It's good advice to resolder it from 100V to 117V, but that's a sketchy anecdote about VFDs! That's not what happens when you plug a 100V DEP-5 into 120V, and if it does you need to unplug it fast! The voltage to the display doesn't change when you run a 100V model on 120V - you can check with a multimeter. Those Roland PSU boards have +5V +15 -15V DC output rails, and the ones with VFDs have a +30V rail. The rails are regulated. I've soldered these PSUs, and I always check the output rails to make sure everything looks good, and the most I've seen a rail change after retapping it is 0.03V which is still well within spec. That 30V rail is spec'd at 30V-34V. The reason you want to resolder the taps is because running a 100V model on 120V power makes the voltage regulators run hotter. It will shorten the life of the PSU, and if it fails THEN it might fry something if a regulator shorts instead of just failing open. But '80s/'90s Rolands go decades without failing. Most people run 100V Rolands on 120V perpetually with no problems. They have huge heat sinks on the regulators. The only scenario for the glowing VFD filaments is: 1) You leave a 100V DEP-5 plugged into 120V power for several years 2) The 30V regulator is the first PSU component to fail. 3) The 30V regulator fails short and starts to burn. 4) You ignore the electrical fire / burning plastic smell and leave the DEP-5 on. 5) The 30V VFD is now getting about 60V of raw rectified DC from the transformer secondary winding. 6) The filaments glow red! 😯🔥🚒 I doubt it could last very long in that state before the PSU board completely burned and the capacitors popped and the whole thing died - and hopefully didn't burn the building down.
Yes WRT regulators running hot but also the main transformer will run hot and have reduced life. The VFD has a high voltage blanking cathode (the VFD is in fact a Triode with each digit having a Grid, and each segment being an Anode). The filament (cathode) supply is rectified and filtered but it is not regulated. (Grey wires straight from transformer, rectified, 470uF cap, to + - filament terminals), and the higher voltage Anode supply (+20V) is also unregulated. Maybe Roland changed this in a later revision but that's the unit I have and the schematics agree. Given that the filament only wants 1.7V at 80mA (according to SDE3000 service notes) I'm concerned about the filaments glowing ever so faintly orange before I made the transformer tap reconnection.
Thanks for this, I did a similar mod on my imported Roland GP-100. I'm not sure if the displays in 1996 were similar or not but at least I know it's running at 120v now. The wires were blue and yellow in the case of the GP-100 but often times you can find official repair manuals that list the wire colors and their specific regional configuration.
Nicely done! The LCD in the GP100 is a character display running off the 5V regulator. But you still want the transformer on the correct tap so it doesn't wear out ahead of time so still the right thing to do as you did!
Hey, I have a couple of SDE-3000's just wondering if i can convert the transformer inside to work on 220V as its currently 100V I know I could use a external step up/down transformer but would prefer to convert it internally. Thanks!
Unfortunately that requires a different transformer. The USA/Japan units are the ones that have a 100V/117V primary. For EU/AU you need the unit with the 220/240V transformer. You could possibly buy that as a spare part from your regional Roland service department, but given the age of the units it's not likely a stocked item anymore. You will most likely have to use a step-down transformer.
Thank you for sharing this! I have a SDE-3000 arriving soon from JP to try this on. Do you know if this same procedure applies to the SDE/SRV-330 power supplies? I've been looking for a reasonably priced SRV-330 and getting a 100v unit from JP appears to be the most cost effective.
It should. But the SRV/SDE-330 units are much newer - they might have switching power supplies and may even be universal (like your modern laptop adapter). One of these days I'll check them out.
Just examined the service notes. The service manual schematics and BOM indicate the Japan/US unit has a transformer for 100 and 117V just like the older units. Attach the blue tap for 117V or the white tap for 100V - so yes in short, this will work for the SDE/SRV-330 as well.
@@guitarrigguru something's wrong with the feedback loop, or the D/A A/D cycle. The delay "seems to work" but it has infinite feedback always and signals dont come out of the delay path. I couldn't get help from other locals technicians
@@camiloalvarez9850 My recommendation is to use the SDE3000 service manual (you can download from many places on the internet for free), and walk through the step-by-step measurements of the different test points that describe the signal path and A/D/A conversion. Start with a sine wave signal input and trace the signal with your oscilloscope from the jack all the way to the AD converter. The feedback path in the SDE3000 is analog (like early BOSS DD-2) so you can (referring to the schematic) short the middle of the feedback signal to ground and if you are still hearing noise or squeeling from the delay output, then you probably have bad DRAM chips causing noise. I hope that helps. I'd offer to look at it for you but I suspect the cost of shipping the unit to me and back to you is more than it would be worth to just buy another one off ebay.
