Hi, I bought a dead Vermon ER9 and I'm trying to work out the PSU voltages. If anybody has one could they kindly measure what the voltages are eminating from the PSU. I've got 20 volts AC going in - the transformer seems to be working OK, but nothing coming out of the PSU. Does anyone know that the voltages should be? I intend to build a new PSU to hopefully bring the machine back to life. There's no info on the schematic I have.
The wires are as follow: Wires from left to right
Orange from transformer, green???
Black
NC
Yellow
Red
Brown
Orange from transformer
The wires are as follow: Wires from left to right
Orange from transformer, green???
Black
NC
Yellow
Red
Brown
Orange from transformer
IF the transformer is ok; why not repair the psu.
Disconnect al users whatever that may be (preamps, power amps, fx, etc whatever...)
Then, if that's ok reconnect the users one by one. But measure before and after each connection.
And write the voltages on a piece of paper.
And; let us have a look at the schematic...
Disconnect al users whatever that may be (preamps, power amps, fx, etc whatever...)
Then, if that's ok reconnect the users one by one. But measure before and after each connection.
And write the voltages on a piece of paper.
And; let us have a look at the schematic...
Hi Tarzan, Thanks for the help. The PSU isn't working. I've metered the voltages coming out and they are zero. O think they are meant to be +12v and +5 volts...but that's a conecture based on scraping bits of info from the internet. Here is a link to the schematic http://www.bleeps-and-peeps.com/ima...na/er_9/schematics/vermona er9 schematics.pdf
If you aren't fmiliar with the machine than here's a link to a vid showing it:
If you aren't fmiliar with the machine than here's a link to a vid showing it:
I had a look at the schematic. Indeed you need a 5V and a 12V supply.
The 5V is only needed for the logic part in module R12.
What about the currents?
For the 36 gates, I assume 4 gates in each IC = 12 IC's, wil need about 500mA.
The opamps, about the same.
So a 0.5A, 5V and 1A, 12V will do.
But if you have a bench PSU,you can test each module out of the unit by applying the needed voltage, being 5V or 12V and check the working of the unit.
Mesure the current for each module.
Now you know how much current is needed in total and rebuild the psu accordingly.
Then assemble everything and fire it up.
The 5V is only needed for the logic part in module R12.
What about the currents?
For the 36 gates, I assume 4 gates in each IC = 12 IC's, wil need about 500mA.
The opamps, about the same.
So a 0.5A, 5V and 1A, 12V will do.
But if you have a bench PSU,you can test each module out of the unit by applying the needed voltage, being 5V or 12V and check the working of the unit.
Mesure the current for each module.
Now you know how much current is needed in total and rebuild the psu accordingly.
Then assemble everything and fire it up.
It would possibly help to make a close up picture of its PSU so anyone reading can see what the problem can be. Just saying. A bit like troubleshooting as if it was on our bench and not yours.
Apologies for delay, been preoccupied with other stuff. Here are some pics of the PSU. I thinking I'll make a new one using perf board. A new bridge rectifier and some voltage regulators. Any thoughts? The exisiting board has some interesting componants which I've never seen before!
First measure voltages. Exactly the advice by Tarzan. First if AC is at the board and then the rectified DC voltage. If you have AC but no DC it may be a defective rectifier etc. If you have rectified and filtered DC but no voltage after the regulating transistor then that one may be defective.
Not familiar with electronic musical instruments but I have heard a few times that changing/modernizing devices may lead to it measuring better but with different sound. It maybe is essential to repair the original PSU.
Not familiar with electronic musical instruments but I have heard a few times that changing/modernizing devices may lead to it measuring better but with different sound. It maybe is essential to repair the original PSU.
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Wel, disconnect the power supply board from the connector.
Switch the unit on. Is there AC on the connector?
If yes; voltages are ...
Switch the unit off.
If they are as expected, connect the AC with some wires to the power supply board when it's still disconnected from the connector.
Switch the unit on.
Do you have any DC voltages?
Switch the unit off.
If not repair the board as explained by Jean-Paul.
Let us know...
Switch the unit on. Is there AC on the connector?
If yes; voltages are ...
Switch the unit off.
If they are as expected, connect the AC with some wires to the power supply board when it's still disconnected from the connector.
Switch the unit on.
Do you have any DC voltages?
Switch the unit off.
If not repair the board as explained by Jean-Paul.
Let us know...
Hi,
I have voltages. Basically, its a 220 to 20 volt AC/AC then rectified to +20, +12 and +5. The tempo light and tempo control seem to work. No sound comming our of jack so will start with drum cards and see which if any are woring then move on to amp. My gess since there's globally no sound it's the amp. I'll keep yuou posted.
I have voltages. Basically, its a 220 to 20 volt AC/AC then rectified to +20, +12 and +5. The tempo light and tempo control seem to work. No sound comming our of jack so will start with drum cards and see which if any are woring then move on to amp. My gess since there's globally no sound it's the amp. I'll keep yuou posted.
So the psu board is ok.
Now, test each board, one by one, and make sure it's ok.
Allways connect one board at the time and test it.
Then remove it from the connector and use another board.
Do this until all boards are tested and found ok.
Reassemble everything and it should work.
Unless some wires are disconnected.
Now, test each board, one by one, and make sure it's ok.
Allways connect one board at the time and test it.
Then remove it from the connector and use another board.
Do this until all boards are tested and found ok.
Reassemble everything and it should work.
Unless some wires are disconnected.
Thanks. I'll see if I can trace any audio coming from the boards - drums sound are grouped on a seperate boards. My bet is these are working and something has happened to the output amp since all sound go through one amp I'm led to beleive.
Hi, "My bet is these are working" is not a sure way that there are no problems in the boards.
"To measure is to know" is the ideology to folow. Make sure they (the drum boards) are all working as intended and then go on with the next, the output amp.
You can of course also do it in reverse and check the output amp first.
If that is working, test each board, one after the other.
I see you 'l get it back making sound.
Keep on going...
"To measure is to know" is the ideology to folow. Make sure they (the drum boards) are all working as intended and then go on with the next, the output amp.
You can of course also do it in reverse and check the output amp first.
If that is working, test each board, one after the other.
I see you 'l get it back making sound.
Keep on going...