My First Schematic

Started by M.Spencer, February 22, 2015, 08:24:49 PM

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LightSoundGeometry

#20
one quick question, I believe the bc108 are silicon tranies so i wont be able to put my pnp germanium ones in and give them a listen?

like a fool, I bought sets of germaniums thinking I could do a fuzz lol. (you guys would get a chuckle if I showed the picture of the fuzz kit I I bought and tried putting together )

also, can you substitute a pnp or a npn for a jfet ?

M.Spencer

#21
Quote from: LightSoundGeometry on March 19, 2015, 06:56:04 PM
one quick question, I believe the bc108 are silicon tranies so i wont be able to put my pnp germanium ones in and give them a listen?

BC108s are NPN, so you can't sub a PNP (germanium or otherwise) without first modifying the circuit. And from what I understand silicon transistors are more stable than germanium, so to swap a Si for a Ge you'd need to change the biasing resistors or trimpot values somehow (I'm not exactly sure how to calculate that).
You can't directly substitute a BJT for a JFET.
And if I'm incorrect on any of this will someone please please correct me.  

Quote
like a fool, I bought sets of germaniums thinking I could do a fuzz lol. (you guys would get a chuckle if I showed the picture of the fuzz kit I I bought and tried putting together )

I'd never laugh at another beginner; this stuff isn't rocket science but it's not a cakewalk either. Keep those germanium PNPs, you will likely find use for them on a future build!

M.Spencer

Quote from: antonis on March 18, 2015, 09:22:24 AM
Quote from: M.Spencer on March 17, 2015, 06:41:34 PM
But I'm not sure what you mean by E24 values. Could you explain?
Ε6, Ε12, Ε24, Ε48 & Ε96 are preferred value system with number indicating how many standard values are included per decade..
(this has to do with value tolerance..)
http://www.logwell.com/tech/components/resistor_values.html


Thank you! As a hobbyist with a big 'ol resistor kit I'm less worried about keeping my circuits within E12 values. If I were to manufacture multiple units I imagine my stance would change. But thank you for the knowledge!

LightSoundGeometry

I kind of already did ..my first successful real build was that octavio, I had seen one named the tim escabedo pushme pullyou and it had a germanium tran in it ..when I place by BOM for the fuzz ( I am going to try the DAM one first) I will also place an order for teh escebedo version..actually I need to go download those and get a list together !

thanks spencer - all you guys here are fantastic with the advice and help