• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Sony TA-F570ES does not turn on!

Kochumvk

Kochumvk

New Member
Hello,
I have a Sony 570ES integrated amp bought on Ebay. Amp reached in a bad shape.

Problem:
When I turn on the power button, it remain orange for some 10 seconds then momentarily turns green (1/4 second) and returns to orange. What might be the cause?

Note:
When the amp reached me, the heat sink has came off the mounting screws and it bent the final stage transistor leads. However I believe their integrity is intact. Power supply caps have good solder joints.

I have the service manual from here.
 
Register to hide this ad
Not familiar with the amp, but as a guess, sounds like the amp is going into protection. Give me a moment to track down the service manual.
Do you have a multimeter? Are you comfortable taking voltage measurements on a live unit?
 
With the amp powered off/unplugged, suggest you diode test the output transistors.
Also download the service manual from hifiengine, need to register, it's safe, no spam etc...

Using diode function on most multimeters, need to diode test transistors on the heat sink Q312, 313, 309, 359, 362, 363 (I think)

Nice graphic from markthefixer, need to test 6 combinations as per red/black probe orientation.
Expected results are either 650mV (500-750mV) or OL/Open Circuit.

DiodeTest.JPG

Welcome to AK, let the fun begin...
 
mbz said:
With the amp powered off/unplugged, suggest you diode test the output transistors.
Also download the service manual from hifiengine, need to register, it's safe, no spam etc...

Using diode function on most multimeters, need to diode test transistors on the heat sink Q312, 313, 309, 359, 362, 363 (I think)

Nice graphic from markthefixer, need to test 6 combinations as per red/black probe orientation.
Expected results are either 650mV (500-750mV) or OL/Open Circuit.

View attachment 1090377

Welcome to AK, let the fun begin...
Click to expand...

Thank you for the quick help. I don't have a multi-meter in here. But I will order one one Amazon right away.
I will report back day after tomorrow with the test results.
 
Amp turns on if A/B jumper between main board and tone board is removed.
With the jumper it goes to protection mode.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom