More noob questions - Axis Face

[John Squire]

I went to my local electronics store to get parts for my Axis Face, and as expected, ran into a few problems. Some parts were unavailable, and I had to make do with something else in a few places.

I'd like you guys to do me a favor and tell me what's ok and what's not.

15uF electrolytic cap - they said it doesn't exist, so I had to get a 22uF (I actually got two 22uF to wire in paralel to get something closer to 15uF, but maybe I should have gotten two 33uF?)

Resistors - I was supposed to get 1/4w resistors, but they only had 1/8 and 1w resistors, so I got the 1w, how bad a decision was that?

Now to the Millenium bypass part (forgot to mention I'm using it instead of the 3DPT switch):

I got 3 1N4148 diodes to do the high leakage low leakage  thing. You know, connect two of them in paralel and the other by itself.

Also, the MOSFET I got was the BS170.

I also got a 2N3904.

Ok, guys, now expose all my ignorance.

[petemoore]

  I went to my local electronics store to get parts for my Axis Face, and as expected, ran into a few problems. Some parts were unavailable, and I had to make do with something else in a few places.

I'd like you guys to do me a favor and tell me what's ok and what's not.

15uF electrolytic cap - they said it doesn't exist, so I had to get a 22uF (I actually got two 22uF to wire in paralel to get something closer to 15uF, but maybe I should have gotten two 33uF?)
  Just use a 22uf, IIRC that's what's shown in alot of FF schematics, what I/Many use...can tell difference? small...
  Resistors - I was supposed to get 1/4w resistors, but they only had 1/8 and 1w resistors, so I got the 1w, how bad a decision was that?
  They're just BIG, [will resist the same though], whether the leads fit through the holes...?...
Now to the Millenium bypass part (forgot to mention I'm using it instead of the 3DPT switch):
  Should work...see the Millenium article @ GEO for more info, IIRC you need 100k output impedance...
I got 3 1N4148 diodes to do the high leakage low leakage  thing. You know, connect two of them in paralel and the other by itself.
  I believe you're *referring to the reverse bias diode trick, using a Ge diode reversed across the B/E junction of a Ge transistor to prevent thermal runaway...but *I'm not sure.
  Also, the MOSFET I got was the BS170.
  I also got a 2N3904.
  Mosfet is mongo gain, 2n3904 is 'high gain for a FF. Especially Q1 is gain sensative, something around 80-150hfe for Q1, you can use anything but it may be high gain/squeal/oscillate, not clean up @ guitarvol. as well...
  *2n2369
  2n4401
  NTE123
  low gain 2n2222...there are others.
  For first FF...socket the transistors, use an R adjustment method in Q2 Collector bias resistor position, like a 20k trimpot?

[John Squire]

About the low leakage thing, I was referring to this thread: http://www.diystompboxes.com/smfforum/index.php?topic=980.0

I assumed it wouldn't hurt to have a couple of alternatives, so I got 3 1N4148 to use two in paralel for the high leakage diode and the other for low leakage. The 2N3904 I got as an alternative for low leakage (collector base). These are all for the Millenium 2, as well as the BS170.

The transistors I'll be using for the Axis Face itself are the PN2369A and the BD139. These were not too hard to find so I decided to get them, and put it all together first, and later experiment with different transistors.