It's Fuzz Friday time again, and this week I give you the Ampeg Scrambler. This one's a pretty rare one, even back when it was originally made in the late 60s. It's a pretty crazy octave fuzz with a clean blend. Originals used 2N5306 for Q1, 3, and 4, and a BC169 for Q2, but those could be difficult to source, and it works fine with modern equivalents (mind the pinouts if using original transistors). If you want to add a master volume control, use a 100k pot (adjust to taste) and wire lug 3 to the Out pad of the board. Lug 2 is now your output, and lug 1 goes to ground. This sounds pretty cool on bass as well as guitar.
I think it is not the problem, all my components are new. I already did some tests and could not find the problem right now. This layout is checked? Thank you a lot.
Layout checked! Working fine! The mistake was mine, i wired wrong the transistors (I used 1n5302 instead the MPSA14, so i forget to change the terminals... But now all is working fine. I had a trouble on the texture pot. It was not working, but i found a way. I removed the pot and jumped the terminal 2 and 1. Removed the 8k2 resistor and wired up a A500k potentiometer with a 1k resistor in series with his terminal 1. Working very fine the effect, i liked a lot. :)
Hi, I did it and it works really well. My question is if you can change the C1(10n) to a higher value to increase the bass? What value do you recommend?
schematic?
ReplyDeletegoogle?
Deletehttp://www.maxvolmag.com/wp-content/uploads/2013/04/Ampeg-Scrambler-Schematic.png
excuse question. this functional layout?
Deleteexcuse question. this functional layout?
DeleteNot is working for me :/ Only a buzz sound on the amplifier.
ReplyDeleteI got 9v measures on the pot pads. Seems i have a short, no? But i checked my board for 4 times and not found the short '-'
ReplyDeleteYeah, I would think something's shorting. Could be a bad component somewhere
DeleteI think it is not the problem, all my components are new. I already did some tests and could not find the problem right now. This layout is checked? Thank you a lot.
DeleteLayout checked! Working fine! The mistake was mine, i wired wrong the transistors (I used 1n5302 instead the MPSA14, so i forget to change the terminals... But now all is working fine. I had a trouble on the texture pot. It was not working, but i found a way. I removed the pot and jumped the terminal 2 and 1. Removed the 8k2 resistor and wired up a A500k potentiometer with a 1k resistor in series with his terminal 1. Working very fine the effect, i liked a lot. :)
ReplyDeleteLet me know any questions.
Giovanny it cant work for me and i Did all your modifications
DeleteAny advise?
Anyone knows if this pedal works?
ReplyDeleteWorked fine at first try!
ReplyDeleteAdd some good dirt to your bass.
Used:
BC517 instead of MSPA14,
2N3904 instead of 2N5088.
Sounds great.
mine work excelent too! Used:MSPA14, 2N5088.
ReplyDeleteHi, I did it and it works really well.
ReplyDeleteMy question is if you can change the C1(10n) to a higher value to increase the bass?
What value do you recommend?