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 Search this Thread Display Modes
  #1   Report Post  
Posted to sci.electronics.repair
Bernhard Kuemel
 
Posts: n/a
Default Sony F570ES audio amplifier cracks

Hi ser!

My audio amplifier cracks, recently especially on 's' or 'sh'
sounds, as if the signal was overdriven. Also there are cracks when
the volume knob is adjusted and the left outputs channel mutes
occasionally, and it comes back when I turn the volume higher.

Here are some pics:

http://bksys.at/bernhard/img/x32/-gallery.html

I found 2 overheated resistors (1 watt rating, IMO). When I vacuumed
the dust some of the lacquer broke away, exposing the resistor
material helix, which looks quite ok. The small PCB in picture 4
(dscn7183) fits into the row of holes to the right of the overheated
resistors in picture 1 (dscn7174). It contains the volume adjust
resistor block.

What do you suggest?

Replace the 2 overheated resistors? Should I use 4 instead of each,
two parallel pairs in series, to avoid overheating? Unless I find a
4 W type, if there is such a thing. I don't see any potentiometers
nearby so I guess it wouldn't matter much if the value of the new
resistors differed within the rated tolerance.

Replace the volume resistor block? I'm afraid that might be hard to get.

Or might the fault be somewhere else?

Thank you, Bernhard
  #2   Report Post  
Posted to sci.electronics.repair
Bernhard Kuemel
 
Posts: n/a
Default Sony F570ES audio amplifier cracks

Replace the volume resistor block? I'm afraid that might be hard to get.

Do you think I might successfully test the resistor block by
connecting it to the line-in (or mic) input of my sound card in
series with a 1.5 V battery and see if there are any
discontinuities/cracks when I adjust the resistors?

Bernhard
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sony Audio amplifier takes long to "warm up" [email protected] Electronics Repair 5 July 13th 05 11:05 PM
Crackling Audio from Sony SLV-575 VCR Ken Electronics Repair 0 May 18th 05 02:54 PM
Crackling Audio from Sony SLV-575 VCR Ken Electronics Repair 0 May 18th 05 02:54 PM
Vintage R12R Ampeg - guitar amplifier - lack of audio output gain - need help [email protected] Electronics Repair 1 December 31st 03 03:39 PM
Sony KV27TS29 (Audio) Charlie East Electronics Repair 12 July 26th 03 04:08 AM


All times are GMT +1. The time now is 02:41 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"