Powering go between & FET DI

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LetterBeacon
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Joined: Tue Apr 26, 2011 10:46 pm

Powering go between & FET DI

Post by LetterBeacon »

I'm planning on building a REDD 47 point to point, but I also want to add a JLM go between kit as well as a FET DI. I'm a bit stuck when it comes to supplying power to the the JLM PCBs.

At the moment I'm thinking of adding another transformer into the case and using a JLM AC/DC kit to power the go between and DI kit, but it does seem a bit inelegant to do it this way, and perhaps a bit overkill. Is there another way to do it maybe incoporating the transformer that I'll be using for the REDD?

I'm going to be using a Hammond 370bx power transformer to power the REDD 47, it has the following secondary windings: 550V CT @ 58ma, 5V CT @ 2A, 6.3V CT @ 2A.

Any help will be much appreciated!

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Joe Malone
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Re: Powering go between & FET DI

Post by Joe Malone »

LetterBeacon wrote:I'm planning on building a REDD 47 point to point, but I also want to add a JLM go between kit as well as a FET DI. I'm a bit stuck when it comes to supplying power to the the JLM PCBs.

At the moment I'm thinking of adding another transformer into the case and using a JLM AC/DC kit to power the go between and DI kit, but it does seem a bit inelegant to do it this way, and perhaps a bit overkill. Is there another way to do it maybe incoporating the transformer that I'll be using for the REDD?

I'm going to be using a Hammond 370bx power transformer to power the REDD 47, it has the following secondary windings: 550V CT @ 58ma, 5V CT @ 2A, 6.3V CT @ 2A.

Any help will be much appreciated!
Use our 48v 315mA internal SMPS

or

Small transformer and AC/DC kit

or

If you want to use the 370bx power transformer wire the 6v3 winding with its centre tap to 0v join the 5v winding which is not normally used on to one end of the 6v3 winding to make 8.15vac rms (11.5vac peak). (You must make sure the 6v3 and 5v windings are in phase) And make a pump charge circuit with 6 x 1N4007 diodes and 5 x 470uF 50v caps to make about 55 to 60vdc unreg and use our TREX kit with 47v zener to make stable 48v rail for Go Between and Fet DI and phantom power. See below picture. C6 is actually already on the TREX kit.

Image
Joe :-)
JLM Audio
Capturing Audio without Injury

LetterBeacon
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Joined: Tue Apr 26, 2011 10:46 pm

Re: Powering go between & FET DI

Post by LetterBeacon »

Brilliant - thanks for the info!

One more question: What type of switches are used on the Go Between? I want to use slightly bigger ones and space them out a bit, and use wires to connect them to the PCB.

Thanks!

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Joe Malone
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Re: Powering go between & FET DI

Post by Joe Malone »

LetterBeacon wrote:Brilliant - thanks for the info!

One more question: What type of switches are used on the Go Between? I want to use slightly bigger ones and space them out a bit, and use wires to connect them to the PCB.

Thanks!
GO between kit uses DPDT switches.
Joe :-)
JLM Audio
Capturing Audio without Injury

LetterBeacon
Posts: 7
Joined: Tue Apr 26, 2011 10:46 pm

Re: Powering go between & FET DI

Post by LetterBeacon »

Hi Joe -another quick question:

Because I'm going for a vintage look on my REDD 47 build, I would prefer to use lamps instead of LEDs on the front panel to indicate phantom power. I'm going to power it using the 6.3vac tap on the Hammond PT.

My first thought was to use a 3pdt toggle switch for the phantom power switch, using the first two poles for the go between PCB, and the third pole to switch the lamp on. However I can't seem to find any 3pdt toggle switches thy are the physical size I'd like. They're all 'miniature'

Is there another way to switch the lamp on when the phantom power is switched on that you can think of? I'm a bit stumped!

Thanks a lot!

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Joe Malone
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Re: Powering go between & FET DI

Post by Joe Malone »

LetterBeacon wrote:Hi Joe -another quick question:

Because I'm going for a vintage look on my REDD 47 build, I would prefer to use lamps instead of LEDs on the front panel to indicate phantom power. I'm going to power it using the 6.3vac tap on the Hammond PT.

My first thought was to use a 3pdt toggle switch for the phantom power switch, using the first two poles for the go between PCB, and the third pole to switch the lamp on. However I can't seem to find any 3pdt toggle switches thy are the physical size I'd like. They're all 'miniature'

Is there another way to switch the lamp on when the phantom power is switched on that you can think of? I'm a bit stumped!

Thanks a lot!
Only one side of the 48v switch switches the phantom between 0v and 48v so the three terminals closest to the edge of the PCB can not connected to the PCB and used to switch a normal lamp. So a Normal DPDT switch will work fine.
Joe :-)
JLM Audio
Capturing Audio without Injury

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