Hi!🙂
Yesterday I experienced the tweaker nightmare. After fouling around in my cd-player (testing a clock I built for a future cd-rom project.) suddenly my Pioneer PDS 707 died.
I`ve probably had it open and modyfied it a houndred times before and it has always worked afterwards.
So I started looking for the main fuse, but it seems like it is located inside the powertrafo, soldered between two of the legs on the pcb trafo. My two year old daughter is home with me today, insisting on helping her dad, so I haven`t tried shorting these two pins or done to much measuring. 230 V mainpower and 250 degree soldering iron do not match a two year old hanging around.
I know I have 230 v after the main swich.
I measured the resistance between the two pins where I belive the main fuse to be located, to 0,5 ohm. This I belive idicates that the fuse probably is not blown?
I have also found two fusable resistors, and theese measured 8,2 ohm like they were supposed to, but I haven`t measured them with power on ( I don`t know how theese are supposed to work, high resistance when they act like a fuse?).
When I get some time alone I`m gonna measure to se if there is any voltage over the powersupply caps to see if the trafo works.
Anybody have any Idea what usually is wrong when things like this happens?😕 I haven`t much experience in foult finding.
If anybody have any idea, I would appriciate you shearing it.
Thanks
Tor Martin🙂
Yesterday I experienced the tweaker nightmare. After fouling around in my cd-player (testing a clock I built for a future cd-rom project.) suddenly my Pioneer PDS 707 died.
I`ve probably had it open and modyfied it a houndred times before and it has always worked afterwards.
So I started looking for the main fuse, but it seems like it is located inside the powertrafo, soldered between two of the legs on the pcb trafo. My two year old daughter is home with me today, insisting on helping her dad, so I haven`t tried shorting these two pins or done to much measuring. 230 V mainpower and 250 degree soldering iron do not match a two year old hanging around.
I know I have 230 v after the main swich.
I measured the resistance between the two pins where I belive the main fuse to be located, to 0,5 ohm. This I belive idicates that the fuse probably is not blown?
I have also found two fusable resistors, and theese measured 8,2 ohm like they were supposed to, but I haven`t measured them with power on ( I don`t know how theese are supposed to work, high resistance when they act like a fuse?).
When I get some time alone I`m gonna measure to se if there is any voltage over the powersupply caps to see if the trafo works.
Anybody have any Idea what usually is wrong when things like this happens?😕 I haven`t much experience in foult finding.
If anybody have any idea, I would appriciate you shearing it.
Thanks
Tor Martin🙂
Fault Finding
Hi Tor,
I was reading fast and for one second I was understanding your 2-year old was connected to the 230V leads.
Sorry, I am bit confused today. See my other post.
To give you some good advice from a experienced repairguy:
Just measure all supply voltages to see if these are OK. These cement resistors act as fuses and are a repairmans nightmare as it is very difficult to see if they are blown or not. But of course you can measure voltage before and after the resistor. 8.2 Ohm is not blown, that would give a 8 turned 90degrees, overload.
If you have a scope check for oscillation of clocks. [You did not specify which one]. Without oscillation the player won't work. Put the probe at 10x.
If voltages and oscillation are OK check the laser for burning and going up and down. Don't look straight into to beam.
If I remember right, it is a very long time ago, Japanese players first try to find focus on a stationary disc, then signal Focus OK to the µP, then start spinning to read TOC (Table of Content) etc.
If it fails on TOC reading it won't work!
Hope this helps.😉
Hi Tor,
I was reading fast and for one second I was understanding your 2-year old was connected to the 230V leads.
Sorry, I am bit confused today. See my other post.To give you some good advice from a experienced repairguy:
Just measure all supply voltages to see if these are OK. These cement resistors act as fuses and are a repairmans nightmare as it is very difficult to see if they are blown or not. But of course you can measure voltage before and after the resistor. 8.2 Ohm is not blown, that would give a 8 turned 90degrees, overload.
If you have a scope check for oscillation of clocks. [You did not specify which one]. Without oscillation the player won't work. Put the probe at 10x.
If voltages and oscillation are OK check the laser for burning and going up and down. Don't look straight into to beam.
If I remember right, it is a very long time ago, Japanese players first try to find focus on a stationary disc, then signal Focus OK to the µP, then start spinning to read TOC (Table of Content) etc.
