Whenever possible yes. The aerosol can doesn't have very good control, and can make a mess when trying to do things such as rotary and slide switches.
Certainly not the easiest, You access controls from the bottom.
Pioneer SX-737 rebuild BOM
- Thread starter loweran
- Start date
Certainly not the easiest, You access controls from the bottom.
In order to properly access them you need to take the board loose then turn it upward, just as one would if they needed to remove components from the board.
loweran
Super Member
DBT built. I tested it on a radio I have in the garage. I put a 100w bulb in. Radio worked, bulb did not light. So, I hooked it up to my chop saw. Bright light, saw did not turn. Seems like a good test.
Hooked up the receiver to it, Light briefly lite and went out. Receiver stayed on. Turned off and on again, light did not light. I think maybe 100w is too much. I was concerned the bulb went out so I hooked it up to the toaster and it light brightly.
Plugged the receiver into the wall. Powered up fine. Now I need to get the speakers hooked up.
Hooked up the receiver to it, Light briefly lite and went out. Receiver stayed on. Turned off and on again, light did not light. I think maybe 100w is too much. I was concerned the bulb went out so I hooked it up to the toaster and it light brightly.
Plugged the receiver into the wall. Powered up fine. Now I need to get the speakers hooked up.
loweran
Super Member
Update: Right channel was fine. My woofer is messed up. That will be a topic for another board. I swapped it out with my other pair of 602s and it was clear.
I played some music off my phone on the AUX input and let it warm up. All of a sudden, WHAM and no sound. I powered down then back up. Loud popping in the left channel.
Took the phone off and turned the volume all the way down. Powered up, still popping.
I played some music off my phone on the AUX input and let it warm up. All of a sudden, WHAM and no sound. I powered down then back up. Loud popping in the left channel.
Took the phone off and turned the volume all the way down. Powered up, still popping.
The 100 watt bulb is fine. Under normal conditions the bulb may illuminate a bit just briefly due to the surge current, until the main power supply caps charge up.
Need to isolate what section of the receiver is actually generating the noise. On some units you can simply pull the pre/out to main/ in jumpers on the back.
But your unit doesn't have those jacks, so the pre amp and main amp would need to be separated internally. If the unit is still doing the same thing after they are separated, then you know the noise is being generated in the main amp section. Just for testing purposes, it would be wise to round up a set of speakers that are expendable in case something goes wrong. You wouldn't want to screw up a good set of speakers testing an amp which might have issues.
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If you're going to rebuild you wouldn't need to spend a bunch of time tracing the fault down the components responsible. But it wouldn't be a bad idea to at least
know which "section" of the receiver is causing the issue. Desoldering connecting pins 7 and 15 on the main amp board will separate both channels. Don't unwrap the
wire from the pins, just desolder the whole pin with the wire connected from the board. BTW once you're ready to actually rebuild the board, if you wish you can go ahead and desolder all of the posts so that you can fully separate the board from the receiver. Makes it a lot nicer to work with on the bench that way. Plus it will help keep the wire from being flexed back and fourth to the point where they end up getting broken from their posts. It is solid core wire so its easier to break.
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loweran
Super Member
Glen, I want to say thanks for all your help so far and also to the other members who have chimed in.
I don't quite understand the test described above both logically and mechanically. If I separate the pre from the main, do I power up with speakers and see if the popping is still there? I assume there would be no input, just amplification. I would need to let it warm up too. Is this correct?
On the pins, if I de-solder from underneath? Will the wire stay intact with the pin?
Lastly, as I put my parts list together, I thought about skipping the mic and the tuner. Should I just replace the two tuner transistors though? If I do that will it need to be aligned?
I don't quite understand the test described above both logically and mechanically. If I separate the pre from the main, do I power up with speakers and see if the popping is still there? I assume there would be no input, just amplification. I would need to let it warm up too. Is this correct?
On the pins, if I de-solder from underneath? Will the wire stay intact with the pin?
Lastly, as I put my parts list together, I thought about skipping the mic and the tuner. Should I just replace the two tuner transistors though? If I do that will it need to be aligned?
Ok first the logic, The noise you speak of can potentially be a result of an issue in "both" the preamp and power amp section of the receiver. However much of the time
it's usually one or the other. If you separate the preamp from the amp section and it's still popping over the speakers the way it was, then you know the the noise is being
generated by the power amp section itself. Why? because the preamp is no longer connected to the power amp, and therefore cannot feed any noise into it, which would in turn come over the speakers. Separating the two sections is simply just using the process of elimination, to narrow down the area where the problem really exists.
