• PT2399: nuances…

    i’ve been wrapped up in Jeep repair lately as there’s some sort of issue prevent the beloved XJ from firing up. i have, however, in the meantime had some time to work through my initial modulation tests on this version of the PT2399 circuit and nail down a lot of the bugs. the initial problems…

  • initial test of a modulated PT2399 circuit…

    a breadboard version of some PT2399 modifications i’ve been working on. there are a lot of DIY schematics that utilize the PT2399 (Magnus Modulus, Echo Base delay, Rebote, etc.). i’ve been interested at trying my hand at modulation techniques recently. i made a simple LFO circuit based on the findings mentioned in a previous post.…

  • MOSFET overdrive… final build?

    i might add some labels for the pots and contact info, but it’s done for the most part.

  • simple LFO circuits…

    i was reading over this thread on diystompboxes.com about building an analog LFO circuit for some wild noise idea i’ve got brewing in the back of my head. i started messing around with some of the schematics on there and got a drifting saw wave out of it after a while. i was trying to…

  • TDA2040 PCB layout…

    backlit PCB layout of the TDA2040 solid-state amp i’ve been working on. i’m still using perf boards until i wrap my head around designing PCB layouts in EagleCAD. i do a lot of work in the dark.

  • TDA2040-based amp schematic with EQ…

    well here’s the first draft of the simplest medium powered solid state design i could muster. TL082 can easily be substituted with a TL072 which is probably better anyhow (i just have all these TL082s laying around). the power supply i’m using more like 14-15V. both ICs should easily be able to handle up to…

  • TDA2040 amp prototype…

    prototype of a 20-watt TDA2040 based amplifier that i’ve been working on. running a 12-volt power supply and it’s surprisingly loud.

  • Sinometer 10MHz oscilloscope…

    simple. cheap. a thing of beauty to add to the ol’ workbench.

  • experimental PTT signaling switch…

    this is an experimental circuit i threw together today. i’ve been working on getting a VOX circuit to work with the Yaesu FT-60R (VX-3R, VX-5, etc.) and Soundmodem on the ol’ Gentoo box. it’s working well, but test packets have been a little iffy.