Tube Sound Fuzz, Calavera, & inside the Red Llama.

[bobbletrox]

PART ONE:
I've become infatuated with CMOS Hex Inverters, and have been looking to see how different pedals use them and crud like that.  Craig Anderson's Tube Sound Fuzz looks interesting and I hear the Red Llama is based on it...and from this picture, it looks the same:



I'm guessing the Tant is the output cap?  The empty spots on the board look like they're for the Foot Pig or somethin'.  I wonder how the ceramic input cap and Tant output cap effect the tone?  

PART TWO:
I've also been lookin' at Tim's Calavera since his PWM sounds so great!  Although, before I go on my merry way for a while, I've gotta ask: are the trimpots for setting the bias?  If so, how will I know when it's right?  Sorry if that's a bad question!

Thus concludes the Odyssey.

[RDV]

WOW! That's a Llama with one of those stupid cheesehead thingys on it's melon! How quaint!

RDV

[cd]

The RL is exactly the same as the TSF, just double the size of the largest electrolytic and you're done.

[petemoore]

But since you mention it, my brothers leg was ravaged by polio at age five, growing to about 40% of its expected weight.
 The doctors cut and inverted a section of his good leg, to stop growth, and it did, the procedure was done too early in his growth pattern, and as a result his strong leg grew to be longer than the very weak one by about 2.5 inches.
 I know most often People don't associate that it hurts to hear terminolgy used to indicate a  tragic handicap as a way of describing their frustration or pain, words bounce funny like a football, and mean different things to different people.
 If you'd been hurt real bad repeatedly by intentionally demeaning name calling, you would quite probably have a reaction when these terms that describe your tragic condition are used to refer to 'bads'.
 He lived vicariously, with a pain so deep it got hard to tell the cause.
 He self destructed last year. He was really a great guy, always thinking of others. The term "lame' can bring heavy mental pain to those programmed by peers and society to feel it.
 I used the term in front of him once by accident or fruedian slip. I kick myself whenever I think of it.
 I'm sorry to choose your post as a soap box for political correctness, I really don't think you intended any harm. Just one of those things I guess...

[gez]

are the trimpots for setting the bias?  If so, how will I know when it's right?

Yes, they bias the inverters.  There should be a post in the archives where Tim explains how to set it up.

I've messed around with trimpot bias in the past.  I just measured the output of the inverters with a meter and adjusted the trims til I got the outputs to nestle at half the supply (trimpots should be roughly in the middle).  From there you can tweak it by ear.  You'll know 'when it's right' cos it'll sound right!  

[Jason M.]

The Red Llama is almost exactly the same as the TSF, with minor component value changes:

The input cap is changed from 0.1uF to 0.05uF metal film to reduce bass response.

The coupling cap between inverters is changed from 0.05uF to 0.033uF metal film. Less bass, again.

The +9V goes through a 1k (instead of 100 ohm) resistor, is decoupled by a 330uF (instead of 100uF) electrolytic cap, and has a 1N4001 protection diode. Better filtering and protection.

The small ceramic caps across the inverters are changed from 10 pF to 100 pF. Reduced noise.

Leave out the lead/rhythm switch and you have a Red Llama.

The lower coupling caps really help limit the bass, which is welcome, as my TSF is too woolly.

As for the unpopulated portion of the board: I don't think it is a Camel Toe, because the Camel Toe was two different pedals in one case. The Red Llama and the Green Rhino, I think.

This board seems like it was used for two different pedals. Populated like this it is a Red Llama. Fully populated, it becomes something else.
I'm thinking it is a Purple Platypus because there are not enough offboard connections for it to be a Camel Toe.

I bought the Red Llama specifically to trace it out. I have traced the board and it seems like it is a TSF driving a circuit that slightly resembles the Green Ringer. There is one offboard trace that I can’t figure out where it goes to and I have not seen the inside of a Purple Platypus to confirm my suspicions.
I plan on doing a full schem and layout once I can get a look at the inside of a Platypus.

[george]

hmm the rest of the board looks really RE friendly ... I mean it's TELLING you it's got (by the look of the outlines) metal can PNP and NPN transistors, 2 diodes.  It even tells you resistor and cap types and values ...

all I need to do now is find a schematic with an NPN and PNP and 2 diodes ...

[bobbletrox]

But since you mention it...

I edited the sentence for you pete.

Yes, they bias the inverters.

Thanks for the tips gez!  I'll give that a go.  The Calavera is a great lookin' circuit.

Hey, that's my pic of the inside of my Red Llama that I have for sale.

Yikes!  Thanks for the component values Jason!  I thought the ceramics must have been the input and coupling caps because of their location on the board, so thanks for clearing that up too.  You're very generous by sharing that information considering you bought the Red Llama specifically to trace it out.  I hope I can return the favour someday.

[jrc4558]

It seems to me that the other half can accomodate a Jordan Bosstone. Am I right?

[rhinson]

hello there,  so the remaining resistors on the board are the same as the tsf (ie---100k, 100k, and 1meg), is that right?  also are the pots the same values (1meg drive and 10k vol),  and looks like there is a resistor on the vol pot to ground--i guess so you can't turn the vol. all the way down.  what value is that resistor ---470 ohm?    rh

[Jason M.]

hello there,  so the remaining resistors on the board are the same as the tsf (ie---100k, 100k, and 1meg), is that right?  also are the pots the same values (1meg drive and 10k vol),  and looks like there is a resistor on the vol pot to ground--i guess so you can't turn the vol. all the way down.  what value is that resistor ---470 ohm?    rh

Yes, the resistors and pots are the same value of the TSF, except for the resistor in the power supply filter. It is changed from 100ohm to 1k.

There is a 1M resistor on the output, from the wiper to ground.

[bobbletrox]

Is it ok if I post a schematic I drew up for the Red Llama?

[jrc4558]

I'm no lawyer, but I would imagine that you could. Common sence; Huge used someone else's design (Craig Anderton in this case), and Craig has made his design public in a book that he wrote.
You cannot post the PCB artwork though! That is for shure the intellectual property of the one who designed it. On the other hand, the PCB required can easily qualify for a first test in the PCB101 introductiory course.

[bobbletrox]

On second thought, I won't post it after all...

...and I hope folks will use Jason's information for personal use only!

[Arno van der Heijden]

On second thought, I won't post it after all...

Mr. Huge has stated several times here that he doesn't have any problems with people posting his schematics. The artwork is a different story...

[gez]

I'm still waiting for a shematic of the Dalai...

[rhinson]

hello there,  since the switch is left out that was in the tsf version of this circuit,  which value of resistor (100k or 10meg) does the red llama use in the 1st feedback loop with the drive pot?   thanks very much.    rh

[MarkB]

Sorry to hear about that Pete... but before you get too offended by the 'misuse' of the word, do understand that it's not a misuse at all...

according to websters (#3 would the common use of 'lame' for something like what was posted earlier)

lame1    ( P )  Pronunciation Key  (lm)
adj. lam·er, lam·est

  1. Disabled so that movement, especially walking, is difficult or impossible: Lame from the accident, he walked with a cane. A lame wing kept the bird from flying.
  2. Marked by pain or rigidness: a lame back.
  3. Weak and ineffectual; unsatisfactory: a lame attempt to apologize; lame excuses for not arriving on time.

Doesn't make it right if people used it for name-calling, etc.. but it is a real word with a real meaning other than for phsyical ailments.
"-)

[Jason M.]

hello there,  since the switch is left out that was in the tsf version of this circuit,  which value of resistor (100k or 10meg) does the red llama use in the 1st feedback loop with the drive pot?   thanks very much.    rh

100k in series with the 1M drive pot.