So I received a kx800.4 yesterday and maybe some components are missing from the preamp section. A few op amps. I'll use the other side to match the missing parts. The issue is it's just flashes the protection light then fails to power up?
Post several pictures of amp, one overall and one with and w/o preamp board.
Is there any current draw when the amp attempts to power up?
Check the outputs with an ohmmeter if you haven't already. If the outputs check okay, remove main board and inspect solder around outputs, header for preamp.
The +/- 12 volt near the preamp board generates a lot of heat, check around this circuit for shorted zeners,transistors,caps and check solder.
Is there any current draw when the amp attempts to power up?
Check the outputs with an ohmmeter if you haven't already. If the outputs check okay, remove main board and inspect solder around outputs, header for preamp.
The +/- 12 volt near the preamp board generates a lot of heat, check around this circuit for shorted zeners,transistors,caps and check solder.
All the componts check ok and the soder joints look good. Just those three componts are broke off at the board. Q22, Q23, U4. There are heat spots on the underside of the board around those two missing transistors.
So I ordered all the missing parts to the amp. Does anyone know how to get it out of protection? When u connect power to it. The protection light comes on then shuts off. And it remians drawing .2amps of current.
Ok thanks perry I'll check it now. The power led doesn't even light up. Just protection. It's strange.
1. .005vdc.
2. .023vdc
3. .006vdc
4. .001vdc
5. 0
6. 0
7. 0
8. .697vdc
9. 0
10. .773vdc
11. .751vdc
12. .782vdc
13. .125vdc
14. .112vdc
15. .095vdc
16. 4.134vdc
2. .023vdc
3. .006vdc
4. .001vdc
5. 0
6. 0
7. 0
8. .697vdc
9. 0
10. .773vdc
11. .751vdc
12. .782vdc
13. .125vdc
14. .112vdc
15. .095vdc
16. 4.134vdc
Just finished the output section. Audio on every channel. I replaced u3-u4-u13. U purchased enough to do them all. The transistors q22-23 bd139-bd140. All four pnp transistors on the underside. So it's now working. One thing it didn't shut off when I removed the remote voltage?
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