mechanicalman said:
Really,
There not that way it is on mine, and in the manual they show
that they use them. In fact I have never had a piece of Marantz
gear come though here that did not use them.
Yes its better but its no good for your application.
Good - because you need to get new insulators on the ones you
replaced.
Hi mechanicalman,
Now, this is critically important. Why on earth would you consider beginning to work on something without the manual???? This amplifier is well worth getting the service manual for. So is the 1300 DC. Step number one is to get the manual. For both.
When I was running a shop, my rule was pretty simple. As long as the manual was not outrageously priced and it would save at least 1/2 hour, I bought the manual. I had 8 filing cabinets full by the time I sold my place and I dearly miss them.
Okay. To prevent scratching the resist layer off, I use a little lacquer thinner on a toothbrush. Keep plastics protected. You can also use a cotton swab. On some jobs, I follow this with a wash of "Electrowash 2000". You have to keep these things away from electrolytic capacitors and adjustable controls of any kind. Cleaning the flux off is a very important step as it reveals any solder bridges or splashes. Ends of wire can also be stuck in flux where you really don't want them.
1. Take many digital pictures of the original PCB with all the parts installed. Do the same for the good channel.
2. Remove all the parts of the PCB. List actual values as they can differ from the schematic sometimes. The parts list in the manual is a good crosscheck. Confirm with the good channel PCB.
3. using the old PCB as a guide, cut a piece of new epoxy PCB material, 2 oz if you can get it or 1 oz minimum. Line the two board up and fasten them together. Tape works well if you keep it tight and do two on each side. You do not want the boards sifting around. If you use two blanks and the original, you can set up two new PCBs.
4. Using the old PCB as a guide (all foils facing up), drill out all the holes with the same size drill bit as the original hole. You want them exactly were the old ones were.
5. Each hole will have a raised edge around it. Use some steel wool or a razor if you're really good. You need to debur all those holes. Be careful not to damage the copper near the holes. You need that undamaged. Clean the foil sides of the new drilled blanks carefully. You cannot leave any finger oils or anything on the surface.
6. Using a good etch resist pen, connect the dots. Then make the traces and lands look as close as you can to what the original should have looked like. I like the bluing ink type resist pens. The black sharpie types do not work nearly as well. You can use nail polish carefully, but you would need to be some artist to do a good job.
7. Allow the resist layer to properly set. I like to put plastic over it to keep the dust out, but the plastic is held a few inches off.
8. Etch the PCB. You will want to use gloves handling acid. Do not touch the surface. I normally use ferric chloride and warm it up. Float the board copper side down. You can see the traces show up. Move the board to dislodge air bubbles every couple minutes. Let it etch past where you think it's done to get rid of the small copper specs that will probably remain for a bit. Here is where your choice on resist pen will help or hurt you.
9. Once the etching is complete, rinse the board with plenty of water to stop the etching process. Again, you will want to use gloves handling acid.
10. Inspect the board for complete etching. You can return it to the acid as long as the resist is undamaged.
11. Remove the resist. I use lacquer thinners again on a paper towel. Once the resist has been removed, inspect the copper traces for breaks where the etchant ate the copper away where you wanted it. If the resist failed, you will see pink copper. At this point you can tin plate the traces, or solder plate it using liquid solder flux and solder wick with some solder. You could also paint the areas where solder doesn't go with a sealing type pen or nail polish.
12. Stuff the new PCB(s) and remount them onto the heat sink.
13. Follow your power up procedure.
I have recreated PCBs for hacked equipment over the years. It's expensive, but there are times that this would be the only reliable repair. Trace damage or broken PCBs are the two reasons a new board is made.
Good luck with this one. I feel you are on the right track by making a new circuit board from what you describe.
-Chris
Yes, the original ones on the PCB with small heat sinks. Check to make sure that an original wasn't completely encased and a replacement didn't have exposed metal tabs or metallic areas.
There is a great example of how some people can get others into heaps of trouble. Direct the helpful know-it-all to this thread. I already know he doesn't believe you. I wonder how many problems this guy has created.
