Super-Freq » Modulation

Casualty 4 Phaser MKII

admin — Mon, 22 Mar 2010 04:42:04 +0000

Just tested this one again. My mistake the shape pot is working. It seems to me that the Width pot seems to square off the LFO wave form as it is turned up. With Width all the way up the LFO seems to produce more of a square wave.

Casualty 4 Phaser working

admin — Sat, 20 Mar 2010 23:16:08 +0000

Here’s an image of the Casualty 4 Phaser. Wired everything up. After figuring out that I had forgotten to connect the ground wire from the jacks to the board everything seems to be working. Initial observations. The Shape pot seems to do nothing. The Width pot seems shape the soft triangle into a trapezoidial square wave. The phase sound is pretty rich. Need to test some more…

FSH-1 PCB

admin — Mon, 15 Mar 2010 07:05:58 +0000

This will be the fourth time I try to build one of these. I made a PCB for the original using the layout from GGG. I never finished this. Then I built and finished a second using the layout from UStomp.com. I couldn’t get this to work. I forget what the problems were, it was more than a few years ago. Franciso Pena, of Tonepad.com came up with a new and improved version that used 13600 in place of the 3080s. I built the first version of this. It was the most successful of the bunch. It worked pretty well but had two problems that I couldn’t seem to solve. With mine you could hear a ticking from the sample rate oscillator and the sweep switch refused to work in one direction.

Anyway, I found a sheet of PnP that I had printed sometime ago of Francisco’s second version of the FSH-1. I thought what the heck, might as well give it another try.

Casualty 4 Phaser

admin — Mon, 15 Mar 2010 06:21:27 +0000

Here’s interesting phaseshifter idea I found over at Circuit Workshop. The Casualty 4 is an OTA based phase shifter with two modulated stages and two fixed phase shift stages. This looks like a pretty interesting project.

Looks like you can fit this in a B sized box but there doesn’t seem to be enough room left over for a battery.

Here’s a picture of the populated board.

Tremolo FX Loop

admin — Sat, 06 Jun 2009 20:26:20 +0000

This is a first draft of an idea that I have been thinking about for a few months. It’s a Tremolo that pans between the input signal and the signal coming through the FX Loop. If no signal is coming in to the FX Loop it would act as a normal Tremolo. Otherwise it would be cycling from the straight to the effected signal.

The main idea was taking from Nicolas Boscorelli’s Stompboxology Tremolo-Matic X. I make no gaurantees that this actually works as I haven’t built it. This is just a first pass to get the idea down.

Tremolo-Matic X

admin — Sat, 06 Jun 2009 05:03:48 +0000

This is Tremolo-Matic X from the Tremolo Issue of Stompboxology by Nicolas Boscorelli. I have redrawn the schematic to make it easier to read. Hopefully this will be helpful to anyone attempting this project. This is Tremolo that pans between a treble and bass signal. It inlcudes controls to set the level for both the bass and treble, rate and depth.

I built mine from the PCB layout posted by Morocotopo at Diystompboxes here. This lay out worked well for me. Though it looks likes it isn’t finished as there are a few extra pads that don’t quite make sense. The layout does work. I have built it myself.

It sounds pretty good. I made a few changes. First I changed the Rate pot to 100K to get a more useable range of speeds. With the original 25K pot the slowest speed was not very slow. I like the sound of slow tremolo. The 100K pot is shown on my vsersion of the schematic. speaking of the rate, I’d like to get a slightly faster rate at the fast speed and a little slower at the slow end. I think I will be playing with R21, R25 and C15 a little more.

The other mod, not included in my schematic, is to decrease the gain on the input stage. Basically this comes down to decreasing the value of R14. With the original value of 470K you get a little bit of clipping with hot pickups. I haven’t decided on a value yet.

Note the, input stage is inverting. Which presents a lower input impedance than would normally be acceptable. But it seems to work OK here.

Also note that there are a few parts list as optional feed through bias or something like that. These parts include a 5V regulator and adjacent parts. I left these out of my build, and everything worked fine. I left these out of the schematic posted here.