temporarily .
Powered up, unit powered up ok, god PS FET gate drive, rail and reg LV supplies. I do have R-R oscillation on the output FETS, however I don't have audio.
I have a square wave on pin 1 of U107 and a somewhat rounded square wave at pin 7, U107. I have good HS and LS FET gate drives. In the last pic attached there's a trace that connects to R141 and runs under U107.
I cant seem to find where this trace connects to. If I send a strong 45hz sinewave into the RCA inputs I can see an attenuated sinewave at R141. Tracing around the preamp/XO section, seems to be working correctly. The class D PWM generation and driver section also appear to be working correctly.
I've also tried connecting this trace to pins 2,3,5,6 of oU107 without success. I still don't have audio at the output speaker terminals.
https://www.diyaudio.com/community/threads/sundown-sae-1500d.377950/page-4
Anyone got a pic of this area without U107 or can tell me where it connects to?
I got a SA 600D in, U107 burnt. Removed and cleaned up PCB. All FETs tested ok. found burnt U107 to be a TL072 from another thread (link below), which I've wired in temporarily .
Powered up, unit powered up ok, god PS FET gate drive, rail and reg LV supplies. I do have R-R oscillation on the output FETS, however I don't have audio.
I have a square wave on pin 1 of U107 and a somewhat rounded square wave at pin 7, U107. I have good HS and LS FET gate drives. In the last pic attached there's a trace that connects to R141 and runs under U107.
I cant seem to find where this trace connects to. If I send a strong 45hz sinewave into the RCA inputs I can see an attenuated sinewave at R141. Tracing around the preamp/XO section, seems to be working correctly. The class D PWM generation and driver section also appear to be working correctly.
I've also tried connecting this trace to pins 2,3,5,6 of oU107 without success. I still don't have audio at the output speaker terminals.
https://www.diyaudio.com/community/threads/sundown-sae-1500d.377950/page-4
Anyone got a pic of this area without U107 or can tell me where it connects to?
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