So, what would you build?

[pi22seven]

I got a couple of 2n527 and a couple 2n404a from work the other day for free.

Not knowing leakage or gains, what do you guys suggest I build with them?

[tcobretti]

Well, the classic Ge circuits that come to mind are the Ge Fuzz Face, the Rangemaster, and Pete Moore's Rangepig.  I haven't built the Pig, but supposedly it works well with questionable Ge transistors.

If you search the archives, you can find all the necessary schems/layouts.

[zjokka]

I think the gain and leakage will be more important than the type of transistors. I have a lot of 50 2N404a's around that I just don't use, but measured all their gains and could make only a few fuzz faces out of them, because most of these 2N404as will measure around hfe 130. Don't know about the other Ge's you mentioned

But T, isn't the RangePig a piggyback version of the Rangemaster, ie with parallel SI transistors?

zj

[tcobretti]

As I recall, the Rangepig is a darlington using a Ge and a Si (both PNP).  It allows the Si to boost the volume of low gain Ge transistors.

I don't know why I haven't built one; it's a great idea.

EDIT: here's the schem
http://img.photobucket.com/albums/v207/petemoore/RangePIG.jpg

[petemoore]

  I'd build a FF with 8 pin socket for transistor swapping, Q2CR as trimpot, large input cap can easily be seriesed to smaller value with 2nd input cap, same for output cap, put something about right or at least DC blocking, then mess with the values by adding offboard caps to the Input/output wires, or just socket those too.
  The feedback resistor [100k] could be made as 150k, then reduced in value easily if you leave room [I do it above board cause I left some lead length above board on the resistor to fascilitate clipping a 250k pot or piggybacking' a parallel resistor to].
 Makes a good testboard, to test by ear with.
 I'd use SB's 1k FF pot >and add about 820ohm stop resistor to ground.
 Then you can diddle with rebiasing different transistors all day, see what this one sounds like, get a higher gain Ge in Q2, then swapp all you have and listen to them in Q1, you'll get an idea of gain Vs sound pretty quick. Then you can diddle more transistors...lol.
 I built 'em like this, then I have a FF transistor test board, one of them I have put clay candle sticker stuff to hold the components in, another I just bent a matchstick once back over, stuffed that in the IC socket center 'box' with a dab of elmers, another dab of elmers to between each end of the matchstick/transistor on either side of the socket...I have this special lead bending process where they don't fall out anyway..lol.. but use these tie 'um down anyway methods.
 The Rangepig is a gain controlled [discrete pair of bipoalar] darlington, plunked in a RM circuit. Should be a bit noisier with the added gain and multiplying the noise x2 transistor, [ie noisy transistors is gained up = gained up noise, no real cure for that], but any 1 or 2 transistors candidates you have [bipolar and NPN/PNP...polarized correctly] can be put in there, one or two at a time, so you can still get your 'special egg Ge' then use whatever sounds best, nice testboard for any 1Ge, or 2 Ge darlington pair [w/gain attentuation control] you want to try in an RM.  
 The 'lasties' can be used if they test as diodes, connecting them with B/E only...wherever a Ge diode can be used.