Hi everyone! I seek help in what might be a simple fix for a new guy like myself. I replaced the switch 3P4T (but hope I soldered it in right) because I worked in some deoxit while the amp was one (dumb mistake) and somehow this created the relays to quit working.
1. I turned on the power and the lights come on - just no click anymore even after the new switch.
2. I do not get any DC voltage at the speaker terminals (which I think is a good thing).
3. The two 3.15 A fuses are okay.
4. I took 15 DCV power supply and touched the 3 relays and they all clicked (all are 24 DCV 2A rated) - so I think this is good.
5. Someone mentioned IC's, but I am not sure what or where I am looking for there for readings and if I am to turn on the power or measure with just an ohmmeter?
6. There is no sound out of the Headphone jack either - as I hooked up a CD player and speakers as well and nothing there - as I figured since the relays are stopping the power from getting to the terminals.
I have the schematic but the pages are broken up and it is tough to follow the lines, but I see some measurements but again where and what I need to see with these IC's someone mentioned is a bit tough.
Does anyone know if this is an output situation or other and what I can try to trace where the issue is to switch the bad part with the good? Any help would be greatly appreciated - thanks in advance...
1. I turned on the power and the lights come on - just no click anymore even after the new switch.
2. I do not get any DC voltage at the speaker terminals (which I think is a good thing).
3. The two 3.15 A fuses are okay.
4. I took 15 DCV power supply and touched the 3 relays and they all clicked (all are 24 DCV 2A rated) - so I think this is good.
5. Someone mentioned IC's, but I am not sure what or where I am looking for there for readings and if I am to turn on the power or measure with just an ohmmeter?
6. There is no sound out of the Headphone jack either - as I hooked up a CD player and speakers as well and nothing there - as I figured since the relays are stopping the power from getting to the terminals.
I have the schematic but the pages are broken up and it is tough to follow the lines, but I see some measurements but again where and what I need to see with these IC's someone mentioned is a bit tough.
Does anyone know if this is an output situation or other and what I can try to trace where the issue is to switch the bad part with the good? Any help would be greatly appreciated - thanks in advance...
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May I ask how I can do this DC offset test? I can try to find a video. I know I saw two bias adjustments but I think you mean the test where we put the neg of an meter on the chassis and touch the speaker terminals one at a time? But in any reading for DC offset is the rule - around 35? is good anything above 100? is bad? Sorry, I sort of understand but learning as I go.
I am wondering if there ever is a capacitor gone (just saying) on the terminal speaker board, there is no way to find it unless I take one leg out of circuit or buy an expensive ESR70 to help save time as there are so many vinyl style caps...I would post photos but I have a tough time on here, but I think it is Firefox's tracking protection?!
I got near zero volts on both R177 and R178; I measured both sides of each using the red lead of my meter on the center pin and got 0.002-0.004V on each.
For the hell of it I put my meter on AC and just touched the chasis and there is about 6VAC!
But anyway, this is with the speaker switch turned to A position, then B and C. Here though I am not sure if I got the leads on the right switching choice. All I cared for or hoping was that I can use A/B.
This amp was set perfect and ran without a hitch...sort of wished I did not try to sell it after it got damaged in the postal transit process. The plastics are all fixed, just the relays are not engaging, but only when I touched them with a 15VDC source.
Was I supposed to see Zero volts? If not, I wonder which component I stressed out by turning the speaker switch on and off to work in the deoxit?
I appreciate your help thank you kindly!
Do you know what you are doing and why anyone would apply 15VDC to the relay, assuming you are speaking of the coil which actuates it, not the contacts which break/make the speaker connections?
The plan is to have reliable speaker protection by a circuit which senses DC at the output of the power amplifiers, as opposed to AC (audio) or nothing. The speaker side of the relay contacts will show nothing until the contacts close so you must measure on the amplifier side of each pair of contacts, L & R channels, as Jon advised. If you have done this correctly and only read 1 & 2 mV as you say, that's commendably low for any amplifier (suspect actually). With the speakers still disconnected, play some music at low level in that condition and confirm that you now have lots of AC (audio) there, causing the meter to go crazy on an AC setting or the bargraph which will be more readable, if you have one on your meter.
From there, we can deduce where the problem arises but let's see what you have (or not) at the power amplifiers themselves, first.
The plan is to have reliable speaker protection by a circuit which senses DC at the output of the power amplifiers, as opposed to AC (audio) or nothing. The speaker side of the relay contacts will show nothing until the contacts close so you must measure on the amplifier side of each pair of contacts, L & R channels, as Jon advised. If you have done this correctly and only read 1 & 2 mV as you say, that's commendably low for any amplifier (suspect actually). With the speakers still disconnected, play some music at low level in that condition and confirm that you now have lots of AC (audio) there, causing the meter to go crazy on an AC setting or the bargraph which will be more readable, if you have one on your meter.