If it fails on TOC reading it won't work!
Hope this helps.😉
You look very flashy today, Elso.😀
Tor, try to put the original clock on the player.
Are you shure your clock is fine?
Tor, try to put the original clock on the player.
Are you shure your clock is fine?
Hi!
Thanks for advice.
My problem is that the player is completley dead. No light, nothing...
The only thing I know is that I have 230v after the switch. Haven`t had time to look any more in to it yet. All though I`m by education is an engineer I have to work at the postalservice (no engineering jobs around at the moment...) and now this close to christmas they would liked me to be at work around the clock!🙂
I fear that the power transformer somehow have broken. I don`t know why though....
I know that my original clock works, but the player should power up even without a clock.
I had hoped that it was the main fuse that were broken, but measuring between thoose two pins at the trafo showed only 0,5 ohm resistanse. It should be more than that if it was broken.?.😕
But why do they place the fuse such a stupid place as inside the transformer? Just to force us to buy new orginal parts?
I hope I get some time to look deeper in to this tomorrow.
Thanks
Tor Martin🙂
Thanks for advice.
My problem is that the player is completley dead. No light, nothing...
The only thing I know is that I have 230v after the switch. Haven`t had time to look any more in to it yet. All though I`m by education is an engineer I have to work at the postalservice (no engineering jobs around at the moment...) and now this close to christmas they would liked me to be at work around the clock!🙂
I fear that the power transformer somehow have broken. I don`t know why though....
I know that my original clock works, but the player should power up even without a clock.
I had hoped that it was the main fuse that were broken, but measuring between thoose two pins at the trafo showed only 0,5 ohm resistanse. It should be more than that if it was broken.?.😕
But why do they place the fuse such a stupid place as inside the transformer? Just to force us to buy new orginal parts?
I hope I get some time to look deeper in to this tomorrow.
Thanks
Tor Martin🙂
Hidden Fuse
Hello Tor,
Some transformers have hidden non-replacable fuses. Others have built in fuses that can be bypassed. I remember an Audio Alchemy supply. Can be a non resettable overtemperature fuse or a high current limiting one.
Quite simple if you have AC on the primaries you also should have AC on the secondaries. If not transformer dead/ Kaput.
It is all for for fire precaution I suppose.
Still remember that guy that had a defective fuse in his CD Player. He replaced the fuse by a bigger one, again and again and finally put in a 15A(!) car fuse. Then he blew the houses mainsfuse and I was called in because the player was causing problems....
Tor M said:
Hello Tor,
Some transformers have hidden non-replacable fuses. Others have built in fuses that can be bypassed. I remember an Audio Alchemy supply. Can be a non resettable overtemperature fuse or a high current limiting one.
Quite simple if you have AC on the primaries you also should have AC on the secondaries. If not transformer dead/ Kaput.
It is all for for fire precaution I suppose.
Still remember that guy that had a defective fuse in his CD Player. He replaced the fuse by a bigger one, again and again and finally put in a 15A(!) car fuse. Then he blew the houses mainsfuse and I was called in because the player was causing problems....
Hi Elso and everybody helping me out.
I finally got time to do some measuring.
I have voltage after the trafo. I measured about 9 v ac over the bridges. But here is the strange thing. All the - supplys seems to be fine, from the output of the bridge all the way through the player, but all the + supplys seems to give only 1-2V dc, starting at the bridge.😕
Does this means the diodes in the bridge used for + rectifying is gone? Or does the transformer put out some kind of werid ac.
I`m gonna measure the diodes now, and I`ll change them anyway to see if it helps.
I`ll let you know where the journey leads.
Thanks
Tor Martin🙂
I finally got time to do some measuring.
I have voltage after the trafo. I measured about 9 v ac over the bridges. But here is the strange thing. All the - supplys seems to be fine, from the output of the bridge all the way through the player, but all the + supplys seems to give only 1-2V dc, starting at the bridge.😕
Does this means the diodes in the bridge used for + rectifying is gone? Or does the transformer put out some kind of werid ac.
I`m gonna measure the diodes now, and I`ll change them anyway to see if it helps.
I`ll let you know where the journey leads.
Thanks
Tor Martin🙂
Ok changing the diodes didn`t help.
