Proco Turbo Rat, anybody got one ?

[Rectangular]

Hey all, I was curious if anyone had a proco Turbo Rat they'd be willing to open up and take some pictures of ?  I've been wanting to build one of these forever, but the handful of schematics posted around the net (which I already have) are all inconsistent, and from what I've heard, not very impressive sound-wise. it doesn't seem to just be a Rodent with some red led's and a 308 capacitor swap, I'd personally like to make a verified pcb layout once and for all. any takers ?

[zarathustra]

As far as I know, the only difference between a stock Rat and a Turbo Rat is the clipping diodes. Stock Rats use Si diodes, Turbo Rats use LEDs.

[ambulancevoice]

yeah, ive read that to
quote from Dano at beavis audio of the FKR page
"LED: 2x red LEDs for much more intense clipping (incidentally, this is the difference between the Rat and the Turbo Rat)"

[Rectangular]

yes I've read that as well, but I don't think that's the case. thats why I'm hoping someone can open their turbo rat and verify this. if its just a redent with two led's, then I'll eat my hat. I don't believe proco would release an entirely new product based solely around a clipping diode swap.

[George Giblet]

This page describes rat differences:
http://www.happybob.com/rstrand/rat/rat_versions.htm

If you search through the archives dosmunn?  posted a link to a site which has pictures of the insides of all the rats.  It was put up within the last year.

[Rectangular]

yeah I know the website,  the image links have been dead forever, and I have all the schematics from there (including the portuguese one) . thats why I'm looking for some new pictures

giblet:  Im familiar with the dosmun site,  unfortunately the pictures leave something to be desired. see for yourself:

http://webpages.charter.net/daosmun/Turbo%20Rat.htm

[jonathan perez]

yes I've read that as well, but I don't think that's the case. thats why I'm hoping someone can open their turbo rat and verify this. if its just a redent with two led's, then I'll eat my hat. I don't believe proco would release an entirely new product based solely around a clipping diode swap.

1. dont be so skeptical. try different diodes in your rat, if you have one, and have a listen to the difference.
2. it IS the case when youve got more than a handful of people verifying it on the ever shrinking internets.

check for other value differences in the schematics; resistors, capacitors, and any other changes that would make a sonic difference.

[George Giblet]

> unfortunately the pictures leave something to be desired

I thought the site provides a good overview from a purchaser perspective.  As far as a technical perspectve goes, yes,  you can't work much out at all (despite the pics of the internals).

Anyone know the circuit (or the type of clipper diodes) in the bass Juggernaut?

[Rectangular]

hey midway,  I'm sure red LED-ing a Rodent or Rat would definitely put it in the ballpark for what a turbo rat sounds like,   I was just hoping someone here might actually have had one on hand, to verify what else might be different. it would save me the trouble of finding  a used one in real life,  buying it,  jotting down the innards, and re-selling it.

I guess proco never released service manuals  ? all the schems seem to be reversed engineered, most based off R.G's from 1998

[oldrocker]

Well I built the Rat from R.G.'s schem and at first I just used the SI diodes.  Then I decided to add two yellow LED's with a DPDT switch so I could switch between the two.   I don't have my Turbo anymore (gave to an old band member) but it sounds just like the one I had as far as I can remember.  Sometimes I use the Turbo switch to boost my guitar into a cleaner loud lead option.  Sorry I couldn't be more help.  Do what I did, build it mod it and try it.  You may like it or you may not but it would be great project none the less.  No?

[dosmun]

If you are looking at RG Keens schematic the differences in the Turbo are:

LED's for clipping diodes
R1 - 2.2M
R3 - 2.2M
2.2M pulldown resistor at the input

[dosmun]

Here is a better pic.  Sorry about the battery clip being in the way.
http://i183.photobucket.com/albums/x154/dosmun/Turboinside.jpg

[oldrocker]

Correction the Rat I built was from Tonepad.  Just added the yelllow LEDs.  Sounds nice.

[Rectangular]

hey dosman, that's awesome ! thanks so much

its amazing what a difference a little magnification can make

I'll try breadboarding one tonight and seeing how it sounds. its frustrating how all of these rat schematics vary from each other, especially for the turbo rat. they can't all be correct