From there, we can deduce where the problem arises but let's see what you have (or not) at the power amplifiers themselves, first.
I was seeing if the relays were still functional which they must be if they clicked...
What pins do I measure from the relays? There are 6 - coil has two and the other end of Each relay (3 of them) have 4 pins. I only touched the two front ones with the 15VDC to hear them click.
I need to find which is the hot side of the relays...
Yes, I have already taken music at low levels to each terminal and heard no hiss or sound, neither out of the headphones!
But, mind you I will do this again and try to click each part of my switch as I forget if I clicked it to see if it was A, B and C (A/B).
If the relays are 'stuck' will they work if this power (is it DC or AC) going to them to close/open the contacts...?
The schematic I have is touch to see at 300% as it looks like one relay might have two coils?
To recap:
1. Power switch on lights up and also the power boards left and right
2. R177/178 are reading near Zero on the 3 pins - red probe in the center
3. Switch is soldered on but not sure if fully correct - meaning starting in the off position then first click would be Speakers A, then next click B etc... - but would think one of them would engage the speakers.
4. Source hooked up with speakers on A side heard no sound at all.
5. Fuses are good
6. Used a Dim Bulb Tester and there are no shorts as bulb goes Dim quickly upon turning on the amp.
7. No clicks to the relays - all resistors on the Power Supply are fine and so are the resistors to the Speaker board. (Power Board - I mean the board with the two 3.15A fuses just under the transformer).
Cause to the issue:
May have stressed something in the circuit by turning on and off the speaker selector switch while working in deoxit (rookie here) while the darn amp was on. The relays kept clicking on and off then suddenly quit, after that I thought it was the switch (switch was badly oxidized anyway)...
Thanks guys I appreciate the guidance...if you want this amp for parts let me know...I know it has to be simple but wow, learning this stuff is a bit of a curve!
And if you are OK with circuit schematics, there is a service manual for free download, after registering here: Pioneer A-676 - Manual - Stereo Integrated Amplifier - HiFi Engine
Wow, what an offer. You can pop over anytime and help me out Chris 
, I’ll throw some prawns on the bbq, crank the tunes and ask 1 million questions.
From what I’ve read above I totally agree, sounds like 24moons needs help.
I have been slowly educating myself analog audio electronics, mostly with information contained within this forum. It takes time and patience, there are know shortcuts. I’ve got a rather nice amp myself in need of repair. Do I have the necessary experience and skills to repair it? No.
Audio service Tech’s are skilled in all aspects of amplifier repair, and there is a lot going on inside an amplifier. Learn to crawl before you walk. Good luck and keep learning.
, I’ll throw some prawns on the bbq, crank the tunes and ask 1 million questions.From what I’ve read above I totally agree, sounds like 24moons needs help.
I have been slowly educating myself analog audio electronics, mostly with information contained within this forum. It takes time and patience, there are know shortcuts. I’ve got a rather nice amp myself in need of repair. Do I have the necessary experience and skills to repair it? No.
Audio service Tech’s are skilled in all aspects of amplifier repair, and there is a lot going on inside an amplifier. Learn to crawl before you walk. Good luck and keep learning.
Hi Bix,
I guess I would need air fare and a place to crash. Also the use of some decent equipment for the duration. Once the amp is done it's time to party! Of course you would hang out with me as we fixed the amp and I could even direct you on measurements we need.
The big problem with that deal is the cost of getting me there and back! The test gear can be rented for a week or something like that. Not unless you have purchased some decent equipment.
However, Ian is a good tech and he is much closer to you than I am.
I think the biggest step in learning is to use your common sense. If you don't understand something, ask.
Best, Chris
I guess I would need air fare and a place to crash. Also the use of some decent equipment for the duration. Once the amp is done it's time to party! Of course you would hang out with me as we fixed the amp and I could even direct you on measurements we need.
The big problem with that deal is the cost of getting me there and back! The test gear can be rented for a week or something like that. Not unless you have purchased some decent equipment.
However, Ian is a good tech and he is much closer to you than I am.
I think the biggest step in learning is to use your common sense. If you don't understand something, ask.
Best, Chris
I am too far from you. I won't be sending this one in the mail again! I did not get insurance for this unit...Canada Post says it must handle a 3 foot drop! Thus, why I am trying to fix as it 'was' in mint condition...I might pull the relays and cut them open to see if they will go back to their initial position.
I tried to find related issues but most YT vids are not quite on spot...most are on car relays.
I was going to pack it up and leave it for another time...but I have photos of the step by step process to put it back together and have to put them somewhere with the amp so I do not forget. The face plate is plastic on the inside so it is delicate.