I have two Roland SDE-3000'S 100V. Will just swapping the Blue and Green be enough to safely run it on 117V? At the moment Blue and White are connected to mains (white is middle and green in connected to lower terminal/nothing. When unit is turned on BLUE reads 120V and GREEN reads about 139V. Thank you in advance.
I have an SDE300-A and did this, yes it will work. The way to know for certain is that after swapping Blue and Green, the green will be at mains 120V and the blue will measure around 100V since that's the transformer tap for Japanese mains voltage.
There's no good way to do this other than to buy the replacement transformer for Roland's original export model. That would probably cost more than it's worth. However, you *could* just run it off a 50W step-down autotransformer, which is economical, *or* a 110V output inverter from a 12V DC power supply. If you were an Electronics Engineer/Tech and know what you're doing you could take the factory transformer out and replace that with a separate unit. The tricky problem is that these typically have an additional transformer output winding for the heaters in the vacuum florescent display tube which needs to be about 6Vac, and isolated from the other windings (the display is actually a special type of Valve/Triode tube). If you're in Australia/NZ/UK/Europe a step-down autotransformer will be fine. I've been using a step-up for an ENGL rack preamp to run from my 110V outlet in the states.
Your video is on a DEP-5. On the SDE1000 the white wire is in the middle terminal. Do you just reverse the green and blue wires to convert to 117VAC on the SDE1000?
I have an SDE3000 I did this on, and yes I believe it's the same. But first, to be sure, measure the voltage with a multi-meter in AC 200V range. If you plug into mains and measure from the main input and neutral, you'll measure about 120V AC, and the other tap if it's set for Japan will measure higher, more than 130V. Then those would be the two wires you would swap. In my units, all three used the same transformer with the same wire colors so you should be good, but always measure first to be sure. (and please, don't shock yourself...)
Where was it shipped from? Within the US it is most likely going to be 117V, from Japan it's set to 100V but you can change it as in this video, but most of Europe and Asia is 220/230 and it's a different part number for the transformer. In that case you will need to get a step-up transformer (cheap on Amazon... )
I received it and its 117V, but as soon as I pushed the power button it pushed all the way in and stuck. I think the crazy power mechanism broke! So it did not power on...
@@anonymous_friend Yikes! So those are replaceable items. There's a plastic rod that connects the front-panel button to the switch which is on the power circuit board further back in the unit. It may just be jammed. Open the lid and take a look! (With the power cable unplugged of course!) If the rod is broken, call Roland and ask to order part no. 2214020700 (That's the long arm with two bends that links the front button to the power switch).
*Is that the same for the Boss SE 70 super effects??? I plugged it up for about an hour and man that thing was SO HOT on the bottom moreover. I got it in from japan...*
SE50/70 are completely DIFFERENT inside. But yes it's the same problem. Given the small size of those units I'm not sure they used a transformer with a tap for 120V. The only way to know is open it up. If you keep using a 100V unit on 120V it will eventually burn out the transformer. To get them the size they did back then, before switching supplies were a thing, they designed the power transformers to be right on the edge of saturation at 60Hz. So it is working, but saturating slightly, which means excessive current in the windings, which means excessive heat and eventual demise.
@@schematica Doesn't the SE50/70 use a power adapter. 12 Volts if I recall? Correct me if I am wrong, but the problem of 100v/120v would not be an issue like what is explained in the video above.
@@botany500kojak LOL yeah I have two SE-70s from Japan, and it's irrelevant because the power bricks put out 12V AC. A lot of this stuff gets kinda hot. The SRV-3030 gets a lot hotter than the SE-70.
It's good advice to resolder it from 100V to 117V, but that's a sketchy anecdote about VFDs! That's not what happens when you plug a 100V DEP-5 into 120V, and if it does you need to unplug it fast!
The voltage to the display doesn't change when you run a 100V model on 120V - you can check with a multimeter.
Those Roland PSU boards have +5V +15 -15V DC output rails, and the ones with VFDs have a +30V rail. The rails are regulated. I've soldered these PSUs, and I always check the output rails to make sure everything looks good, and the most I've seen a rail change after retapping it is 0.03V which is still well within spec. That 30V rail is spec'd at 30V-34V.
The reason you want to resolder the taps is because running a 100V model on 120V power makes the voltage regulators run hotter. It will shorten the life of the PSU, and if it fails THEN it might fry something if a regulator shorts instead of just failing open. But '80s/'90s Rolands go decades without failing. Most people run 100V Rolands on 120V perpetually with no problems. They have huge heat sinks on the regulators.
