By popular demand, here's the PAL 800, a well regarded Marshall-in-a-box circuit. Should fit nicely in a 125B. Schematic here. All the trimmers except the one just below the Volume control are for biasing the JFETs. Start at 4.5v on the drain of each JFET and adjust by ear from there. The other trimer is for smoothing out the output signal.
Very nice. Would love to see the PAL959, if anyone has the time.
ReplyDeleteSIDE NOTE: This is almost identical to the JCM800 JFET circuit provided by Electrictabs, YEARS ago on one of the DIY pedal sites. Only differences one the PAL800 is some of that filtering at the end, and the added presence control.
this pedal is awesome, I think I'll build it, I'll just omit presence control 25kb and 100n
ReplyDeleteYay!
ReplyDeleteThanks!
Would this work with 12v?
ReplyDeleteYes, though you'll need to adjust the trim pots to 6v when biasing.
DeleteI'd like to build the new version: PAL 800-V3 GOLD Overdrive.
ReplyDeleteIt has a second footswitch to get a sort of low input and high input mode; a toggle switch for the MOD #34 sound; and a toggle switch to get different voicing.
I guessed it's about the same PAL800 basic schematic with some little mods and adding, but it seems to have a bit of too much extra parts. The schematic is unknown.
You can call it verified. Sounds like it should. the tone controls seem subtle and the master tone control doesn't do as much as I was expecting either. I don't have the actual one to compare it too. It sounds great! Probably just like the amp.
ReplyDeleteThanks for verifying!
DeleteI built the JCM layout with the high/low input footswitch that's on Tagboard. The eq wasn't massively effective on that either.
DeleteHello, can you make a simple Boss MT2 pedal layout and schematic?
ReplyDeleteor can someone tell me the layout or the site on google which is easy to understand.
too hard to find layouts and schematics on google.
Thank you from Indonesia
Sorry my english is so bad
https://rumunsko.mypage.cz/menu/kytarove-efekty-a-pedaly/mt-2-metal-zone
DeleteI have been searching on the same subject and came across this web site. Auto-translate helps a lot.
This web site gave me so many good pedals and understanding on building and repairing them, this at least helps admin friend on handling requests. :)
Thanks, i will try :)
Deletewhich pot is to adjust the Drain on Q4
ReplyDeleteJust finished, fat distortion like a marshall, sounds amazing. Can you double check the bass pot, I checked 3 different schematics and it is 1M instead 250k
ReplyDeleteAnd just for reference, I used set Q1=3,9V, Q2=6,9V, Q3=4,0V, Q5=5,6V, Q6=2,7V. using a 9v power supply
ReplyDeleteThis comment has been removed by the author.
DeleteDoes it still need a cab simulator,,,?
ReplyDeleteDon't need cab sim,but is cool to have a cab sim or IR impulse with this pedal.
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DeleteHello, could I use j202 instead of j201?
ReplyDeleteIs anybody out there?
DeleteUse j201, 2n5457,ks30
DeleteHi, I can't find this pedal in the transfer Image Library.
ReplyDelete