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
|
|||
|
|||
TFM5380 vs TSOP1738
Just sharing an experience.
Got this Harman/Kardan AVR20 MkII receiver amp for repair with a no remote operation complaint. Tested the remote control on my remote tester( the plug in the wall type that shrieks when IR hits it) and it seemed fine. Opened the amp looked for a signal at the 3 legged IR receiver's output pin (TFM5380) and found none. Inquired and hunted in the local market and i couldnt find it. Checked the datasheet and it's specs seemed almost identical to those of TSOP1738, with one exception; TSOP1738 features mentioned "Suitable burst length .10 cycles/burst" while TFM5380 datasheet stated "Continuous transmission possible (tpi/T0.4)" I decided to try the TSOP1738. The remote would work but intermittently. I desoldered all microswitches in the microcontrollers (CXP50116) key matrix thinking some leakage in one or more of the switches might be mis-interpretted as a key being pressed which might have priority over IR input. No change. Forced the External Interrupt pin of the microcontroller low (active high), still worked errantly.My heart sank, damn, could it be the microcontroller itself? Where'd i get one with the same suffix CXP50116-652. Went back to the market and hunted for an alternative to TSOP1738. This shopkeeper had one in the same package without any number printed or etched into it. Bought it, soldered it in place and the unit works FINE. Tested it over distance too. He, the shopkeeper, said he'd got feedback from several technicians that it worked like a breeze. So, was the remote command string longer than 10 cycles/burst????? Jango |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|