It's very light. Go to the On Semi web site. Under something along the lines of "installation" or "mounting semiconductors" will be some mounting torque figures. Other manufacturers have torque charts as well. Most technicians over tighten semiconductors. What can easily happen is that the semiconductor package and / or heat sink is bent. This causes a loss of contact area (semi runs too hot) or the die inside the package can crack or fracture from the bonding area. Either way, this might not show up for a while.
That could be a critical error that doesn't show up for years. Better check both channels.
It also explains how the circuits work and gives you other information.
Now, this is critically important. Why on earth would you consider beginning to work on something without the manual???? This amplifier is well worth getting the service manual for. So is the 1300 DC. Step number one is to get the manual. For both.
When I was running a shop, my rule was pretty simple. As long as the manual was not outrageously priced and it would save at least 1/2 hour, I bought the manual. I had 8 filing cabinets full by the time I sold my place and I dearly miss them.
Okay. To prevent scratching the resist layer off, I use a little lacquer thinner on a toothbrush. Keep plastics protected. You can also use a cotton swab. On some jobs, I follow this with a wash of "Electrowash 2000". You have to keep these things away from electrolytic capacitors and adjustable controls of any kind. Cleaning the flux off is a very important step as it reveals any solder bridges or splashes. Ends of wire can also be stuck in flux where you really don't want them.
If the original PCB(s) are cracked or the traces are badly damaged, making a new PCB is the way to go. It's easier than you think.
1. Take many digital pictures of the original PCB with all the parts installed. Do the same for the good channel.
2. Remove all the parts of the PCB. List actual values as they can differ from the schematic sometimes. The parts list in the manual is a good crosscheck. Confirm with the good channel PCB.
3. using the old PCB as a guide, cut a piece of new epoxy PCB material, 2 oz if you can get it or 1 oz minimum. Line the two board up and fasten them together. Tape works well if you keep it tight and do two on each side. You do not want the boards sifting around. If you use two blanks and the original, you can set up two new PCBs.
4. Using the old PCB as a guide (all foils facing up), drill out all the holes with the same size drill bit as the original hole. You want them exactly were the old ones were.
5. Each hole will have a raised edge around it. Use some steel wool or a razor if you're really good. You need to debur all those holes. Be careful not to damage the copper near the holes. You need that undamaged. Clean the foil sides of the new drilled blanks carefully. You cannot leave any finger oils or anything on the surface.
6. Using a good etch resist pen, connect the dots. Then make the traces and lands look as close as you can to what the original should have looked like. I like the bluing ink type resist pens. The black sharpie types do not work nearly as well. You can use nail polish carefully, but you would need to be some artist to do a good job.
7. Allow the resist layer to properly set. I like to put plastic over it to keep the dust out, but the plastic is held a few inches off.
8. Etch the PCB. You will want to use gloves handling acid. Do not touch the surface. I normally use ferric chloride and warm it up. Float the board copper side down. You can see the traces show up. Move the board to dislodge air bubbles every couple minutes. Let it etch past where you think it's done to get rid of the small copper specs that will probably remain for a bit. Here is where your choice on resist pen will help or hurt you.
9. Once the etching is complete, rinse the board with plenty of water to stop the etching process. Again, you will want to use gloves handling acid.
10. Inspect the board for complete etching. You can return it to the acid as long as the resist is undamaged.
11. Remove the resist. I use lacquer thinners again on a paper towel. Once the resist has been removed, inspect the copper traces for breaks where the etchant ate the copper away where you wanted it. If the resist failed, you will see pink copper. At this point you can tin plate the traces, or solder plate it using liquid solder flux and solder wick with some solder. You could also paint the areas where solder doesn't go with a sealing type pen or nail polish.
12. Stuff the new PCB(s) and remount them onto the heat sink.
13. Follow your power up procedure.
I have recreated PCBs for hacked equipment over the years. It's expensive, but there are times that this would be the only reliable repair. Trace damage or broken PCBs are the two reasons a new board is made.
Good luck with this one. I feel you are on the right track by making a new circuit board from what you describe.