I may have the switch soldered in wrong - maybe I started with A being on pins 5-8, B pins 9-12, and A+B 1-4. When I switch it to these nothing still clicks out of the relay, but as the other guy mentioned the relay is still open?? I see the hot side which I think from the schematic that it is to the left...right will 'become' hot when closed...so I think I understand the short message meaning to check the 'hot' side, which I now just figured out as I write this message so I will go check it.
I am willing to pay via paypal for help online, I am not that novice to check stuff, but new enough to not know where to look.
Alberta....
I tried to find related issues but most YT vids are not quite on spot...most are on car relays.
I was going to pack it up and leave it for another time...but I have photos of the step by step process to put it back together and have to put them somewhere with the amp so I do not forget. The face plate is plastic on the inside so it is delicate.
I may have the switch soldered in wrong - maybe I started with A being on pins 5-8, B pins 9-12, and A+B 1-4. When I switch it to these nothing still clicks out of the relay, but as the other guy mentioned the relay is still open?? I see the hot side which I think from the schematic that it is to the left...right will 'become' hot when closed...so I think I understand the short message meaning to check the 'hot' side, which I now just figured out as I write this message so I will go check it.
I am willing to pay via paypal for help online, I am not that novice to check stuff, but new enough to not know where to look.
Alberta....
Hi guys, Yes I have the schematic! I've been trying to follow it but the pages of course do not print as one, so following it was/is a bit tricky.
Do you guys think that if I wired my switch in the wrong order, would that still cause the relays to not release (that is if they are open - not allowing the current to get to the speaker assembly).
The switch circuit board - I was a first timer on soldering and of course 3 traces came off, but I have a shunt one one line/circuit trace and the others scraped off the material and soldered them...all checked out for continuity.
Do not get me wrong, I have a background in electrical apprentice and DC/AC theory in electronics...long story on why I did not finish...sigh! LOL
I have been at this each day for since March and I do not wish to give up but I need to paint part of my house and I hate to put this back together (as I would forget later - probably already now!!) and try later or just sell it for parts. My pride says I can, my short comings say otherwise!
I know this is a free site but I always like to offer something in return for the help. This is a hobby I started, but finding out the equipment is going to be pricey, what I have is:
Auto multimeter
100 Mhz Hitachi Analog Scope all set up and calibrated (by professional)
Hand tools of course (novice at this instrument)
Component Tester that tells you unknown parts (Chinese thingy everyone swears by - you can buy from Bangood but I got this from Bay)...
DLB tester for shorts
Bread board stuff and lots of caps/resistors/transistors but would buy from Digitek or Mouser as these came from Bay...
I am confident I can follow you guys for sure, just never played around with the amplifier stuff before as I was going for the hobby side, but as all of probably get a 'kick' whether how much it ends up being - fixing something!
Cheers,
Richard
Alberta, Canada
Thank you Bix, yes, it has been since 1990 since I took electronics, but only got up to the AC/DC and part of transistor theory - family issues so I had to step down...I was top of my class and it was sad to go. Here I am now half a century old and excited to learn, but not so on the cost of the equipment.Wow, what an offer. You can pop over anytime and help me out Chris
From what I’ve read above I totally agree, sounds like 24moons needs help.
I have been slowly educating myself analog audio electronics, mostly with information contained within this forum. It takes time and patience, there are know shortcuts. I’ve got a rather nice amp myself in need of repair. Do I have the necessary experience and skills to repair it? No.
Audio service Tech’s are skilled in all aspects of amplifier repair, and there is a lot going on inside an amplifier. Learn to crawl before you walk. Good luck and keep learning.
But one thing at a time, like buying tools!
The amp I paid $280, I sold it for $350, got dinged up in the mail where the MC/MM dial was pushed into the amp. Got it home it all worked fine, except I noticed the speaker switch was for crap...this was not the case before I sent it either...not sure what happened there. So, I used epoxy and fixed the long hairline crack along the other smaller dials, now strong as ever, I got onto some site and was told to try deoxit for the switch...so I did but stupid me, I did not turn off the amp while working it in...thus, the relays worked lovely until a few clicks quickly back and forth! But the switch was in dire despair...I could not find one so I order guitar ones (that is what they look to be) that have 12 pins and 3 ground pins (3P4T).
Starting at 1 o'clock is pin One moving counter is 2 and so on...so A+B is wired in as 1-4.....A is 5-8 and B is 9-12...no luck, but again there is no power getting to the relays...
Cheers and nice to meet you on here!
Thank you Chris - this is a tough one, four months in but I need to take a break and I think I will leave this one the 'bench' (my Bar) and just go paint and try for more videos. I hope you do not mind me offering a little something to anyone that can help...I believe in giving back as I hate to make this a free for all...
