DeadPool Transistors

[K3yPr0gg3r]

Hi,

I'm starting to build Deadpool soon. The build doc suggests the 2n3565/PN3565 hFE be around 260. I went out and bought a cheap DMM with hFE at Harbor Freight today, (already have a good UNI-T DMM with NO hFE), and I'm puzzled by my readings. All I have are PN3565s broken up into 2 seperate bags...I think because one bunch is from Tayda. Anyway, the one bunch registers around 412 - 580 hFE while the other measures around 201-218. I have 2 (218s) so I'm going to go with those unless I should go with the higher value.
Not sure about what's optimal as far as hFE goes, unlike my understanding of diode forward voltage, (germanium anything around .03, silicon around .07). Measured BC550s I got from Tayda as well, and got 411 -485. If someone could give me a heads up on hFE, and IF my measurements are correct or not that would be helpful.

Thank you

[Matt]

I'd check the data sheets.

[m-Kresol]

hFE readings are often more or less close in one batch and then total different in another. as long as you measured them correctly, I see no reason why you shouldn't use those two in your build. I'd advise to use sockes though to make sure.

[Bret608]

I have a Harbor Freight DMM too, and I've found the hfe tester works well for silicon transistors. I've compared it to much more expensive ones they have in the electronics lab where I work, and the results are pretty much the same.

I think PN3565s have higher gain than the old 2n3565s, so I'm not surprised most of yours measured on the high side. The 2n3565s I have on hand at the moment range from 190 up to about 360 hfe. So I think trying out those 218s you have first would be the way to go. This is on the list of circuits I'd like to try as well.

[K3yPr0gg3r]

Bret, thanks! As a newer builder, (just completed my 10th build), I try to follow the docs as closely as possible...sometimes banging my head on the proverbial obsolete component wall. I'm learning that alternatives can lead to working pedals as well, (being "close" to the stated doc listings).

[Bret608]

Oh for sure! Sometimes you'll find the alternatives sound better even. I'll bet 2n2222 or 2n3904 could sound great in the Deadpool. I like metal-can 2n2222 for a common, inexpensive transistor type that has a bit of that mojo look. I used some for most positions in a modded Kay Fuzz I built and they sounded great. But you know, I have been saving my last two 2n3565s for an Os Mutantes build. If not an etched Deadpool, then the new fabbed version from Fuzzdog.

[Mantaray14]

I just built a Deadpool and used some 2n3904s I found at rat shack.  Didn't test them just swapped them around till it sounded okay.  Looking forward to trying some other trannies. Not to hijack the thread,  but does anyone know what Germainium doides I cause use in this circuit? I've got some silicone in there now...