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Could this be a mistake when they label them? Could the red dot be misplaced because of some factory error? The curious is that all the transistors with less gain have the expected pin out and the ones with higher gain have it reversed. I think i'm going to try them again in both positions and i will use the one i like the most because as i said the sound is a little different.

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I don't know if there's something wrong with them but i did test them in a treble boost circuit and they sounded good to my ears. But i want to be sure about the transistor pin out because, at least with this circuit, they worked in any of the 2 positions but soundwise they were a little different.

Hello.
Some time ago i found some some OC140 transistors in a local shop. They seem to be made of black glass, with the word "OC140" and below that the letters "VWY" both words in white and they have a red dot near one of the transtistor legs.
At radiomuseum.org they say OC140 are "made by Valvo - Germany (...) NPN germanium junction transistor Intended the switch and / or bi-directional applications. All-glass body, blue (?) Indicates dot collector. Also made by Philips and related manufacturing plants".

I tested them with my PEAK Atlas DCA55 and i've got diferent pin out readings according to their gain.
The transistors with lower gains (Hfe =54, 55, 58, 62, 68), the pin out would be the expected: Red Dot = Collector -> B -> E.
The transistors with higher gains (Hfe = 96, 126, 160 and 162) the pin out is inverted so Red Dot = Emiter -> B -> C.
Does anyone experienced this or does anyone knows why this happens? And what is the real OC140 pin out?
Best Regards

You lucky bastard 

My best score was probably a MIJ Silver Screw "long dash" Boss DS-1 that cost me 20€. I then traded it for a Wren and Cuff "The Caprid" with the builder that makes these wonderfull pedals (a very nice guy buy the way).

 

Yesterday i came back to the store where i bought the vintage transistors and i spoke to the owner. I told him i was looking for some old transistors and he told me he had lots of old stuff (transistors, capacitors, resistors etc) in his own house, that came from an old electronics store that was going to close. He bought all the store's stock and stored it in his garage. He only brought some of the old stuff to his current store because no one is looking for that old components anymore. He doesn't know exactly what type of transistors he has but he told me that i can go tho his house and search in his stock to see if i find something i'm looking for. I hope i find some good stuff

Thanks 
I have to go there again to see if i find some more old stuff.

A couple of days ago i used something like the envirotex material (other brand that i found in a local store) for the first time, along with transparent adesive paper for the graphics and something funny happened: the ink that i used to paint the enclosure (acrylic spray paint) kinda started melting down and created some kinf of "melting ink" finish. I kinda liked but it wasn't the result what i want to get. It also create a light blur in the graphics, making the traces a little less defined. I think there was some kind of chemical reaction between the ink and the envirotex like material that i've used that dissolved or
diluted thepaint.
Did any of you have experienced something like this?

It seems i really found a little "treasure" yesterday (and i've only been in the store for 20 min.). They still have a lot of old stuff. I didn't have the chance to test them so i bought as much as i could. Maybe i can find even more i just need to go there again with more free time.
Now i really have to test them (i don't have any proper device to test the transistors so i'm tinking of building a small transistor tester as said by R.G. Keen).
I can search in the store any specific item if any of you want. Just drop me a message and i see what i can find.
Thanks to all for your advices.

Hello.
I need your fuzz expertise.
Today i found some old transistors in a local store. Here is a list of them:

- OC 42 X10
- OC 44 X2
- OC 45 X5
- OC 70 X1
- OC 71 X6
- OC 74 X2
- OC 75 x1
- OC 81 X1
- OC139 X5
- OC140 X10
- AC124 X6
- AC127 X2
- AC128 X10
- AC187 X3


I have to test them for gain and leakage but i need to know what values of gain/leakage are good or bad to use in a fuzz and also what kind of fuzzes i can build with these type of transistors.
Any help will be appreciated.

Amazing layout, amazing clean build, amazing finish.
Sign me in for a board too!

Thank you all.

midwayfair: The PCB is an old fabbed one. The guts shot will be added soon.

Another great project from Madbeanpedals. I made some of the suggested mods: One of the channels has the Hi-Gain mod, i left some capacitors with sockets so i can change them if i want and instead of using internal DIP switches to select/change the diodes i used external mini toggle switches. It's more "user friendly" in my opinion. I'm not totally satisfied with the finish because i bought a very shitty gold paint that is very fragile even with the clear coats that i applied so i will soon have relic looking pedal 

My 4th pedal so far. I decided to give it some kind of a "Cornish look" with a big enclosure, fresnel raised LED Lens and Chicken Head Knobs. Great tones out of it but i'm still messing arround with the diodes (i socket them) to see which i like the most. I don't have guts shots for now but i will post them as soon as i take them.