I have an APA4300hx on the bench which powers on
All the digital displays light up but it's not producing audio on any channel.
Any help appreciated, thanks
All the digital displays light up but it's not producing audio on any channel.
Any help appreciated, thanks
I just noticed the power on led doesn't light up, only the digital display does.
So to clarify it doesn't power up, 0v accros the output transistors legs
So to clarify it doesn't power up, 0v accros the output transistors legs
Yes Perry I downloaded the manual thank you, I'll check the voltages on the TL594CN tomorrow and test the power supply
Tl594 pins read as follows, Vdc
1, 0
2, 003
3, 0
4, 0
5, 001
6, 003
7, 0
8, 012
9, 006
10, 007
11, 012
12, 012
13, 005
14, 004
15, 004
16, 003
1, 0
2, 003
3, 0
4, 0
5, 001
6, 003
7, 0
8, 012
9, 006
10, 007
11, 012
12, 012
13, 005
14, 004
15, 004
16, 003
Can't see any burnt or broken traces,
I checked the voltage on the power supply stiffening
Capacitors and they read 000v on both legs with power applied?
I checked the voltage on the power supply stiffening
Capacitors and they read 000v on both legs with power applied?
Black on the ground wire outside the amp.
Touch every solder joint in the B+ line, starting on the solder joints for the B+ terminal.
Touch every solder joint in the B+ line, starting on the solder joints for the B+ terminal.
All tests fine,
Looking at the schematic Tl594 should have 5v on pins 1 and 2, this one tested
000 on pin 1,
003 on pin 2 could this indicate a fault with the Tl594?
Looking at the schematic Tl594 should have 5v on pins 1 and 2, this one tested
000 on pin 1,
003 on pin 2 could this indicate a fault with the Tl594?
Sorry, I think I mistook the rail caps for the power supply caps, so to confirm there's 0v on the rail cap legs, caps c828, c830, c828 and c827
Hi Perry I checked the output transistors and found Q143 was shorted it reads 0 ohms accross all 3 legs, so I pulled Q143, Q144, Qi41 and Q142 to see if the amp might come out of protection or power up and it's still not powering up?
This goes back to the meter confusion. 012 and 013 were actually 12 and 13. The readings of 0v for what would have been 000 on your meter added to the confusion.
If 006 was 6v, the driver IC was producing output at that point.
What meter do you have?
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
If 006 was 6v, the driver IC was producing output at that point.
What meter do you have?
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Sorry for the confusion Perry, My Meter was on the wrong setting - now adjusted correctly.
I've edited my signature with as much info as the system would allow.
Thank you
I've edited my signature with as much info as the system would allow.
Thank you