I know for parts this may be a good find, but I am seeing only the 230V in the UK and Poland exist. Man I tell ya' this is a nice sounding amplifier and I am not going to give up, I will just keep at the thing. I just hope if I cut open the relays with a dremel to try to see if they are stuck and 'fix' that that may be either a go or 'no go' situation!
Those switches are a pain to solder, so I used jumpers solid wire running from the switch to the switch PCB...I might have to rebuild the board, thank goodness it is straight forward...I might try bread boarding the circuit first and see if I can get the 3P4T switch lead correctly. I am thinking Speaker A is starting at pin 5 --> 8 B 9-12 A+B 1-4
Thank you for the offer...I am not working right now otherwise I would chance the mail system but I am going to use FedEx of something...CP I just dislike only getting back the postal cost and not the coverage which they should have done...3ft is a big fall to still be 'our' fault when it is dropped by 'them'! LOL
Cheers
Richard -
Hi Richard,
If you need to ship something and don't want to use the post office, I find that Fedex is about the best.
You really need to learn how to solder.
1) Buy a real soldering station with a digital display that lets you set the temperature.
2) Get some leaded solder if you don't already have some
3) Get some good hand tools. Xcelite or equivalent. Yes, $30 for a pair of pliers and so forth
4) Buy a good, full size desoldering tool. It should cost your about $30, Edsyn only
5) Get some desoldering wick in a medium - wide width, and something a bit more narrow
6) Practice soldering and desoldering on old boards from whatever.
7) Buy some cheap kits off Ebay or wherever. A clock kit is a good starter. You need soldering practice.
These kits can be assembled in 2 hours or less and make a good break from something else. With luck, you can build things that are useful to you and your wife. They are fun, but more importantly you will learn how to solder. It's a skill and needs practice as you have seen. If you have one of those mini solder suckers, use it for target practice at a shooting range. Same thing goes for those desoldering "bulbs". They are both useless.
When you buy a soldering station, buy an assortment of tips immediately. The conical tips are useless. You want the "screwdriver" tips, sometimes called "chisel" tips. You want the biggest one for sure (3mm) and then some medium and small ones all the same style. If you ever try to solder something using the other tios, you'll understand why as soon as you switch to a screwdriver of chisel style tip. Your soldering iron is a basic tool, do not skimp on this.
Good luck with your new hobby. It can become extremely useful to have skill in this area.
-Chris
If you need to ship something and don't want to use the post office, I find that Fedex is about the best.
You really need to learn how to solder.
1) Buy a real soldering station with a digital display that lets you set the temperature.
2) Get some leaded solder if you don't already have some
3) Get some good hand tools. Xcelite or equivalent. Yes, $30 for a pair of pliers and so forth
4) Buy a good, full size desoldering tool. It should cost your about $30, Edsyn only
5) Get some desoldering wick in a medium - wide width, and something a bit more narrow
6) Practice soldering and desoldering on old boards from whatever.
7) Buy some cheap kits off Ebay or wherever. A clock kit is a good starter. You need soldering practice.
These kits can be assembled in 2 hours or less and make a good break from something else. With luck, you can build things that are useful to you and your wife. They are fun, but more importantly you will learn how to solder. It's a skill and needs practice as you have seen. If you have one of those mini solder suckers, use it for target practice at a shooting range. Same thing goes for those desoldering "bulbs". They are both useless.
When you buy a soldering station, buy an assortment of tips immediately. The conical tips are useless. You want the "screwdriver" tips, sometimes called "chisel" tips. You want the biggest one for sure (3mm) and then some medium and small ones all the same style. If you ever try to solder something using the other tios, you'll understand why as soon as you switch to a screwdriver of chisel style tip. Your soldering iron is a basic tool, do not skimp on this.
Good luck with your new hobby. It can become extremely useful to have skill in this area.
-Chris
Hi Chris,
Thank you for that info. I actually have most of this just not the station I have a Chinese Variable that goes to 450 or 60W I set it back a bit.
I was wondering about the solder with lead, I have none! I have dental pick, I have helping hands (had to tape the 'teeth' it likes to 'chew' the darn PCB, so I am careful there.
Is there a way to send photos I can do a photo shoot! Funny, I had an ad up for free electronics and people were giving me working amps (Pioneer cheap movie one) and a computer that did not work but I am great at that (certified years ago/diploma in repair).
I have practiced the soldering art, but never ran into the 'eyelets' coming off. I used some crazy glue (LePage's) to keep one that was coming out in tact...seems to work at there was a complete circuit! LOL
I have tons of tools.
Just not a signal generator, Rigol Digital Scope, Frequency thingy, variac, and ran out of Southern Comfort! LOL
I got the wick, irons, wrong solder, computer repair tools...
I better send this message I wrote you a large one and it times me out! Sorry...missed out on some stuff I own no biggy!
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