Tone Bender MKII part question

[newperson]

Hi,
I just built one of these from tonepad's layout.  It works.  The fuzziest fuzz I have ever played with.  I got the transistors from Small Bear and he sent along a sheet with the resistor values.  All of them matched Tonepad's layout except R7 which Small Bear said 1K while the Tonepad layout said 2.2M.  I put in the 1K.  What change would it make with this resistor change? 

Also, every back post I read talks about biasing the unit to 4.5 volts.  What resistor is replaced with a pot to bias the unit?  Is the R7 the one for biasing the effect and the transistor values that Small Bear sent match with a 1K resistor instead of a 2.2M?

thanks,
paul.

[petemoore]

Hi,
I just built one of these from tonepad's layout.  It works.  The fuzziest fuzz I have ever played with.  I got the transistors from Small Bear and he sent along a sheet with the resistor values.  All of them matched Tonepad's layout except R7 which Small Bear said 1K while the Tonepad layout said 2.2M.  I put in the 1K.  What change would it make with this resistor change? 
  Heres the schemtiac 
  http://www.tonepad.com/getFile.asp?id=86
  It shows R7 before input cap, as a *pulldown resistor* for pop-free TBypass switching, anything from 1m to somewhat bigger'll be fine, or none, if you have 1k from signal path to ground at input you're seriously reducing the signal voltage at that point.
  Also, every back post I read talks about biasing the unit to 4.5 volts.  What resistor is replaced with a pot to bias the unit? 
  You can make R6 a 10k or 20k pot, and easily 'dial in' resistances to bias Q3 collector to get 4.5v in a TBMkII cct.
  Is the *R7* the one for biasing the effect and the transistor values that Small Bear sent match with a 1K resistor instead of a 2.2M?
  I'm not sure we follow the 1k/2m2...gotta be a mixup somewhere along the line, R7 can be eliminated, or just made 'big' for eliminating poppy bypass switching without dragging the signal down near ground. 1k to ground there...not much'll get past that.
thanks,
paul.

[newperson]

so the 1K is bad for me and I should switch it back to the 2.2M? 
thanks for explaining the biasing resistor also.
Also, if I want more bass/less treb out of the effect should I switch the two 4.7mfd caps to something like 10 mfd caps?  or is that too much of a jump?
paul.

[newperson]

Do you have to cut the leads of GE transistors?  The ones that Small Bear sent have very long leads on them.  Should they be cut?  I have them in sockets.  If they are not cut should they be wrapped with something so they will not pick up noise?  I have not boxed the pedal yet so I cannot really tell how much of the noise will be going away.  Right now it is noisey.

Paul.

[newperson]

yet another question,

when I touch the top of the 2nd transistor it causes the pedal to pickup sounds.  1 and 2 do not do this.  should this happen?

[Rick]

Sure you can cut the leads of the GE xstrs shorter, they're way too long on most types. I've cut nearly 200 of them with no failures so far. Just be sure when soldering not to heat them much past 8-10 secs for insurance. They may take a little more than that but why chance it. I use a little round heat sink that pushes onto the transistor body for extra insurance when soldering them. Haven't fried one yet.

Also the above tips on biasing the bender should be done, 'cause you will be a happy camper when you dial in the sweet bias spot for you circuit and the thing does it's magic. I use a 10 or 20k trimpot soldered in place of the standard resistor for the q3 collector and adjust to around 4.5 to 5.5 volts, but by all means play your guitar though it while doing this and pick your favorite spot. This is the fun part  - tune your beast!

If your circuit is very noisy after doing this, you may have a flaky GE or more. I had one circuit that sounded like heavy rainfall in the background. It turned out to be a really leaky GE (1500 microamps). I test them all now with RGs leakage tester before use. Good luck with it ...Rick

[petemoore]

so the 1K is bad for me and I should switch it back to the 2.2M
  1k at input to ground, or anywhere in signal path for that matter will let very little past. 1m or higher for a pulldown resistor is generally the rule, 2m2 is just fine.

[newperson]

OK,
thanks for the input.  i will switch the resistor and add the pot to bias the pedal.  this will give me something to play with tomorrow.

paul.