Also this time i noticed that the trafo gets very hot when powered on for a while. It`s probably broken just giving me negative pulses of the ac to rectify.
I guess I`ll have to get a local repair shop to order me a new one. Probably costs ten times a trafo thats not special made for Pioneer.
🙁 Tor Martin🙁
Also this time i noticed that the trafo gets very hot when powered on for a while. It`s probably broken just giving me negative pulses of the ac to rectify.
I guess I`ll have to get a local repair shop to order me a new one. Probably costs ten times a trafo thats not special made for Pioneer.
🙁 Tor Martin🙁
check ur trafo out of circuit (not connected to anything) if it has got the correct volatges it's probably ur bridge rectifiers, caps shorting out or regulators not working...should be a simple fix...and since u were messing with the clock...I would uess the regulator got shot somehow while u were fiddling around...
Hi!
Thanks, I`ll measure the trafo unconnected before I order a new one. But I think it`s probably the trafo where the main problem is.
There is two bridges in my player, one seperate for analog and one for the rest, and they are in paralell from the same secondarys on the trafo. They both show the same.
My guess is since it usen one bridge to make + and - dc probably only one of the secondarys are broken. I just measured over the bridge, not between the bridge "inputs" and the centretap (ground) so I`ll have to measure this But I`m off to work and tomorrow I`m going to London. So I don`t know when I get the time to do it.
Thanks
Tor Martin🙂
Thanks, I`ll measure the trafo unconnected before I order a new one. But I think it`s probably the trafo where the main problem is.
There is two bridges in my player, one seperate for analog and one for the rest, and they are in paralell from the same secondarys on the trafo. They both show the same.
My guess is since it usen one bridge to make + and - dc probably only one of the secondarys are broken. I just measured over the bridge, not between the bridge "inputs" and the centretap (ground) so I`ll have to measure this But I`m off to work and tomorrow I`m going to London. So I don`t know when I get the time to do it.
Thanks
Tor Martin🙂
it's probably not the trafo there...they dun spoil just suddenly...usually they fail with a lot of smnoke or at least a smell...and a secondary failing is even more rare...more often than not the primary goes open...
Tor, try to remember what you did prior to the disaster. Dropped someting into a bad place?
... modifying 100 times, hm. Maybe it's time to invest in something newer? A separate DAC maybe?
... modifying 100 times, hm. Maybe it's time to invest in something newer? A separate DAC maybe?
peranders said:
Per-Anders, come down from Mars.😀
The man has a broken CDP and you recommend a Dac?😕 😱
To connect where?
I guess PerAnders was saying that if he had modded his CD-player a hundred times (if that is possible) and still does not get the sound he wants..then there is something obviously very worng and he should try another path...the first sentence was to help him fix the non-working CDP...as in asking him what he did before the fault occured...hope I cleared it up...
He, he maybe a houndred times was a bit high.🙂
But I learn electronics step by step on my speartime and many a time the cd-player has been the place to try things out.
And I`m very pleased with this player! For it`s price it`s build like a rock! With stable platter, 24 bit 192kHz dac................... Very good. I have some TDA1543 laying around to build a dac, sometime.
As what happend just before I`m not shure. A friend of mine was over hanging around and I was a bit out of focus talking to him. So I might have shorted something or.........? I really don`t know what went wrong.
I have to go packing for my trip to London tomorrow!🙂
Thanks for helping me.
Tor Martin🙂
But I learn electronics step by step on my speartime and many a time the cd-player has been the place to try things out.
And I`m very pleased with this player! For it`s price it`s build like a rock! With stable platter, 24 bit 192kHz dac................... Very good. I have some TDA1543 laying around to build a dac, sometime.
As what happend just before I`m not shure. A friend of mine was over hanging around and I was a bit out of focus talking to him. So I might have shorted something or.........? I really don`t know what went wrong.
I have to go packing for my trip to London tomorrow!🙂
Thanks for helping me.
Tor Martin🙂
ar...too bad u can't bring the CD-player along...I guess you might have cooked the regulator when u were messing with the volatge to the DAC...or clock if u're using a seperate piece...
Hi!
I may have cooked some regulators. I`ll try changing them when I get back. There are no regulators at the negative supply, wich seems to be fine, so it might be so. But there are fusable resistors in front of every regulator. I thought they where to blow before the regulator, if not what`s the point of having them there.
