Search found 9 matches

by DavidBelgium
Mon Sep 21, 2015 6:39 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

andyfras wrote:
DavidBelgium wrote:Somebody a spare lying around ?
I can offer an exchange PSU - I like a challenge.
Andy,

Can you give me a quote P&P included.
It's not mine, so I have to check with the owner if he is willing to spend any money on "old" hardware
by DavidBelgium
Fri Sep 18, 2015 7:30 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

I'm now back looking at the primary side and that's for me unknown terrain given that the datasheets of regulator KA1M0680 are very little detailed on the functioning. . Looked at the old U1 that I replaced when I changed the caps. There was a short between Fbk and VCC and as result of that, the in...
by DavidBelgium
Sun Sep 13, 2015 8:21 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

Thanks Alan

The link was dead however I found another one thanks to the name of the file

https://www.usbid.com/datasheets/usbid/ ... n-4104.pdf
by DavidBelgium
Sat Sep 12, 2015 8:45 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

Andy, I removed ALL diodes at the secondary and checked them each with a lamp and a PSU in forward and reverse direction. None of them was broken. I also injected the respective output voltages by means of an external lab powersupply and measured at the same time the current consumed and the charge/...
by DavidBelgium
Thu Sep 10, 2015 10:52 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

Check the rest of the voltages and that should show which diode is shorted. After some months leaving the board in a dark corner of my desk, I reattempted repair of my PSU ORTP-831 I have these voltages: Expected Real 3,3 < 0,1 5 1,36 8 2,18 12 3,55 15 3,42 17 4,72 22 6,94 30 9,1 So I presume D10 a...
by DavidBelgium
Sun Nov 23, 2014 12:29 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

All, It's not entirely dead, it is alive but voltages are very low and too low to start even anything. When I attach my scopemeter, I see on cathode of D1 vs chassis every 175-200ms a 25V dc peak. So I presume the coil is energized at primary side http://i58.tinypic.com/2upy9oo.jpg [/img] Output vol...
by DavidBelgium
Fri Nov 21, 2014 10:51 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

Another attempt... plugged it in and now I get just over 12v over C9 but still no power... According to the datasheet, the start threshold of V1 must be between 14 and 16v ; which is higher than what I measure. :x :x Mains voltage is 217 V, which is at the low side and voltage over the big cap is 30...
by DavidBelgium
Fri Nov 21, 2014 10:16 pm
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

Hi Andy D2 was ok but it is new one soldered in after I couldn't trace the error R1 was ok and R3 is also Polarity of all caps were ok and I had replaced them all. No old one was left on the board. However, I removed the new V1 chip and found out there was an almost short between pin3 and pin4 ; app...
by DavidBelgium
Sat Nov 15, 2014 11:50 am
Forum: Bugs
Topic: PSU Repair - Latest Information
Replies: 264
Views: 127976

No idea what is wrong with this board ORTP-831

Hi, A topfield PVR 4010 plus died with some smoke according to my father in law. When I inspected the board, I couldn't detect any bulged or burnt components. I read this topic carefully and understood it would be necessary to replace all caps nevertheless. I replaced ALL electrolytics with panasoni...