Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to sci.electronics.repair
|
|||
|
|||
Pioneer DEH-P4600MP Car Receiver Left goes out - "DEH-P460MP_4600_4650 22.pdf" 109.9 KBytes
wrote in message ... Hello, I have a DEH-P4600MP that I installed a IP Bus Ipod adapter (ip bus to 3.5 mini plug) on and it worked ok for a while. I think my iphone may have put to hot of a signal in the input of the E-Vol chip PML003. The unit will play all channels when it is first turned on, but after about 2-3 minutes the left side (front and rear) start to distort and then fades off. I have it apart and the E-Vol smt starts to get warm and then hot after about 2-3 mins. After it gets real hot the left side goes out. I have cooled it down with compressed air (can upside down) and the left side will start working again. Right side works all the time. There are a few caps around this chip and I was thinking it was a bad cap, but a bap cap(s) shouldn't make the chip get hot. I don't guess. I also used a ESR meter on the caps and they show the same values as the another unit I have. (4.7uf and 1uf at 50v) This is a SMT chip and I have another one on a spare unit. Any way... Does anyone have any ideas on this? I think it is a bad chip, but would like another opinion. Plus, I don't have a lot of experience removing and installing SMT chips. I attached a PDF of this circuit. TIA! You learn something new every day - I never knew that news servers would accept posts with attachments ! Does this mean that when people post links to web-hosted pictures of their problems, they could in fact just post the jpg to the NG as an attachment ? Or does it only work with some types of file, such as the pdf that this poster has placed here ? Oh yes. And FWIW, I would be going with it being the chip as well, if it gets hot and goes off, but can be restored by freezing. Another possibility however, is that the chip runs quite hot as normal, and it has a badly soldered pin (not at all unusual these days, especially on sm chips mounted with lead-free solder). I have seen joints like this go bad and come right with temperature cycling. Might be worth running a very fine-tipped iron over them. Add some liquid flux to the pins before starting, and this will help to stop the solder flowing between pins. It's only a 28 pinner, so if you do need to get it out, it shouldn't present too much of a problem. Ideally, you use a hot air pencil, but if you do not have access to one of these, there are plenty of other destructive and non-destructive techniques for removal. The replacement can be fitted with a very fine tipped iron, angel-hair solder, and of course, liquid flux. Some really strong light and magnification for your eyes, is also helpful. I have a stereo microscope for this work, but I also have a headband stereo magnifier that's just about adequate for pin pitches down to about a quarter mm. Arfa |
#2
Posted to sci.electronics.repair
|
|||
|
|||
Pioneer DEH-P4600MP Car Receiver Left goes out -"DEH-P460MP_4600_4650 22.pdf" 109.9 KBytes
Arfa Daily wrote: wrote in message ... Hello, I have a DEH-P4600MP that I installed a IP Bus Ipod adapter (ip bus to 3.5 mini plug) on and it worked ok for a while. I think my iphone may have put to hot of a signal in the input of the E-Vol chip PML003. The unit will play all channels when it is first turned on, but after about 2-3 minutes the left side (front and rear) start to distort and then fades off. I have it apart and the E-Vol smt starts to get warm and then hot after about 2-3 mins. After it gets real hot the left side goes out. I have cooled it down with compressed air (can upside down) and the left side will start working again. Right side works all the time. There are a few caps around this chip and I was thinking it was a bad cap, but a bap cap(s) shouldn't make the chip get hot. I don't guess. I also used a ESR meter on the caps and they show the same values as the another unit I have. (4.7uf and 1uf at 50v) This is a SMT chip and I have another one on a spare unit. Any way... Does anyone have any ideas on this? I think it is a bad chip, but would like another opinion. Plus, I don't have a lot of experience removing and installing SMT chips. I attached a PDF of this circuit. TIA! You learn something new every day - I never knew that news servers would accept posts with attachments ! Does this mean that when people post links to web-hosted pictures of their problems, they could in fact just post the jpg to the NG as an attachment ? Or does it only work with some types of file, such as the pdf that this poster has placed here ? A lot of news servers drop anything with a binary attachment, or strip it from the test portion. news:alt.binaries.schematics.electronic is a newsgroup for the exchange of schematics. -- You can't have a sense of humor, if you have no sense! |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Pioneer DEH-P4600MP | Electronics Repair | |||
AC voltage measurement question - "4.5VAC-powersupply.jpg" (0/1) 102.3 kBytes yEnc | Electronic Schematics | |||
AC voltage measurement question - "4.5VAC-powersupply.jpg" (1/1) 102.3 kBytes yEnc | Electronic Schematics | |||
Advice Buying "Blade-Left" Circular Saw Sidewinder or Worms | Woodworking |