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
|
|||
|
|||
problem with a TEAC CD-Z500
When I insert a CD in the tray : 1- the drawer closes perfectely ... no problem, 2- there are no interlock switch on this model 3- the pickup assembly reset to the starting point to the inner center track of disc with no problem, servo circuitry sounds ok... 4- the laser pickup assembly move freely and smoothly on the track, 5- THE PICKUP LASER DO NOT FOCUS AT ALL WITH OR WITHOUT A DISC (CD), 6- NO RED SPOT WHEN I VIEW THE LENS FROM AN OBLIQUE ANGLE DURING FOCUS SEARCH either the supply to the laser diode is missing or the laser pickup itself is faulty. motor wont start unless focus lock is achieved. if I had to make a blind guess without a service manual, I'd say the laser is shot. alex. 7- NO SPINNING MOTOR ACTION |
#3
|
|||
|
|||
problem with a TEAC CD-Z500
3a- the laser beam goes on for 4 sec and shut down Manually (with power off), guide the sled gear so that the laser pickup is at the outter edge of the disc. Start the unit and observe. If the laser diode comes on after the pickup has reset to the inner side, whilst the laser lens is ramping up and down, this is normal. Check (with the power off), to make sure the spindle motor isnt jammed/sticky. other than that, laser pickups can still be faulty even if a glow can be seen from it. Perhaps its intensity/gain is too low and it is unable to see the disc. generally, servo faults are not very common. most circuitry is pretty robust. Try bending the flexi cable from the pickup just before it begins to check for the disc. If the unit springs back to life, then the problem is pretty obvious. Continutity tests do not always eliminate the possibility of a flexi cable being faulty, because it could going open circuit only on a certain angle. Sony Pickups are not really of great quality, the newer Sharp pickups have been the worstly constructed ones I have ever seen, and they drop like flies. Have a look to see if the lens has sagged all the way to the bottom. This is another sign.U can check this by lightly (very lightly) pressing on the *side* of the laser lens (with a blunt pointed tool) and see if it does down any further. This can cause servo IC's to get hot because it has to constantly work to keep the lens at the correct height. Worn motors which are drawing more current than usual, will cause servo circuitry to run hot. I still think your culprit is a flexi cable or laser. Theres not likely to be a "quick fix" that anyone can suggest, and you say that you have cleaned the laser lens, and checked the basic stuff, you're going to have to start buying parts or at least a service manual. Alex. 4- the laser pickup assembly move freely and smoothly on the track, 5- THE PICKUP LASER DO NOT FOCUS AT ALL WITH OR WITHOUT A DISC (CD), 6- NO RED SPOT WHEN I VIEW THE LENS FROM AN OBLIQUE ANGLE DURING FOCUS SEARCH 7- NO SPINNING MOTOR ACTION I checked the following: 1- I clean the lens, 2- no broken or damaged gear theeth anywhere, 3- the drawer close completely and freely, 4- the (path) track is clean and freely, 5- all flat cables and connectors OK, 6- sloder joints OK 6- my CD (disc) is clean with no scratch on it 7- power transformer seem very hot but everything light (display, motor tray OK), 8- the DACs (2x) on the audio PCB (at left of the pickup) runs hot 9- voltage according to regulators (7805, 7905, 7815 = OK) There are the following parts in the servo control: STA341M IC motor P/N array driver NJM4565L ??? LA6500 regulators (no info ??? on voltage output in the power supply section). I checked all transistors and resistors including low resistors values = everything looks OK! There is an optical sensor under the laser pickup assembly, and the laser pickup part number is a Sony number KSS150. Funny thing, all parts on the PCB board are SONY! (pcb located right of the picup assembly) No service manual, schematic, or data info ..service manual is 85$$ too expensive for me. TEAC customer service is really bad! Anybody knows this model and trouble associated ... someone can help me ... Thanks a lot! Mike |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Quick Change TP problem | Metalworking | |||
jointer problem | Woodworking | |||
Boiler Problem Gradually Getting Worse | UK diy | |||
Problem with JET Supersaw problem | Woodworking | |||
Sears air compressor starting problem | Woodworking |