-Chris
Anatech,
i actually do have a hard copy of the 1300dc service manual, so i won't be flying so blind there.
otherwise, great info in that last post (ought to be a permanent post somewhere). i was wondering if it might be possible to use the board graphic from the service manual by scanning it into photoshop, erasing the component symbols and printing it out onto a media that would make a mask.
as far as your other suggestions go, i'll have to get back to you after i open the amp up again. i do know that q711 and q712 were completely enclosed packages, so i don't think there's any danger of a short to q713 and q714 even if insulators aren't present. further, the schematic from the service manual shows that q711 and q714, along with q712 and q713, have collectors that are directly connected, so even if there was a short through the heatsink, it would just open up another path for the circuit already in play.
in the meantime, here's a board shot i took of the left channel on the 1300dc a few months ago when it stopped working. steel yourself. you'll be able to see the copper wire that was soldered to fix the damaged trace on the left half of the board.
i actually do have a hard copy of the 1300dc service manual, so i won't be flying so blind there.
otherwise, great info in that last post (ought to be a permanent post somewhere). i was wondering if it might be possible to use the board graphic from the service manual by scanning it into photoshop, erasing the component symbols and printing it out onto a media that would make a mask.
as far as your other suggestions go, i'll have to get back to you after i open the amp up again. i do know that q711 and q712 were completely enclosed packages, so i don't think there's any danger of a short to q713 and q714 even if insulators aren't present. further, the schematic from the service manual shows that q711 and q714, along with q712 and q713, have collectors that are directly connected, so even if there was a short through the heatsink, it would just open up another path for the circuit already in play.
in the meantime, here's a board shot i took of the left channel on the 1300dc a few months ago when it stopped working. steel yourself. you'll be able to see the copper wire that was soldered to fix the damaged trace on the left half of the board.
An externally hosted image should be here but it was not working when we last tested it.
Hi mechanicalman,
Have you ever worked on a scan in Photoshop? This will take hours and hours to do. Then you still have no idea if the length and width are dimensioned properly. Then try to get the dimensions right.
-Chris
If you feel like messing with scale and stuff like that. To be honest with you, drilling using the original PCB as a guide ensures everything fits and is positioned exactly right.
Have you ever worked on a scan in Photoshop? This will take hours and hours to do. Then you still have no idea if the length and width are dimensioned properly. Then try to get the dimensions right.
Good. I used to have all the Marantz manuals. Now, I don't. Miss them.
Haven't looked, I just wanted to warn you since I have seen other technicians make that error. Bang.
I'm impressed. Someone went to a lot of work to do a scary job. The rest of the PCB doesn't look too bad, but I do see many bad solder joints. See the solder balls? Don't do that. Remove the old solder and redo the connection.
-Chris
kind of an afterthought (not that this thread hasn't been totally derailed with topics not pertinent to the original post), but when my 1300dc was working, i noticed that the right channel would cut out intermittently. i originally thought this might be dirty selector switches, but the cutout would occur regardless of input. i then noticed that it seemed to be connected to how the chassis was flexed or stressed. if i put pressure down on the back right corner, the channel cut out. if i shimmed it up with some sheets of paper it came back.
the symptoms were more pronounced if i lifted it up from opposite corners. it would come back if i lifted it up the other way.
is this typical of one kind of problem? (wire break, cracked pcb, dirty switch) it's a really delicate symptom. sometimes i could bring the channel back just by pushing on the front face with pressure from one finger.
the symptoms were more pronounced if i lifted it up from opposite corners. it would come back if i lifted it up the other way.
is this typical of one kind of problem? (wire break, cracked pcb, dirty switch) it's a really delicate symptom. sometimes i could bring the channel back just by pushing on the front face with pressure from one finger.
for sure
one of your contacts is not clean enough ...... one soldering somewere is loose ....one cable is stressed .....or a combination of the above ....
you have to look carefully ...often a vintage repair or upgrade doesnt finish with a few caps and a few transistors .....
tips :
1) if your thing is a cable issue you may operate your amp with your cover open ( always keep a safety lamp conected through the mains ) as discribed in the manual or many other posts in the forum ..... and start shaking cables here and there .....carefully and shake means move them a bit not rip them off !!!!
