Yamaha ca-610 cracking and popping in right channels

[caseyaberhart]

hi people,

i'm a new user here, i have a problem with my yamaha ca-610, working fine for about a year after i bought it at garage sale, now it pops and crackles on right channels speakers A and B, regardless of volume setting, i love this amp and would like to fix it, i have a basic knowledge of electronics but in two-way radios. i was wondering what to check for, and any advice on how to fix it and what components to test, i'll post in other areas too, thanks for your time.

[jonman]

Have you cleand the switches and pots with Deoxit?

[mhardy6647]

It could indeed be any control or switch... the function selector will cause this when it gets dirty, based on my experience with my CA-610II. In fact, it's a bit dodgy now, but it's also too dang hard to extricate the amp from the 'entertainment center' it's in to clean it yet!

[wajobu]

Welcome casey! I second the other comments and encourage you to also clean the bass, treble and loudness pots in addition to the input and rec-out switches with the aforementioned DeoxIT.

For years I had a bass knob on my CA-810 that crackled, scratched and popped between setting 2 and 3. Then I found AK, cleaned the CA-810 and uh, er...got hooked buying other equipment! Now the CA-810 works great again!

Good luck and report back on your progress--again, welcome.

[caseyaberhart]

i will give it a good clean out, i noticed it pops and crackles in the right channels regardless of stereo or mono selection, i will clean out the switches, it does the same thing regardless of any switch position minus the power switch of course.

thanks for your help guys

[Fred Longworth]

If it pops and crackles with the volume at a minimum and only in the right channel, then the following is likely what's wrong:

>>>failure of the differential amplifier transistors at the front end of the power amp circuit in the right channel.

If, on the other hand, the popping and cracking occurs WHILE YOU ADVANCE OR RETARD the volume control, then you need to treat the control with Caig DeoxIT D5.

Best,

Fred Longworth
http://www.repairaudio.com
StereoTech Classic Audio Repair

[Cosmic Charlie]

I had a pioneer SA-9500 that suffered the same symptoms, only in the left ch. I removed and tested every transistor on the poweramp board, at least 20, they all tested ok. Reassembled w/ new caps still crackled and popped. Took it apart again and replaced the diff pair, works perfect now no problem. I had planned to swap left to right diff pairs, first time I had it apart, to see if problem followed to the right ch. but when they all checked ok I just replaced the caps, and was eager to try it out w/ new electrolytics and forgot to swap left to right diff pairs. Second or third time new diff pairs went in. I'd go w/ Fred on this one if volume has no effect. Good luck CC

[OvenMaster]

i will give it a good clean out, i noticed it pops and crackles in the right channels regardless of stereo or mono selection, i will clean out the switches, it does the same thing regardless of any switch position minus the power switch of course.

thanks for your help guys
A 610 may have a speaker protection relay. If you hear a "clack" 3 to 5 seconds after you turn your amp on, then you have one, and it's working. Dirty contacts within the relay may need cleaning. My CA-1010 had the same problem as yours recently. Until I can get my relay cover off to clean the contacts, a rap on the cover has temporarily put the issue on the back burner.
Tom

[mhardy6647]

The CA-610II definitely has a relay. Dunno about the original CA-610 (I've never seen one in the flesh).

[caseyaberhart]

Couldnt find any Caig DeoxIT D5, i tried some CRC switch cleaner and lubricant (not game to try WD-40, i read somewhere the hydrocarbons eat at the switch)

Tom (OvenMaster) and others RE: RELAY
Mine definiatly has protection relay, any ideas on how to get the relay cover off???

Fred longworth and others: TRANSISTORS

it's hard when i don't have a schematic, anyone like to share one with me? kcnem@dodo.com.au
where are these transistors in the CA-610 (not a CA-610II, though i believe they are very similar), are they in circuit testable? if so how??? whats the best and safest way to test an amplifier transistor? if it's had it...where can i get another?

should i be checking the power supply anyway even though it seems only one tranny is affected?

please go into detail on the testing process, like i said, i'm into RF electronics, hard for me to get my head around this amplifier stuff, i'm armed with various RF testing equipment but that aside it's just me, a multimeter, soldering iron (just bought larger tips for this repair, i usually solder surface mount stuff), and you guys in this forum.

thanks for your help guys

[caseyaberhart]

hi guys, i pulled the front cover off today, what an effort! very difficult to remove that volume knob, i also noticed that the heatsinked(big piece of black coated alloy) transistors in the 'main right channel' section of the board are getting very warm and the same transistors in the 'main left channel' section are stone cold, are these the symptoms of a power supply component failure? i think it is strange that the pair would both fail at the same time. for the time being the poor thing will lay on my bench with its pieces scattered around it, until i figure something out. thanks guys

[OvenMaster]

Tom (OvenMaster) and others RE: RELAY
Mine definiatly has protection relay, any ideas on how to get the relay cover off???
http://audiokarma.org/forums/showthread.php?t=19413&highlight=cover+shucker
Haven't yet tried it.
Tom