New Project Day: Graymark Fuzzbox

[Mark]

So, I made a thread like a couple weeks ago about getting one of these 12 dollar electronics kits made for beginners, because one was a fuzz. I remembered it being really shitty but the again, it was the first thing I ever soldered, I gave it the benefit of the doubt and asked my electronics teacher if he would order a kit for me while he was ordering the 1st year students's kits. It came today, so I'm going to post the schematic and post pics and progress here, and then eventually I'll post a demo here. This will also the place where I put modifications of the circuit, so yeah :P

So, the first thing I found interesting is that they run this circuit on 18VDC, instead of 9... Also, the bypass circuit is old-school to accommodate what looks like an SPDT switch... but then why do they use a DPDT switch for the power? Those diodes aren't there for clipping (it doesn't seem like), so WTF are they there for? They ARE in the signal path but they are definitely not in the arrangement you would expect to see...

Also, I totally didn't even realize that none of the values of anything is listed. I'll scan the other page tomorrow (it's at school right now)

[Scruffie]

That's not 18V it's a Bipolar Power Supply for the Chips, you could achieve the same thing with just 9V & a MAX1044 Chip or simmilar or just redesign the circuit a little.

Second, I think the Diodes are working like a voltage clamp to drop the voltage going into the second IC...

The DPDT on the power is just showing how it would switch like with a Stereo Jack would turn your effect off when you pulled out the jack.

[Mark]

That's not 18V it's a Bipolar Power Supply for the Chips, you could achieve the same thing with just 9V & a MAX1044 Chip or simmilar or just redesign the circuit a little.

Second, I think the Diodes are working like a voltage clamp to drop the voltage going into the second IC...

The DPDT on the power is just showing how it would switch like with a Stereo Jack would turn your effect off when you pulled out the jack.

OHHHHH WHY didn't I recognize that! That makes a lot more sense...

[Mark]

hm, I'm going to order another one and breadboard it, 1) because the PCB that it came with is total shit and 2) because I wanna fuck with the circuit.

[nbabmf]

Tonepad has a good PCB layout for a bipolar power supply using the MAX1044. It's pretty easy to convert to a perf layout. That's what I did for the Craig Anderton ring modulator last week.