Question: -5V DIY circuit for supergun

Vendest

Krauser's Shoe Shiner
Joined
Jun 23, 2016
Posts
240
Hi,

I've bought off ebay a cheap psu with +5 +12 -5V supposedly available at the terminal.
-5V rail is actually blanked off and there is no extra tapping point on the coil/winding.

Could someone indicate how to build a circuit that can draw -5V out of available positive voltage?
Not sure how much current does KI or MK pcb require but it should 1/2 amp to 1amp at most I guess.

Thanks
 

Vendest

Krauser's Shoe Shiner
Joined
Jun 23, 2016
Posts
240
That's exactly what I am looking for but the $50 for int' shipping is a no go.
 

Vendest

Krauser's Shoe Shiner
Joined
Jun 23, 2016
Posts
240
Use a Negatron.

https://www.dimensionengineering.com/products/negatron

If you need me to ship you one let me know. I'm about to order some so it would be about $26 shipped to you.

I would look into the Negatron. They have been pretty popular option in cabs or superguns that didn't have the -5v rail.

https://www.dimensionengineering.com/products/negatron

They appear to have pretty inexpensive international shipping.



edit: damn, James beat me to it.

Thanks for the tip, 500mA should be enough for KI or MK.

@James, Ok I'll send you the payment via PayPal shortly. Thanks
 

donluca

Ninja Combat Warrior
Joined
Aug 19, 2015
Posts
529
Get a 9V battery, swap the leads and put a voltage divider to get it down to -5V! :D

On a more serious note, if you're looking for a 100% DIY cheap solution, this might fill the bill:

http://www.aaroncake.net/circuits/vinvertr.asp

it's an extremely simple circuit, you can do better with other components (opamps and such), but it's gonna need more components (ie: added costs).

EDIT: ok, just saw you went for another solution. Oh well, I'll leave this here for other ppl :P
 

Vendest

Krauser's Shoe Shiner
Joined
Jun 23, 2016
Posts
240
Get a 9V battery, swap the leads and put a voltage divider to get it down to -5V! :D

On a more serious note, if you're looking for a 100% DIY cheap solution, this might fill the bill:

http://www.aaroncake.net/circuits/vinvertr.asp

it's an extremely simple circuit, you can do better with other components (opamps and such), but it's gonna need more components (ie: added costs).

EDIT: ok, just saw you went for another solution. Oh well, I'll leave this here for other ppl :P

That's really cool! thanks for sharing
 

Xian Xi

JammaNationX,
15 Year Member
Joined
Dec 1, 2005
Posts
27,748
Get a 9V battery, swap the leads and put a voltage divider to get it down to -5V! :D

On a more serious note, if you're looking for a 100% DIY cheap solution, this might fill the bill:

http://www.aaroncake.net/circuits/vinvertr.asp

it's an extremely simple circuit, you can do better with other components (opamps and such), but it's gonna need more components (ie: added costs).

EDIT: ok, just saw you went for another solution. Oh well, I'll leave this here for other ppl :P

Nice but 280mA isn't much. Plus he would need a regulated 6v supply to get a regulated -5v output.
 

donluca

Ninja Combat Warrior
Joined
Aug 19, 2015
Posts
529
Nice but 280mA isn't much. Plus he would need a regulated 6v supply to get a regulated -5v output.

He can just use the +12V and use a voltage divider (two resistors) to get it down to 6V.

I'm not sure how much current boards draw from the -5V but my guess is something very very low, not exceeding 100mA.
 
Top