JLM AUDIO

I just wanted to drop the 48V to 24V? The other supplies would be +/- 12V. I would use a 24VCT transformer?

soliton wrote:I just wanted to drop the 48V to 24V? The other supplies would be +/- 12V. I would use a 24VCT transformer?

OK easy one. You will still need the voltage doubler to get 24vdc with this low of ac volts (12vac - 0v - 12vac). So just build the AC/DC standard do NOT do any mods EXCEPT short out the R7 47R 1W. Set to Doubler/Tripler to Doubler. Set voltage rails to +/-12v and 24v and your done.

Hello everybody,

I have just finished my first diy preamp VP312DI, and the powerstation, but I have a problem.
The 317 regulator of +16v is very hot and the doa of vp312di to, exactly the transistor in +16v.
It happen only when the module is connected.
I have a 160v 2x24v 3.2A each. With the tester it mesures perfectly each rail with the module disconect( +-16,+-24,+48v )
Maybe ists a problem in the module.

Your products and builds are great,
Thanks

Piscolabis wrote:Hello everybody,

I have just finished my first diy preamp VP312DI, and the powerstation, but I have a problem.
The 317 regulator of +16v is very hot and the doa of vp312di to, exactly the transistor in +16v.
It happen only when the module is connected.
I have a 160v 2x24v 3.2A each. With the tester it mesures perfectly each rail with the module disconect( +-16,+-24,+48v )
Maybe ists a problem in the module.

If the power supply supplies the correct rail volts unloaded and loaded it is working correctly.

The problem has to be in the 312 module or wiring to the 312 module or the DOA on that module.

Your products and builds are great,
Thanks

Joe,

I am considering using a power station to provide + / - 15V DC (max 200ma each), and +5V DC (200ma max) to power up a AD converter evaluation board.

With a 15 - 0 - 15 transformer (I plugged in 18V in the calculator) the heatsink calculations are: 15V rails - about 45 C/W each, 5V - about 23 C/W, total - about 14 C/W

Do you think it will be adequate to bolt the regulators to the side of a 1RU case, or a strip of aluminium? Other suggestions?

Thanks! Paul

prhunt wrote:Joe,

I am considering using a power station to provide + / - 15V DC (max 200ma each), and +5V DC (200ma max) to power up a AD converter evaluation board.

With a 15 - 0 - 15 transformer (I plugged in 18V in the calculator) the heatsink calculations are: 15V rails - about 45 C/W each, 5V - about 23 C/W, total - about 14 C/W

Do you think it will be adequate to bolt the regulators to the side of a 1RU case, or a strip of aluminium? Other suggestions?

Thanks! Paul

Yes these high C/W ratings mean that very little heatsinking is needed. Short out C1 and C2 to disable the 48v doubler as shown under the AC/DC pcb (Note 3) so it can be used for the 5v rail easily. The side of the case or strip of aluminium will be perfect.

Just what I wanted to hear! Cheers Joe!

Paul

Hi!

I have a question regarding wiring of transformer, main switch, jlm acdc and power switch.

• I have a transformer like this
  http://www.selectronic.fr/transformateu ... ier-1.html
  Pri: 115V + 115V
  Sec: 24V + 24V
• a standard switch (like used for gobetween)
• an jlm acdc
• and a led, standard 2v drop

And it's for a dual GR MP-2 that takes +-24V and +48V


Now, I'm wandering how to wire these correctly.
Is this ok:

Wiring primaries to mains/fuse in series
Wiring secondaries in parallel, connecting
- to ac/dc 0V (one or two terminals)
+ to switch (both cables)
Switch to ac/dc ac1

Then for the led, acdc
+ to led
- to GRMP2 -in
Led to +in
0 to 0in
48V to 48V in

Then regulate voltage for reading after led (so +V would typical be +26V from acdc, if possible..)

Or are there better ways of doing this?
Or, no no?

Thanks!
Geir

G-Sun wrote:Hi!

I have a question regarding wiring of transformer, main switch, jlm acdc and power switch.

• I have a transformer like this
  http://www.selectronic.fr/transformateu ... ier-1.html
  Pri: 115V + 115V
  Sec: 24V + 24V
• a standard switch (like used for gobetween)
• an jlm acdc
• and a led, standard 2v drop

And it's for a dual GR MP-2 that takes +-24V and +48V


Now, I'm wandering how to wire these correctly.
Is this ok:

Wiring primaries to mains/fuse in series
Wiring secondaries in parallel, connecting
- to ac/dc 0V (one or two terminals)
+ to switch (both cables)
Switch to ac/dc ac1

Then for the led, acdc
+ to led
- to GRMP2 -in
Led to +in
0 to 0in
48V to 48V in

Then regulate voltage for reading after led (so +V would typical be +26V from acdc, if possible..)

Or are there better ways of doing this?
Or, no no?

Thanks!
Geir

HI Geir

Please send me a clear photo of the top of the actual transformer you have with the wires straightened out so I can read the top label clearly and draw on the photo to show you how to wire it for 230v and 48v centre tapped for the AC/DC kit. The power LED can just be wired across the +24vdc with a 4k7 series resistor or the +48v rail with a 10k series resistor.

Thanks a lot!

Here you are:

Thank you very much sir!
Very helpful

Hey Joe!

I'll the 48v rail on the powerstation die a horrible death if it is used to power unbalanced microphones?
Or is this only a problem if the unbalanced microphone grounds pin 3 on the xlr?

Sammas wrote:Hey Joe!

I'll the 48v rail on the powerstation die a horrible death if it is used to power unbalanced microphones?
Or is this only a problem if the unbalanced microphone grounds pin 3 on the xlr?

Since the 48v should only ever be wired to pin 2 and pin 3 of a input XLR via two 6k8 resistors the 48v rail will not care either way.

Hi, I'm looking to power 48V to 8 go betweens. And also powering ten dingos with gar2520 for balancing, unbalancing. Will the power station handle this ? What size power transformer ? 2 x 18V secondaries 25VA ? Or 50VA? I'm in Canada so 120V mains.

Thanks,
Dave