Sony TAF40 LED Repair

[dogtownman]

Hello i have an old sony f40 amplifier all works fine apart from one of the Led meters only lights one bar out of six..the other channel is fine and bounces with the music...I think it is the IC 551 Chip that operates the light strip that has the fault.but can not find one anywhere on google search..would anyone know a replacement chip..IC 551 9 pin..Thanks for any help ..

 

[Sunnysky]

pin 9 is V+=13V
pin8 is rectified sig. input., compare all pins.
http://www.hifiengine.com/hfe_downloads/index.php?sony/sony_ta-f40_service.pdf

 

[73's de Edd]

Sir dogtownman . . . . . . . . .
(where do this dog town be ?)


Initially place a jumper between both IC's pin 8 'S to see if the ? units dormant LED's come alive at higher levels.
If not then pull and out and interchange the twin / companion IC's . . . to see if the conditions then move between them.
Then n n n n n you will see if you are in the market for a new BA656.

http://www.ebay.co.uk/sch/i.html?_f...3.TR0.TRC0.H0.XBA656.TRS0&_nkw=BA656&_sacat=0


73's de Edd

 

[dogtownman]

Thanks de ed ..i just tested the led's with your jumper method and they all light up when i moved along each one ..so a new driver it is then..
Dogtown ..just made that up as a user name.. I'm Phil...from cheshire UK.. Great site this..!!

 

[Sunnysky]

He meant jumper the input to the chip on pin 8 not the driver outputs

 

[dogtownman]

Thankyou so much....i have just soldered the new IC in and the led's are now both dancing away..very happy..;0
I'm new to electronics but love to learn.no doubt will be back on for some more advice..