Have a nice weekend🙂 (I know I will.)
Hope to find some nice HighEnd shops in London😉
Tor Martin
I may have cooked some regulators. I`ll try changing them when I get back. There are no regulators at the negative supply, wich seems to be fine, so it might be so. But there are fusable resistors in front of every regulator. I thought they where to blow before the regulator, if not what`s the point of having them there.
Have a nice weekend🙂 (I know I will.)
Hope to find some nice HighEnd shops in London😉
Tor Martin
Hi!🙂
I finally got time to mess around with my cd-player again.
I measured the transformer with no load, and it seems to be ok. I measured 10 V ac between the centertap and the two secondarys. With load I measured 7,5 on one and 0.25 on the other.
After this I changed two 7805 regulators for the digital supply.
This didn`t help.
So now there is only one regulator left, and this is some strange (for me) 5v sharp regulator called pq05rr12 with a reset pin.
Datasheet can be found here:
http://sharp-world.com/products/device/lineup/data/pdf/datasheet/pq05rr12_e.pdf
I must admit I didn`t fully understand how this workes.
I hope I can get the local pioneer shop to order this for me.
Hopefully this will fix my problems.
Maybe I`ll try to remove it to see if the other voltages gets allright.
Thanks for helping me.🙂
Tor Martin
I finally got time to mess around with my cd-player again.
I measured the transformer with no load, and it seems to be ok. I measured 10 V ac between the centertap and the two secondarys. With load I measured 7,5 on one and 0.25 on the other.
After this I changed two 7805 regulators for the digital supply.
This didn`t help.
So now there is only one regulator left, and this is some strange (for me) 5v sharp regulator called pq05rr12 with a reset pin.
Datasheet can be found here:
http://sharp-world.com/products/device/lineup/data/pdf/datasheet/pq05rr12_e.pdf
I must admit I didn`t fully understand how this workes.
I hope I can get the local pioneer shop to order this for me.
Hopefully this will fix my problems.
Maybe I`ll try to remove it to see if the other voltages gets allright.
Thanks for helping me.🙂
Tor Martin
Hi!
Ok I did something I should have done first of all, disconnected the jumper cable carrying the power between the powersupply/ analog pcb and digital pcb. The voltages suddenly were ok. This means that the trafo, the bridges and the pq05rr12 is ok.
There are 2 regulators at the digital pcb. Theese are the two 7805 regulators wich I changed for new ones this evening. So theese should be ok.
So now I don`t know what could be wrong!😕
If I get the time tomorrow I`ll measure if I can find any shorts on the digital pcb.
Any input of what could be wrong are appriciated!!
Thanks
Tor Martin
Ok I did something I should have done first of all, disconnected the jumper cable carrying the power between the powersupply/ analog pcb and digital pcb. The voltages suddenly were ok. This means that the trafo, the bridges and the pq05rr12 is ok.
There are 2 regulators at the digital pcb. Theese are the two 7805 regulators wich I changed for new ones this evening. So theese should be ok.
So now I don`t know what could be wrong!😕
If I get the time tomorrow I`ll measure if I can find any shorts on the digital pcb.
Any input of what could be wrong are appriciated!!
Thanks
Tor Martin
Yiipii!!😀
There is coming sound from my cd-player again!!!
I did some measurements again, and I found a short on the trace supplying one of the 7805 regulators. It turned out that a tiny smd cap was somehow covered with solder. I must have dropped some solder on it without noticing. I cleaned it and the player is now working again!🙂 🙂
It seems that the sound from one of the channels are slighltly louder than the other one, so I have to look the analog section over to see if there is a bad contact somewhere. But not tonight.
Right now I`m just very pleased with the fact that the player is working again!!
Thanks for help
Tor Martin🙂 🙂
There is coming sound from my cd-player again!!!
I did some measurements again, and I found a short on the trace supplying one of the 7805 regulators. It turned out that a tiny smd cap was somehow covered with solder. I must have dropped some solder on it without noticing. I cleaned it and the player is now working again!🙂 🙂
It seems that the sound from one of the channels are slighltly louder than the other one, so I have to look the analog section over to see if there is a bad contact somewhere. But not tonight.
Right now I`m just very pleased with the fact that the player is working again!!
Thanks for help
Tor Martin🙂 🙂
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