The only scenario for the glowing VFD filaments is:
1) You leave a 100V DEP-5 plugged into 120V power for several years
2) The 30V regulator is the first PSU component to fail.
3) The 30V regulator fails short and starts to burn.
4) You ignore the electrical fire / burning plastic smell and leave the DEP-5 on.
5) The 30V VFD is now getting about 60V of raw rectified DC from the transformer secondary winding.
6) The filaments glow red!
😯🔥🚒
I doubt it could last very long in that state before the PSU board completely burned and the capacitors popped and the whole thing died - and hopefully didn't burn the building down.
Yes WRT regulators running hot but also the main transformer will run hot and have reduced life. The VFD has a high voltage blanking cathode (the VFD is in fact a Triode with each digit having a Grid, and each segment being an Anode). The filament (cathode) supply is rectified and filtered but it is not regulated. (Grey wires straight from transformer, rectified, 470uF cap, to + - filament terminals), and the higher voltage Anode supply (+20V) is also unregulated. Maybe Roland changed this in a later revision but that's the unit I have and the schematics agree. Given that the filament only wants 1.7V at 80mA (according to SDE3000 service notes) I'm concerned about the filaments glowing ever so faintly orange before I made the transformer tap reconnection.
Thanks for this, I did a similar mod on my imported Roland GP-100. I'm not sure if the displays in 1996 were similar or not but at least I know it's running at 120v now. The wires were blue and yellow in the case of the GP-100 but often times you can find official repair manuals that list the wire colors and their specific regional configuration.
Nicely done! The LCD in the GP100 is a character display running off the 5V regulator. But you still want the transformer on the correct tap so it doesn't wear out ahead of time so still the right thing to do as you did!
That is why I own a line voltage adjuster.
bought an sde-3000 running it on a variac at 100v so no issue there. It was initially sounding great but now has a loud pop every 15 seconds.
Hey, I have a couple of SDE-3000's just wondering if i can convert the transformer inside to work on 220V as its currently 100V I know I could use a external step up/down transformer but would prefer to convert it internally.
Thanks!
Unfortunately that requires a different transformer. The USA/Japan units are the ones that have a 100V/117V primary. For EU/AU you need the unit with the 220/240V transformer. You could possibly buy that as a spare part from your regional Roland service department, but given the age of the units it's not likely a stocked item anymore. You will most likely have to use a step-down transformer.
Would you happen to know the difference between the Roland "SDE-3000" and the "SDE-3000A?"
I've bought a SDE-3000 and it worked for a bit but then the output started to distort. Any tips on how to fix this?
Thank you!!!
Thank you for sharing this! I have a SDE-3000 arriving soon from JP to try this on. Do you know if this same procedure applies to the SDE/SRV-330 power supplies? I've been looking for a reasonably priced SRV-330 and getting a 100v unit from JP appears to be the most cost effective.
It should. But the SRV/SDE-330 units are much newer - they might have switching power supplies and may even be universal (like your modern laptop adapter). One of these days I'll check them out.
Just examined the service notes. The service manual schematics and BOM indicate the Japan/US unit has a transformer for 100 and 117V just like the older units. Attach the blue tap for 117V or the white tap for 100V - so yes in short, this will work for the SDE/SRV-330 as well.
This is gamechanging information bruh, thank you for sharing!@@schematica
For the SRV/SDE-330 you just swap the blue/yellow wires connected to the "502" and "503" pads to switch between 100V and 117V.
Hi there! I'm a service technician from Argentina and I'm having trouble repairing an SDE3000, can you help me?
What's the problem?
@@guitarrigguru something's wrong with the feedback loop, or the D/A A/D cycle. The delay "seems to work" but it has infinite feedback always and signals dont come out of the delay path. I couldn't get help from other locals technicians
@@camiloalvarez9850 My recommendation is to use the SDE3000 service manual (you can download from many places on the internet for free), and walk through the step-by-step measurements of the different test points that describe the signal path and A/D/A conversion. Start with a sine wave signal input and trace the signal with your oscilloscope from the jack all the way to the AD converter. The feedback path in the SDE3000 is analog (like early BOSS DD-2) so you can (referring to the schematic) short the middle of the feedback signal to ground and if you are still hearing noise or squeeling from the delay output, then you probably have bad DRAM chips causing noise. I hope that helps. I'd offer to look at it for you but I suspect the cost of shipping the unit to me and back to you is more than it would be worth to just buy another one off ebay.
