Board sets appear on eBay typicallzy a couple times per year. Usually run $3-400.
I don’t find the boards in these all that fragile, but that depends on your soldering skills. Bench supply is a nice to have - rather easy to current limit the Technics supply too. Watch some YouTube videos on desoldering ICs - plenty of reasonable ways to accomplish that with wick and an iron.
I don’t find the boards in these all that fragile, but that depends on your soldering skills. Bench supply is a nice to have - rather easy to current limit the Technics supply too. Watch some YouTube videos on desoldering ICs - plenty of reasonable ways to accomplish that with wick and an iron.
A while back I found a complete set of boards on ebay, from a trusty seller in Japan, think it was samourai-electronics, may not be still available, cost was around 500-700U$ if i remembered correctly. But you may ask him if he has any in stock, is a reliable seller as far as I know.
I tried first with TTL-LS but it didn't work, probably because i was mixing DTL and TTL. I tried first to replace only a few chips. It may work if we replace all of them at once, but what worry me is the resistors and caps used all around in the signal path, to mix signals, change shapes, etc. Since the output current and output configuration is not the same as TTL, I would expect some strange behavior. As the guy reported some strange, intermittent glitches, that may be why. Some of these resistor/caps may need value adjustment to work with TTL. Also some IC are driving directly transistors in other sections of the circuit, again not sure that the TTL-LS can do it properly... The guys also reported that the start doesn't work well, it is because he doesn't use DTL. i had the same problem with the first TTL-LS I used, again R-C mismatch with the TTL chip...
What is fragile on these boards are the bad plated throught holes, really from an other area. If you don't take care, and put back a new IC, you may have none connected top and bottom pads at some locations. Since the IC are dead anyway and cannot be salvaged, better not take any chances and cut them out... The ic pin holes diameter are also very thight, not much space left to suck the solder out. They remind me of Philips scope pcb I used to work on, 35 years ago, pretty bad pcb, not like the excellent ones produce today.
Sorry i cannot do the repair for you at this time, i have full of others projects, and it will be expensive...
Try ebay first, but make sure it is a trusty seller, so you don't end up with an other defective pcb...
I tried first with TTL-LS but it didn't work, probably because i was mixing DTL and TTL. I tried first to replace only a few chips. It may work if we replace all of them at once, but what worry me is the resistors and caps used all around in the signal path, to mix signals, change shapes, etc. Since the output current and output configuration is not the same as TTL, I would expect some strange behavior. As the guy reported some strange, intermittent glitches, that may be why. Some of these resistor/caps may need value adjustment to work with TTL. Also some IC are driving directly transistors in other sections of the circuit, again not sure that the TTL-LS can do it properly... The guys also reported that the start doesn't work well, it is because he doesn't use DTL. i had the same problem with the first TTL-LS I used, again R-C mismatch with the TTL chip...
What is fragile on these boards are the bad plated throught holes, really from an other area. If you don't take care, and put back a new IC, you may have none connected top and bottom pads at some locations. Since the IC are dead anyway and cannot be salvaged, better not take any chances and cut them out... The ic pin holes diameter are also very thight, not much space left to suck the solder out. They remind me of Philips scope pcb I used to work on, 35 years ago, pretty bad pcb, not like the excellent ones produce today.
Sorry i cannot do the repair for you at this time, i have full of others projects, and it will be expensive...
Try ebay first, but make sure it is a trusty seller, so you don't end up with an other defective pcb...
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I'll look into the DTL chip replacements. Do you have replacement part numbers? Or, replace with original parts?
Also, can you folks recommend a good bench supply? I looked into these, and the ones that can do dual channels, have a 32.5V capability, and current limiting are expensive. Most are limited to 30V. At least the ones I'm seeing. I'm in the bay area, so there are surplus stores around. I can check there.
Any recommendations for sharp cutters for the chip legs?
And is a desoldering station recommended, or a manual vacuum pump is OK? There are some cheapies on ebay at <$50. Would those work? I hate to buy specialized equipment that I likely won't use again.
Also, can you folks recommend a good bench supply? I looked into these, and the ones that can do dual channels, have a 32.5V capability, and current limiting are expensive. Most are limited to 30V. At least the ones I'm seeing. I'm in the bay area, so there are surplus stores around. I can check there.
Any recommendations for sharp cutters for the chip legs?
And is a desoldering station recommended, or a manual vacuum pump is OK? There are some cheapies on ebay at <$50. Would those work? I hate to buy specialized equipment that I likely won't use again.
A cheap desolder pump is going to cause headache, heartburn, and more damage. You need a really good desolder station, or a pistol type, depending on which you like holding better. Don't skimp, if you do the cost of the cheap one is just going to get added to the good one.
You need 2 bench supplies, one for the logic 5v and the motor power 32.5v. They need to be individually switchable, as the logic voltage must be on before the motor voltage is applied.
Or repair your current supply and use that.
You need 2 bench supplies, one for the logic 5v and the motor power 32.5v. They need to be individually switchable, as the logic voltage must be on before the motor voltage is applied.
Or repair your current supply and use that.
6L6, I don't know if you've been following my problems over the last few pages, but it appears the PS is actually fine. Algar recommended a bench supply for testing by using the current limiting feature of the bench supply to test as I go along replacing individual chips. I agree I do need a bench supply (just generally for diy), but lab-grade ones tend to be expensive, and those that can do 30+V are rare and even more expensive.
Wow, what an incredible thread!
I recently acquired an SL-1000MKIIP previously used by the Swedish Radio. I assume identical to the version in post #892. It works great, however im having few issues I wanted to hear others thoughts on.
