Electronics Gurus UNITE - Power Supply isolation circuit

GIJoe

Bit of a long post...here we go:

So I currently have a t-rex fuel tank classic power supply, which is great. However, I have since sold my 12V delay and AC pedals, so negated the need for those ports, and bought a strymon timeline, which does not like the other ports, as they are daisy chained.

I also own a Line 6 M9 so with the strymon joining the ranks I now have 3 power supplies to plug in!

With this in mind I purchased a diago powerstation from the classifieds with a few adaptors and a gigrig distributer.

Here's the question:

I would like to isolate the digital pedals (I plan to run the m9 on dc too, as it has a bridge rectifier internally.) but the stock diago isolator can only handle 100ma.  The gigrig isolators seem to be able to take more, but they are £60!

So...what do I need to make my own?  An opto-isolator?

Surely this is a simply little circuit - nobody tried before?

Misterg

I can't follow what you're trying to do, but I do know that a DC-DC isolator is not an easy thing to build. You can get switching converters that will do it, but you risk noise, especially if there's more than one, or if they're combined with a switching (digital??) supply. I know, I've tried :-/

(Unless I'm missing a trick, that is...)

dindude

Pm'd you Joe

dano

If i follow it properly youplan to run the M9 from the 12V DC output of the Trex and a Strymi from the power station ? I dont quite get why pedals you want to run from the same supply and thus isolate.... and yez i am a power electronics man so maybe able to help out!

GIJoe

dano said:

If i follow it properly youplan to run the M9 from the 12V DC output of the Trex and a Strymi from the power station ? I dont quite get why pedals you want to run from the same supply and thus isolate.... and yez i am a power electronics man so maybe able to help out!

Yeah sorry perhaps I was a bit unclear.

I want to run all of them from the Diago.

• The voltages are all ok (all 9v).
  
• It has enough current.
  
• I am going to try run the m9 off the diago - I have read it has a bridge rectifier, so dc instead of ac in should be ok, worst case it does not work.
  
• The strymon whined a lot on the 9v outputs of the t rex, as they are pretty much internally daisy chained.

Basicially is there a cheap 'diy' alternative to the pricy gigrig isolators?

dano

There are loads of circuits about but doing it properly is a skill. you need a proper 'box' with either a transformer or isolated dc:dc converter. depends if you are any good at soldering and building ? you could get an isolated dc:dc converter from farnell, an enclosure two sockets and a few caps and make one ?

GIJoe

dano said:

There are loads of circuits about but doing it properly is a skill. you need a proper 'box' with either a transformer or isolated dc:dc converter. depends if you are any good at soldering and building ? you could get an isolated dc:dc converter from farnell, an enclosure two sockets and a few caps and make one ?

Well I can use a soldering iron

I might just plug it in a see how much noise we get...

Also might be easier just to isolate everything else using the diago adaptors!

crunchman

There doesn't seem to be an easy way to power Strymon, Line 6 etc without spending a fortune or using multiple supplies. Even if you buy a supply with isolated outs most of them won't have 300mA capability for the Strymon, and the 12V AC for the Line 6.

GIJoe

UPDATE - I emailed Diago and got a great reply!

They are going to send me a diagram on how to isolate the strymon using their existing isolator, and they have a prototype of a 400mA isolator which will be on sale in a couple of months!

dano

GIJoe said:

UPDATE - I emailed Diago and got a great reply!

They are going to send me a diagram on how to isolate the strymon using their existing isolator, and they have a prototype of a 400mA isolator which will be on sale in a couple of months!

That sounds like a good option. I had a quick look just now and a suitable isolated dc:dc converter is about 20 squids, plus another tenner for the enclosure plus other bits you need, couple of hours to make it and £60 on a 'proper' Diago or gigrig is quickly becoming a good price.

shuikit

@gijoe could you share what diago emailed you? In curious..

GIJoe

shuikit said:

@gijoe could you share what diago emailed you? In curious..

Yeah, They said they would send me a diagram of how to use the low current isolator for multiple pedals - I'm still waiting for this.

I assume I would power overdrives etc with the isolator, leaving what is left for my timeline, isolated from everything else.

They also said they have a prototype 400mA isolator that should be released in a couple of months.

shuikit

Yea, I think I might have to wait for that as I'm getting a little bit of noise from my Line6 m5.  Funnily I've only recently noticed it and more so at home.  

Likewise, my guess would be to daisy chain the other pedals off one of the 100ma isolators but that's not going to be enough for my other pedals (I don't think).