I have two Roland SDE-3000'S 100V. Will just swapping the Blue and Green be enough to safely run it on 117V? At the moment Blue and White are connected to mains (white is middle and green in connected to lower terminal/nothing. When unit is turned on BLUE reads 120V and GREEN reads about 139V. Thank you in advance.
I have an SDE300-A and did this, yes it will work. The way to know for certain is that after swapping Blue and Green, the green will be at mains 120V and the blue will measure around 100V since that's the transformer tap for Japanese mains voltage.
@@schematica And that's it? No need to do anything else? Thank you for replying.
@@berumen_guitars Yes.
Any idea which colour wire it would be on the SDE 3000? Is it the same as this one?
Blue and green normally. See the comments below between me and Isaac Berumen.
Hi, I want to mod SDE3000 from 100v to 220v. Is there a way to do it?
There's no good way to do this other than to buy the replacement transformer for Roland's original export model. That would probably cost more than it's worth. However, you *could* just run it off a 50W step-down autotransformer, which is economical, *or* a 110V output inverter from a 12V DC power supply. If you were an Electronics Engineer/Tech and know what you're doing you could take the factory transformer out and replace that with a separate unit. The tricky problem is that these typically have an additional transformer output winding for the heaters in the vacuum florescent display tube which needs to be about 6Vac, and isolated from the other windings (the display is actually a special type of Valve/Triode tube). If you're in Australia/NZ/UK/Europe a step-down autotransformer will be fine. I've been using a step-up for an ENGL rack preamp to run from my 110V outlet in the states.
Your video is on a DEP-5. On the SDE1000 the white wire is in the middle terminal. Do you just reverse the green and blue wires to convert to 117VAC on the SDE1000?
I have an SDE3000 I did this on, and yes I believe it's the same. But first, to be sure, measure the voltage with a multi-meter in AC 200V range. If you plug into mains and measure from the main input and neutral, you'll measure about 120V AC, and the other tap if it's set for Japan will measure higher, more than 130V. Then those would be the two wires you would swap. In my units, all three used the same transformer with the same wire colors so you should be good, but always measure first to be sure. (and please, don't shock yourself...)
@@schematica Thanks for the feedback. It is the same. I just swapped the blue and green and works and tests perfectly. Thanks again!
@@schematica *Does this also apply for the Boss SE70?*
@@officialpoa3171 no.
Cant figure out how the bypass switch works on this one?
I still have to fix one for a friend! I should video as a follow-up... so many videos to edit, so little time!
I just bought a DEP-5 without knowing what voltage it is. I'm in the US. If it is 220V can it be changed to 117V easily? Thanks
Where was it shipped from? Within the US it is most likely going to be 117V, from Japan it's set to 100V but you can change it as in this video, but most of Europe and Asia is 220/230 and it's a different part number for the transformer. In that case you will need to get a step-up transformer (cheap on Amazon... )
I received it and its 117V, but as soon as I pushed the power button it pushed all the way in and stuck. I think the crazy power mechanism broke! So it did not power on...
@@anonymous_friend Yikes! So those are replaceable items. There's a plastic rod that connects the front-panel button to the switch which is on the power circuit board further back in the unit. It may just be jammed. Open the lid and take a look! (With the power cable unplugged of course!) If the rod is broken, call Roland and ask to order part no. 2214020700 (That's the long arm with two bends that links the front button to the power switch).
im.SDE 1000.roland ..mau saya jual..masih mulus
*Is that the same for the Boss SE 70 super effects??? I plugged it up for about an hour and man that thing was SO HOT on the bottom moreover. I got it in from japan...*
SE50/70 are completely DIFFERENT inside. But yes it's the same problem. Given the small size of those units I'm not sure they used a transformer with a tap for 120V. The only way to know is open it up. If you keep using a 100V unit on 120V it will eventually burn out the transformer. To get them the size they did back then, before switching supplies were a thing, they designed the power transformers to be right on the edge of saturation at 60Hz. So it is working, but saturating slightly, which means excessive current in the windings, which means excessive heat and eventual demise.
@@schematica Doesn't the SE50/70 use a power adapter. 12 Volts if I recall? Correct me if I am wrong, but the problem of 100v/120v would not be an issue like what is explained in the video above.
@@botany500kojak LOL yeah I have two SE-70s from Japan, and it's irrelevant because the power bricks put out 12V AC. A lot of this stuff gets kinda hot. The SRV-3030 gets a lot hotter than the SE-70.