1. The start/stop button on the unit itself does not work, i have to press the 'remote' button on the control unit SH-10C to stop and repress it to start spinning. Presumebly boradcasting versions are set up this way, however I would like the get the normal button working. it appears to be in good condition so i don't think it is broken. I enclose a picture on how it is wired up in my unit. As you can see i have a white/red cable going from the start button to CN202 on the logic PCB. Im wondering if these rather should be connected somewhere else as I haven't seen it like this before.
2. I noticed when connected that the pickup is slightly skewed to the left. Is this normal or is it a problem? I played a few test records and I haven’t notice any tracking errors.
3. The headshell I got with the unit has what appears two resistors soldered (marked n10). What is the purpose of this? I haven't tried to hook up a pickup to it.
IMG 20180930 214027 — imgbb.com
IMG 20180927 100025 01 — imgbb.com
IMG 20180930 212431 — imgbb.com
IMG 20180930 231809 — imgbb.com
Best
I recently acquired an SL-1000MKIIP previously used by the Swedish Radio. I assume identical to the version in post #892. It works great, however im having few issues I wanted to hear others thoughts on.
1. The start/stop button on the unit itself does not work, i have to press the 'remote' button on the control unit SH-10C to stop and repress it to start spinning. Presumebly boradcasting versions are set up this way, however I would like the get the normal button working. it appears to be in good condition so i don't think it is broken. I enclose a picture on how it is wired up in my unit. As you can see i have a white/red cable going from the start button to CN202 on the logic PCB. Im wondering if these rather should be connected somewhere else as I haven't seen it like this before.
2. I noticed when connected that the pickup is slightly skewed to the left. Is this normal or is it a problem? I played a few test records and I haven’t notice any tracking errors.
3. The headshell I got with the unit has what appears two resistors soldered (marked n10). What is the purpose of this? I haven't tried to hook up a pickup to it.
IMG 20180930 214027 — imgbb.com
IMG 20180927 100025 01 — imgbb.com
IMG 20180930 212431 — imgbb.com
IMG 20180930 231809 — imgbb.com
Best
n10 are 100pF loading capacitors for moving magnet cartridges.
For the start stop you will need to go through this with a scope and the service manual. It would help if you have the SH-10C circuit, but I think you could do it without that.
For ra7 you did ask about PSU's hence 6L6's reply. eBay is what you need and I would not recommend surplus at all. You may need to get more experience before atmpting this though ?
For the start stop you will need to go through this with a scope and the service manual. It would help if you have the SH-10C circuit, but I think you could do it without that.
For ra7 you did ask about PSU's hence 6L6's reply. eBay is what you need and I would not recommend surplus at all. You may need to get more experience before atmpting this though ?
Thanks to JP, I contacted Samurai Electronics on Ebay and he was able to find me replacement boards (a full set), which are now on the way. It was almost the same cost as getting a Hakko FR301 and the replacement chips. Plus several hours of board surgery with a good chance that it still won't work. I figured spending a little extra on another set of boards is well worth it.
Now, how do I proceed with the replacement boards? Just connect the motor to the set of new boards? The PS appears to be fine, but are there any other no-load tests I should be doing before connecting it up?
Now, how do I proceed with the replacement boards? Just connect the motor to the set of new boards? The PS appears to be fine, but are there any other no-load tests I should be doing before connecting it up?
If you're not experienced in electronic I would not suggest you test your new PCB set outside of the turntable, with an external supply, too risky to damage the replacement board. BTW the 5V supply goes at different places on the digital board, and you need the external motherboard to connect everywhere. So again don't try it, you can damage the new board!
I would suggest you just replace the defective digital board, with the replacement one, into the SP-10, using the normal Technics power supply (make sure you have a good power supply to start with!), you should have 5V on one of the supply connector pin.
Your defective digital board is only used for the timing generation and the strobe, mainly, so you won't damage it, even if some others boards are not perfect... In mine only the digital one was toasted. The other boards use an other supply, as welll as the drive circuit to the turntable motor coils...
SB
I would suggest you just replace the defective digital board, with the replacement one, into the SP-10, using the normal Technics power supply (make sure you have a good power supply to start with!), you should have 5V on one of the supply connector pin.
Your defective digital board is only used for the timing generation and the strobe, mainly, so you won't damage it, even if some others boards are not perfect... In mine only the digital one was toasted. The other boards use an other supply, as welll as the drive circuit to the turntable motor coils...
SB
Right.
My deck went wrong tonight. Sudden speed wobble and horrible scratchy noise. Strobe all over and speed poor.
I swapped to my spare power supply and all is well (though the strobe light flickers using the spare).
Thankfully this seems to prove it’s the power supply not he motor unit! A further failsafe test was to plug in my spare sp10 and the same happened. Bad noise and speed. Must be the supply!
Guessing the fix is to recap and test the voltage rails?
If so, anyone point me to the list of caps I need? A mate can then order for me from the usual suppliers?
Anything else I’m missing here? I’ll recap both eventually but glad I didn’t sell on my second set quickly!
Thanks
My deck went wrong tonight. Sudden speed wobble and horrible scratchy noise. Strobe all over and speed poor.
I swapped to my spare power supply and all is well (though the strobe light flickers using the spare).
Thankfully this seems to prove it’s the power supply not he motor unit! A further failsafe test was to plug in my spare sp10 and the same happened. Bad noise and speed. Must be the supply!
Guessing the fix is to recap and test the voltage rails?
If so, anyone point me to the list of caps I need? A mate can then order for me from the usual suppliers?
Anything else I’m missing here? I’ll recap both eventually but glad I didn’t sell on my second set quickly!
Thanks
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