Next the mechanics,
To start with, the non soldered connections are made to the posts with an old but reliable method called wire wrap.
https://en.wikipedia.org/wiki/Wire_wrap
This method has proven to make reliable connections. However you don't dare unwrap and try to re-wrap it using the same stripped
portion of wire. You won't get a good connection. Also the wire isn't long enough to strip it back to do the connection over. Plus it takes
a special tool to do it right anyway. So then the question becomes, how does one remove a board without messing up the wire wrap?
Well the posts which the wires are wrapped to are just soldered to the PC board. Instead of unwrapping the connections simply un-solder the pin itself
from the board with the wire still attached to it, then you can solder it back when its time to reconnect it.
Yes, The wire is wrapped tightly, and should be fine provided you don't attempt to unwrap the post.
Unless there is an issue with the tuner relating to them, best to just leave them alone.
loweran
Super Member
OK, I am getting my BOM ready for an order. It would be awesome if I could get this up and running by Christmas, but not sure time will permit. I still need to get my soldering skills in check. Seems I donated most of my old electronics that I don't use (VCRs, etc) so I need to find a practice vehicle.
There is one part from Mark's list that is obsolete: http://www.mouser.com/Search/Produc...334virtualkey59850000virtualkey598-DSF050J334
They have this one that is 10% vs 5%: http://www.mouser.com/ProductDetail/Nichicon/UKL1HR33KDDANA/?qs=AU7cqTtHTl7AXFUiok7TRQ==
Not sure this would be good or not. Can someone please help me find a suitable alternative. I am not sure what specs are most important. Mouser does not seem to have anything exact.
I also see the protection circuit relay is on the list. This one scares me a bit as I have read that replacements don't fit into the location. Also, to these solder to wires or to the board?
Lastly, should I replace the filter caps? I did not see them on the list.
There is one part from Mark's list that is obsolete: http://www.mouser.com/Search/Produc...334virtualkey59850000virtualkey598-DSF050J334
They have this one that is 10% vs 5%: http://www.mouser.com/ProductDetail/Nichicon/UKL1HR33KDDANA/?qs=AU7cqTtHTl7AXFUiok7TRQ==
Not sure this would be good or not. Can someone please help me find a suitable alternative. I am not sure what specs are most important. Mouser does not seem to have anything exact.
I also see the protection circuit relay is on the list. This one scares me a bit as I have read that replacements don't fit into the location. Also, to these solder to wires or to the board?
Lastly, should I replace the filter caps? I did not see them on the list.
loweran
Super Member
Mark, at the bottom of the list you say EDIT 1/2/2015 CHANGED trimpots to types 3386F and 3296Y.
I noticed that there are still two 3386Fs in the parts list. Where those meant to be changed to 3296Y?
That's not going to be enough time. Not trying to dump a load of pessimism on you, but need to be realistic.
If you are wanting to use the receiver as a gift, best to shoot for some future occasion.
I could stand to get rid of a couple old PC boards I have stashed away, could send you a couple. Just would need to PM your info to me.
You can use this one.
http://www.mouser.com/ProductDetail/Panasonic/ECQ-V1H334JL/?qs=sGAEpiMZZMv1cc3ydrPrF%2bfZ13WJ/r1/qiRpdSGFZEA=
The relay doesn't mount on a PC board, it's wired in circuit. Look at the pic I posted of the bottom earlier. You'll see the relay mounts on the bottom, sticking up through a hole in the chassis.
Yes, what's the diameter in millimeters and length.
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No, you would get two of each. The Y suffix is a 10k multi-turn pot which would replace the old single turn DC offset controls. The F suffix is a single turn version to replace the old bias control pots. They are not an exact drop in replacement but we'll get to that later.
loweran
Super Member
Yes, I think I am being optimistic.
I see now. Looks like four wires.
Thanks so much for the offer. I will find something around here to take apart and trash.
Not sure yet on the size of the filter caps. I thought I read somewhere here about replacement part numbers. I did not see them in the list Mark sent.
As I continue to read and research, I am thinking of picking up a Hakko FX888D for the job. I am worried I won't have enough experience to dial in the WLC-100. Not sure what the optimal temp should be. Seems like the Hakko would take away that part of the curve a bit.