|
|
Post by gregstv on Feb 5, 2016 2:16:43 GMT -5
Hi Guys, Has anyone had anything to do with one of these AV receivers? If I power it on the standby light flashes quickly. maybe twice per second. If I do a reset pressing Surr, exit and clear it will come on for a few seconds and then switch back to flashing standby light. I have measured all the output transistors for shorts and they are all good. Any ideas? Thanks, Greg
|
|
|
|
Post by mastertech on Feb 5, 2016 15:45:20 GMT -5
I would jumper the main power relay so it was powered all the time and then test all the regulators on the (2) regulator power boards. Do you have the schematics?
|
|
|
|
Post by gregstv on Feb 5, 2016 17:53:53 GMT -5
Hi, Thanks for replying, No I don't have a schematic for the unit. Do you know where I can get one? I have put a jumper on the mains relay that applies power to the main Transformer. Behaviour is still the same with this jumper in place. Thanks, Greg |
|
|
|
Post by mastertech on Feb 5, 2016 18:12:51 GMT -5
yes, I know the behavior would still be the same. The objective is to be able to test the regulators without the unit shutting down.
I emailed you the manual. Let me know if you got it ok.
|
|
|
|
Post by gregstv on Feb 5, 2016 21:32:17 GMT -5
Hi Mastertech, Yes the manual arrived. Thank you. I will short the relay out and do some checks on the regulators. I will get back to you shortly. Thanks, Greg |
|
|
|
Post by gregstv on Feb 7, 2016 3:11:03 GMT -5
Thanks for your help Mastertech, There were a couple of issues. First of all I purchased it of EBay faulty. Someone had tried to fix it at some stage. For some reason they changed C945 on the 1.25V supply. In doing so they shorted some tracks around the pins together with solder. Somehow they scraped away the solder mask. I also noticed that L811 was not placed and the solder had been touched. I checked the circuit and it should be there. I replaced the missing inductor and still no go. After shorting the relay again as you suggested I found strange voltage readings on the VCC. I removed the regulator board and found the ground track was blow open circuit. I repaired the track and reassembled the unit and all working well. No idea what blew the track. The only problem is I have no idea of what the original fault was. I have run it for 2 hours and no issues. I could not of fixed it without the service manual. Thank you.
|
|
|
|
Post by mastertech on Feb 7, 2016 11:39:13 GMT -5
You are welcome. Glad you got it straightened out.  |
|
