| homertooties |
Here are some pics of the pioneer there are parts missing out of the board which i have done to test,i took all the relays out because the rapid clicking got annoying after a while.
The 2 grey resistors are okay,1.2 k and 1.8 k these drop the volts from 39 vdc to 30 vdc ,+ and - ,then they are drop again for preamp stages through the psu at the side of the 2 15000mf psu caps,preamp rails being +16vdc and - 12.5vdc.
there has been a repair on this amp before there are 4 teapo caps 10mf 100v which have been put in a zener diode by the side of the left psu cap was bust im guessing it is 33v because there is another on - rail.
All of these parts are in the supply to the left of the main psu caps,apologies for rubbish pics.
I really need some help on this one as soon as you press the direct button on front panel amp stays on.............
Any help would be fantastic. |
|
|
| ACD |
| If you post the pics it will be a lot easier :D |
|
|
| homertooties |
this time maybe |
|
|
| homertooties |
 |
|
|
| homertooties |
 |
|
|
| homertooties |
 |
|
|
| homertooties |
 |
|
|
| Gold_xyz |
| O.T. It uses the function macro to focus better ! ;) |
|
|
| homertooties |
 |
|
|
| homertooties |
 |
|
|
| homertooties |
 |
|
|
| jaycee |
| It could be me but it looks like a channel's heatsinks and output devices are missing. |
|
|
| homertooties |
| Hi there yeh all parts i put in are just pushed into board not soldered they were taken out for testing cheers |
|
|
| XEAGLEKEEPER |
Homertooties
Look carefully at the two large PSU caps. Notice how the plastic labels have shrunk down ,a good indication that they are running to hot probably leaking soon if not already. |
|
|
| homertooties |
| Hi there many thanks for reply ill rip the caps out now and solder a temp pair in....cheers |
|
|
| 4fun |
Hi,
I have opened many (even new) Pioneer amps that have caps looking like that, only little short plasic film. Look for bulging and leaks instead.
Edit: And age makes them increase their esr. |
|
|
| homertooties |
| Hi there still does it with other replacement caps ,however when i take the 15volt reg and 2sc tranny out (low voltage supplies it doesnt do it,so im gonna put those 2 parts back in and disable there output from feeding the board many thanks for reply |
|
|
| ilimzn |
| The caps are fine... but you are missing the output stages of the amps (transistors and heatsinks)! |
|
|
| keith721 |
| I recently repaired a wall-wart transformer for a friend's D-Link router. The problem was three bad electrolytic caps - all Teapo. Are the tops bulging on any of them? |
|
|
| homertooties |
Hi all finally fixed the pioneer a605 r
Went through the motions of replacing many parts which have now been put back as was ,unbelievable fault,got this amp cheap due to repair of low power supplies,however due to many hours of trying to source fault,did a test on the volume ribbon cable seven wires,did a continuity test from 1 t0 1 and got 1 to 7 alarm bells ringing:bigeyes: some plank in past had put this cable in wrong way round so now the amp was not getting + and - 15vdc up the front end,unbeleivable,detatched pioneers crappy socket and soldered each cable through board,:D :D :D
Hey presto amp fixed the old saying springs to mind things are not always as they seem
Many thanks for input members...... |
|
|
|
