Using Transistors Pulled From Old Gear

[emilyandmiles]

Can anyone help me find a purpose for these?
BC 148B
BC 148C
BC 149C
BC 158C
BF 195C
Any ring a bell from a fuzz layout maybe?
Many thanks.
www.dropbox.com/s/yiydabv0spb3cf9/IMAG0009.jpg

[thelonious]

You don't have to match the exact model numbers. Just google the datasheet to see whether they are NPN or PNP devices, breadboard a silicon fuzz circuit, and see what they sound like. The NPN ones would probably work well in a bazz fuss - scroll down to where it says "homemade darlington". In my experience with the BC devices, the '48 or '49 devices are NPN and the '58 or '59 devices are PNP, but it's always good to check.

[duck_arse]

like thelonius says, they will substitute for the bc107/547-8-9 and bc177/557-8-9 series. the "c" is the lower noise higher gain batching, "b" is as ordinary as you will find.

the bf195 is an HF amp, in my old book.

put em into some colorsound circuits, pass the sot25 cases off as extra mojo, of course.

[emilyandmiles]

Thanks thelonious
I've an old enclosure with drill holes for 3 pots and a switch that's crying out for something.
Sure I saw a voltage inverter daughter board using a 555 for running pnp with my other stuff somewhere.

Nobody recognizes them from any layouts they've seen around?

duck_arse: That's great. I think I've everything in for a one knob fuzz build with some cap switching shenanigans.

[duck_arse]

I have a pdf from dirk hendrix, the only thing I could find on my system, but couldn't find it netweb-wise. it is marked thus:

PROJECT: COLORSOUND OVERDRIVER VINTAGE AND REISSUE
DATE: 19 APRIL 2007
DRAWN: DIRK_HENDRIK

it shows some "bc148L", which I think might be a mis-pront.

I'm 100% almost certain I have seen a picture of an ancient fuzz board w/ sot25's in, but I've seen a lot of pics of boards.

and this turned up:
http://www.diystompboxes.com/smfforum/index.php?topic=59038.0

[thelonious]

Sure I saw a voltage inverter daughter board using a 555 for running pnp with my other stuff somewhere.

Yep, you can definitely use a 555, but frequency-boosted charge pumps like the ICL7660SCPA or TC1044SCPA are quiet and relatively foolproof. IMO it's not worth it to mess around with a 555 unless you have a bunch of them sitting around and are hoping to get rid of them (or unless charge pumps are tough to source in your corner of the world).

But keep in mind that you don't have to use a positive ground scheme to make use of PNP transistors. For one thing, you can use those BC148/BC158 together in a Sziklai (complementary) pair, which might be what they were doing to begin with in the circuit you pulled them from.

[emilyandmiles]

That old thread was very interesting.
Similarly these are from an old Roberts Radio (now a Noisy Cricket)... www.dropbox.com/s/hvyqwoxo1qjupe4/IMAG0004.jpg
Thinking of going with the sockets and Colorsound fuzz route. Would be interested to see that PDF.
Up to my wrists in a TubeReamer at the mo.. but will post fuzz findings soon.

[thelonious]

Would be interested to see that PDF.

Me, too. Duck, if you are willing to upload that PDF to Google Docs or Scribd and share a public link, that would be super cool...

[vigilante397]

Similarly these are from an old Roberts Radio (now a Noisy Cricket)... www.dropbox.com/s/hvyqwoxo1qjupe4/IMAG0004.jpg

Hands down the coolest Noisy Cricket I've ever seen. Well done

[zombiwoof]

I have a pdf from dirk hendrix, the only thing I could find on my system, but couldn't find it netweb-wise. it is marked thus:

PROJECT: COLORSOUND OVERDRIVER VINTAGE AND REISSUE
DATE: 19 APRIL 2007
DRAWN: DIRK_HENDRIK

it shows some "bc148L", which I think might be a mis-pront.

I'm 100% almost certain I have seen a picture of an ancient fuzz board w/ sot25's in, but I've seen a lot of pics of boards.

and this turned up:
http://www.diystompboxes.com/smfforum/index.php?topic=59038.0

If you're talking about the "L" in "BC148L", it indicates a different pinout than the B or C versions (at least that is what I've seen in other transistors).

Al

[duck_arse]

the "L" is a real neat trick to play on the unexpecting. I thort it was a gain bucket. it didn't appear on the bc147/8/9 d/sheet I saw though.

I was scratching at the wires last night, and I even found his site. so, here is a link to "that" pdf.
http://www.dirk-hendrik.com/temp/Colorsound_Overdriver.pdf

there is a bunch of other circuits here:
http://www.dirk-hendrik.com/techstuff.html

I also found mr hendrik is a member here. (sorry for the mis-spell, if you see this thread ....)

e+m - so, now you have increasing piles of parts from a radio, you find they are eminently suited to building .... a radio. and the case? perfect for a ... a .... a radio. etc. still, maybe a practise amp or something.

[thelonious]

so, here is a link to "that" pdf.
http://www.dirk-hendrik.com/temp/Colorsound_Overdriver.pdf

Cheers!

[emilyandmiles]

e+m - so, now you have increasing piles of parts from a radio, you find they are eminently suited to building .... a radio. and the case? perfect for a ... a .... a radio. etc. still, maybe a practise amp or something.

That's the plan... already used the enclosure for a Noisy Cricket... www.dropbox.com/s/hvyqwoxo1qjupe4/IMAG0004.jpg

As for the parts... hoping to get a couple of interesting fuzzes out of this lot. www.dropbox.com/s/nbp6yucn0k7xmu8/IMAG0016.jpg

Will make sure I post some photos when done : )

[zombiwoof]

the "L" is a real neat trick to play on the unexpecting. I thort it was a gain bucket. it didn't appear on the bc147/8/9 d/sheet I saw though.

I was scratching at the wires last night, and I even found his site. so, here is a link to "that" pdf.
http://www.dirk-hendrik.com/temp/Colorsound_Overdriver.pdf

there is a bunch of other circuits here:
http://www.dirk-hendrik.com/techstuff.html

I also found mr hendrik is a member here. (sorry for the mis-spell, if you see this thread ....)

e+m - so, now you have increasing piles of parts from a radio, you find they are eminently suited to building .... a radio. and the case? perfect for a ... a .... a radio. etc. still, maybe a practise amp or something.

I only knew about the "L" suffix because of the BC183L transistors that were used in some silicon Fuzz Faces, I found that the leads had to be twisted to fit the board holes in the correct alignment, vs. the transistors with no suffix, or B or C suffixes.  So I figured it meant that the pinout was different.  When you look at the spec sheets for different transistors, it usually has an explanation for the different suffixes for ordering purposes.  The only gain suffixes I am aware of are the "A, B, and C" ones, indicating escalating gain ranges in sorted transistors.  Ones with no suffix could read anywhere within the full gain range of the specific transistor.

Al