Nautilus - Mutron iii

[madbean]

This has occupied most of my week so far. My original prototype had numerous errors which kinda bummed me out. So, I decided to start over and do a single sided layout. My first attempt had the envelope detector set up more like the Meatball, with extra Attack and Decay controls. The LED drivers were pumped through a 2n3904 transistor with the base being fed by the output of the envelope. I managed to make a new mistake on this layout due to swapping an op-amp. But, I figured that out quickly and re-routed what I needed to under the board.

Anyway, this approach actually did not work out very well- The transistor seemed to be driving the LED too hard and it would sometimes "freak out". So, I removed the 2n3904 and got it going. But, the Attack and Decay controls just were not doing it for me. So, I started over again with another layout, this time setting it up more like the original. Now the envelope drives the two LEDs on the Vactrols directly and I added a Sweep control, which sets the intensity (this is Rx on R.G's "Neutron" project). That did the trick! There are a couple of other mods. I reduced the input gain a bit since at the very top of the gain it seemed to crap out. That was done just by increasing the input resistor a bit. The other mod is that the unit is true bypass, and an inverted output stage was added with a gain trimmer in case one needs a little more out. This means the input and output are now in phase, unlike the original Mutron.

Overall, I am really happy with it. The double sided layout is already done, and it is a variation of the layout you see here. The double sided layout will board-mount the pots and two switches. The rotary switch will be wired (only requires 4 wires).

The etch on this one came out really nice, even though I misspelled the name. That was probably because I rushed that like hell---I only spent an hour on it from design to finished etch. But, she looks real cool. Mostly due to the Cthulhu drawing which I swiped from the web.

[gtr2]

THIS IS AWESOME!!!

[midwayfair]

Very excellent. This and the Fishhead are extremely high on my wish list. (Hint hint!)

Thanks for putting a bunch of hard work into this project. I'm sure this was like a vacation after the meatball, though!

[bangerang101]

Dude Brian, this is great! Mutron iii is epic... awesome job man.

Cheers!

[spaceboss]

AW YEAH! 

[jubal81]

Love the changes/mods to the original project. Looking forward to getting one of these going!

[2tonewarrior]

Awesome! nice finish. Count me in for the first series of PCBs

[njkke]

Really nice job, do you release the single side version with the nautilus documents?

[sprayfe]

Beautiful work, I would love to know about artwork as well
You are the masterbean!

[madbean]

Thanks! The PCB etching artwork will be included in the project doc when the manufactured PCB is released.

[Haberdasher]

yes!  I'm looking forward to this puppy.

[nzCdog]

Wow... thats impressive!

[eldanko]

This rocks! How's it compare to your meat sphere build?

[irmcdermott]

oh gosh... i've been looking at doing a Mutron for a few weeks now... just may wait for this now

[jkokura]

Yeah, I want this one.

Jacob