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Collaborate?
http://www.diystompboxes.com/smfforum/index.php?topic=86933.0

If I could do an amp design, I'd do stereo IN and stereo OUT.  Then again, if this is tiny enough, you could just build 2 amps.

By "tie high" I mean that pin should be connected with a wire to the positive supply used on the Vcc pin.  It's a short version of saying "logic high" meaning a logical high value.  Logic low, by contrast would be ground, zero volts, or whatever supply you happened to use as Vss on the chip.

I do a lot of armchair analysis of things from a digital point of view (I say to myself "when the input goes high, the output goes low...") which gives me a very quick and dirty idea of what's going on.  It doesn't work all the time but for a surprising number of things it is quite useful.

You had me at LED. 

Friday again!  This week its even better!!
 

Thanks, I'll try that. I did post a topic there about cloning this pedal. He hasn't chimed in on his own yet. I especially think it would be cool to make a replica of the first Ross "script" version. If they did what they did with their script version of the Ross Distortion, then it most likey shoud be an exact clone of the 76' MXR Dyna Comp script pedal PCB layout and all. I do have pretty good photos of the MXR script PCB front and back. I'd like to know if the Ross script is identical to the MXR script so then I could model my clone from the MXR board shots and maybe it would be just as accurate to call it the Ross Compressor script version that came in a narrow Bud box just like MXR used:

So about 2 months ago the front Differential in my awesome, beastly 1999 Ford "Explosion" V8 AWD Explorer.

After many weeks of carpooling, bumming rides and borrowing cars, I finally got my finances in order and started trying to find a new car.  Yesterday I lucked out an found a 2008 Ford Focus SES completely with Spoiler and interior LED mood lighting.  It automatically goes faster than cars without it!  It had been on the lot all summer and they just marked it down again putting in within my budget.  38k miles and oh so shiny!

I fell very certain that Mr. analogguru over at FreeStompBoxes has the original schematic (without mods). If you ask him nicely, and explain what you are aiming to do, he'd probably send you a copy.

First was to find out if one gate of an XOR can be used as a linear amplifier.  Turns out that it can! 

Cool! So maybe we could use two gates as gain stages and the other two for octave. I love using up an entire IC like that.

For a 4070, tie one pin high and use the other as an inverting input

What do you mean by "tie high"??


It also occurred to me just now that I could probably use a Bazz Fuss as the dirt portion of this circuit. I think I'll try that.

I've had some 4070 and 4077 chips for several months, but finally put them on the breadboard for the first time a couple nights ago.  I plan on working on a similar XOR-doubler circuit, but I'll be doing some more general XOR-related experiments as I go.

First was to find out if one gate of an XOR can be used as a linear amplifier.  Turns out that it can!  For a 4070, tie one pin high and use the other as an inverting input; feedback bias like you would a 4049/4069 amplifier.  Note that clipping is not soft like the typical 4049-based distortion.  The internal circuitry of an XOR/XNOR is quite different so this is not a big surprise to me.

For a 4077, that first pin would be tied low instead.


I'm not sure yet if one gate has enough gain before clipping to be used as a replacement for the BJT input stage in Escobedo's circuit, but so far the results are promising.

I'm researching the classic gray Ross Compressor sustainer pedal to make a clone from. All I see are people's modified schematics and layouts so not sure what is original and what is changed for improvement. But I'm not looking for any improvements even if they are better. This is so I can make a clone again of a 'vintage original' if you can appreciate what I want to end up with. I wouldn't mind cloning a vintage 76' MXR Dyna Comp as an alternative, but feel weird legally cloning a pedal that is in current production as is the MXR custom shop's 76' vintage re-issue.

I've been starting to collect pictures of the actual Ross Compressor's PCB in another attempt to reverse engineer a new 'spec' layout as I successfully did with my gray 250 clone. But one thing I cannot find yet are pictures of the Ross Compressor trace side of the PCB so I can see where parts connect point to point with each other. Does anyone have pics of the trace side? Finding pictorial detail info on this pedal is much more elusive than I expected. If you have any (original gray model if possible) Ross Compressor pictures of the circuit board from both sides please post them in reply to this topic, thanks.

My only fallback is to compare user "modified" schematics of the Ross Compressor with the similar '76 MXR Dyna Comp, since I do have pictures of the component and trace sides of that earlier pedal to reverse engineer a new layout from. This is last resort since I'd probably end up with a hybrid and want a pure Ross to base a clone from in this case.

Here are some schematic reference links. These examples all differ so which one is most accurate to the original and were there any differences (http://www.effectsdatabase.com/model/ross/first/compressor) between the 'narrow' box version and the R-30 version? Also, why do some schematics say the Sustain pot is 500K linear or 500K reverse log, and why do some say the Output pot is 100K or 50K? What kind of pots were in the original anyway?

General Guitar Gadgets - J.D. Sleep schematic:
http://www.generalguitargadgets.com/pdf/ggg_dnr_ross_sc.pdf

Fuzz Central:
http://fuzzcentral.ssguitar.com/ross.php

Geofex - R.G. Keen schematic:
http://www.geofex.com/PCB_layouts/Layouts/d&rpub.pdf

Tonepad (I have the PDF but not sure this is the link since my Vista PC gives an error) Comparous schematic:
http://www.tonepad.com/getFileInfo.asp?id=9