LPB-1 into a Screaming Bird

[JebemMajke]

After looking at LPB-1 and Screaming Tree/Bird schematics I've noticed that the only differences are Two capacitors ( 0.1 for LPB and 0.002 for Bird ). So i thought it would be nice to make it switchable from LPB to treble booster but with one switch. After a while i've found a 12 pin 2 way switch. Can some one explain how can i wire caps on it?

[B Tremblay]

You can use a DPDT.  Use each half to short out a 1M resistor in series with the larger cap for the LPB mode.

[JebemMajke]

Thanks. I will try that, though i wish i could learn how to wire that 12 pin switch.

[Harry]

or you can use a pot to blend between the two

[EATyourGuitar]

I'm looking at the schematics and the screaming bird uses a 5133. I do see what your talking about though. if I keep the 2n5088 and the two resistors that go with it, then yeah I could do the screaming bird switch. looking at the mole, it also similar but the 2 more caps would require a 7 pole switch.

[jk-fm]

You could make a high pass filter with a second cap and a pot to ground before the existing LPB cap, 0.1u and 100k reverse log would be a good range.

[Mark Hammer]

I'm looking at the schematics and the screaming bird uses a 5133. I do see what your talking about though. if I keep the 2n5088 and the two resistors that go with it, then yeah I could do the screaming bird switch. looking at the mole, it also similar but the 2 more caps would require a 7 pole switch.

Nothing particularly special about the 2N5133 for booster purposes.  It was simply EHX's favourite NPN transistor at that time and used in just about everything they made, regardless of functon.  Consider it the 2N5088 of the era.

[EATyourGuitar]

I bought 50 fs3699 from smallbear and they were all 5133 with gain in the 100 - 200 range maybe one 250hfe in the lot.