2) if this amp features a relay in the output this might be dirty or deff. use a quite heavy screw driver and hit the relay with it to see if sound is going to stop ....replace if needed .....
3) if this has no effect another trick to test your soldering is hot air ..... you may use a blowdryer of your gilfriend or wife to warm up the pcb from soldering side .....if you have any dry joints or loose ones the heat from the hair dryer will make them open and then sound is going to stop ....make always one small area at the time and since hair dyier doesnt produce that much heat you may have to spend a minute to warm up a specific area ....
often a good and carefull look and you will see suspicious soldering ....re do them any way ...... carefull not to solder two things together and youre done !!!!
regards sakis
one of your contacts is not clean enough ...... one soldering somewere is loose ....one cable is stressed .....or a combination of the above ....
you have to look carefully ...often a vintage repair or upgrade doesnt finish with a few caps and a few transistors .....
tips :
1) if your thing is a cable issue you may operate your amp with your cover open ( always keep a safety lamp conected through the mains ) as discribed in the manual or many other posts in the forum ..... and start shaking cables here and there .....carefully and shake means move them a bit not rip them off !!!!
2) if this amp features a relay in the output this might be dirty or deff. use a quite heavy screw driver and hit the relay with it to see if sound is going to stop ....replace if needed .....
3) if this has no effect another trick to test your soldering is hot air ..... you may use a blowdryer of your gilfriend or wife to warm up the pcb from soldering side .....if you have any dry joints or loose ones the heat from the hair dryer will make them open and then sound is going to stop ....make always one small area at the time and since hair dyier doesnt produce that much heat you may have to spend a minute to warm up a specific area ....
often a good and carefull look and you will see suspicious soldering ....re do them any way ...... carefull not to solder two things together and youre done !!!!
regards sakis
Hi mechanicalman,
Those have an automatic switch in the main in jack on the rear panel. Connect a jumper between them to test that out first. Most people don't realize that switch is there. Hint: No loops.
All those Marantz units had switch problems. I have two ailing 3650 preamps and an SC-9 preamp, plus an 1180DC. All suffering from various switch contact problems. They have been cleaned numerous times with various "fantastic" cleaning solutions. I suspect that the plating came off the base metal quickly. What a waste! Fantastic circuitry and crappy switches. I am seriously considering a modification to relays. A mammoth job.
The speaker output relay may need cleaning or replacement. If the contacts are not arced you can clean them. They are toast if arced.
How to test the other things?
Run a sine wave about 400 Hz to 1 KHz at a low level. to your speakers. Slowly actuate each switch in sequence, noting whether these are noisy or not (more than one is common). Rotate each control slowly and listen for noise, your tone controls need to be engaged for this test.
To check the speaker output relay, remove the top cover (power is off for this). Use a plastic toothbrush and tap the relay lightly, then more strongly while listening for noise. The conditions of the test are the same as above. If your signal level is too high, the fault may not occur.
-Chris
Those have an automatic switch in the main in jack on the rear panel. Connect a jumper between them to test that out first. Most people don't realize that switch is there. Hint: No loops.
All those Marantz units had switch problems. I have two ailing 3650 preamps and an SC-9 preamp, plus an 1180DC. All suffering from various switch contact problems. They have been cleaned numerous times with various "fantastic" cleaning solutions. I suspect that the plating came off the base metal quickly. What a waste! Fantastic circuitry and crappy switches. I am seriously considering a modification to relays. A mammoth job.
The speaker output relay may need cleaning or replacement. If the contacts are not arced you can clean them. They are toast if arced.
How to test the other things?
Run a sine wave about 400 Hz to 1 KHz at a low level. to your speakers. Slowly actuate each switch in sequence, noting whether these are noisy or not (more than one is common). Rotate each control slowly and listen for noise, your tone controls need to be engaged for this test.
To check the speaker output relay, remove the top cover (power is off for this). Use a plastic toothbrush and tap the relay lightly, then more strongly while listening for noise. The conditions of the test are the same as above. If your signal level is too high, the fault may not occur.
-Chris
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