What Goes Up Must Come Down V2

The exact same tube preamp/tremolo circuit as the first layout, however this time fed into a more powerful amplifier IC. This is definitely the better of the two versions of this design, and while you do lose the gain control found on the first layout the amount of volume more than makes up for it. Speaker on this one is 4ohms. The speaker connections must remain isolated from any metal enclosure.

What Goes Up Must Come Down V1

My second little 'tube amp', this time with onboard tremolo! Now it's not great but it gets the job done... I suppose. Tube really needs to be a 12au7, and the IC needs to be the LM386N-3. The LM386N-1 will work but it has a slightly lower output capability. Speaker is 8ohms. These little amp ICs are really good at small speakers but if you want something a tad more useable I suggest building version 2 of this design.

10x LED Chaser/Follower

The name/title says it all. Circuit is a typical LED chaser circuit comprised of 10 LEDs. Another design lifted from one of the pages of Forrest Mims many books. I used this exact circuit to indicate the speed of a pt2399 delay using a stacked 100K potentiometer. One level of the pot controlled the speed of the actual delay circuit, while the other level of the pot simultaneously controlled the speed of the LED chaser. The times didn't exactly line up but it's really close and the idea/effect is really cool. This also isn't too far from how one would go about making a sequencer or 'music box'. 

Terrible Tubes

A powerful preamp (of sorts) using a pair of 5840 subminiature vacuum tubes running at 36v. The gain and tone controls both have a wide range of of useable settings/sounds. When you max the gain knob you'll really want to call this a fuzz but everything below that is somewhere between an overdrive and a preamp. The switch isn't the most noticeable in all settings but it gives two gain settings ultimately. If it's got subminiature vacuum tubes involved you can almost guarantee it has something to do with Rick Holt/Frequency Central, this circuit is no exception. 

 

12v Tripler

This circuit takes 12v+ on the input and gives you almost 36v+ at the output. Some of the tube circuits I've been playing with require running the heater at higher voltages so having this laying around has been pretty handy for experimenting with "headrooms". 

Buffer Fucker

 This is a guitar pickup and controls simulator. When using the classics (tonebenders, fuzz faces, univibes, etc) its a known fact that they pretty much require being placed first in the signal chain. Their simple circuitry cant handle being downstream from our modern effects, in walks the Buffer Fucker. The little transformer has a primary winding with a center tap, this emulates the actual coil (single or bucker), the two trim pots acts as your guitars volume and tone controls, the remaining parts acts as the tone cap and any further capacitance and resistance given by your guitars internal wiring and patch cable. Placing this circuit at the input of your "classics" will allow you to set them anywhere in the chain.

The Good, The Bad, The Ugly

Three oscillating drones from a single IC. The two first oscillators have a pretty wide range of frequency, while the third and final drone is substantially narrower. The pitches can be matched or pushed just slightly off balance with each other to create some really cool tones. This is a design pulled straight out of one of Nic Collins electronic experiments books. Not all 4093 chips are equal and I went through quite a few before settling on one that sounded good and behaved accordingly. 

PenToad +

Similar to the "Pentoad" boost circuit, but this version introduces 1N60 diodes to clip the signal. Having the gain turned down will give you the sound and feel of the original pentoad circuit, whilst doing the opposite gives you a mid gain overdrive type sound. Cranking the gain knob will get you into fuzz territory. For my personal build I put two of these exact circuits in series in a single enclosure, gets really fuzzy that way. It should be noted that while the 5678 will work in the original, it will NOT work in the "+" version.

Topsy-Turvy True Bypass

This is a weird one. A means of turning on an effects pedal/circuit via.....gravity? The circuit utilizes mercury/tilt switches in place of the typical mechanical throw switch, and takes place of the 3PDT footswitch in most pedals. When the entire circuit board is parallel to the earth or flipped 180 degrees on its 'x' axis (upside down), the secondary circuit will either be ON w/LED or in TRUE BYPASS. I've used mercury switches in the past to make SPDT, DPDT, and 3PDT switches using 2, 4, and 6 individual mercury switches respectively. I doubt many people, if any, will build this as its simply not very useful. Just a cool project.

PenToad

A subminiature vacuum tube boost circuit. These little tubes are called 'pentodes' and are highly microphonic so be prepared. Original schematic was made by Frequency Central's Rick Holt and can be found on various archival forums. Its a really nice "warm" tube sounding boost and breaks up the monotony of another Valvecaster. I have another layout based around the same schematic but introduces some clipping diodes and gets pretty raunchy, appropriately called the "PenToad +".

How Much?

This circuit will behave as a VU meter. Capable of powering 5 individual LEDs or 10 LEDs arranged in serial pairs. The louder the signal that gets passed through the circuit directly corresponds to how many LEDs will illuminate and for how long. This is one of the first circuits I ever made myself, and remains dear to my heart. It's essentially the schematic given in the data sheet for the IC, but with a few altered values to work with guitar/bass.

Atari Punk Console

 A step generator circuit designed by Forrest Mims. Two oscillators give various tones capable of increasing/decreasing in equal "steps". This layout uses the 556 chip but it is possible to accomplish the same feat with two 555s. Forrest Mims is somewhat of a personal idol. He is/was just a regular guy like me without any real formal training who went on to have a successful career in electronics. Hes published several DIY books and journals and a lot of my work has directly stemmed from his projects.......just go check out his works.

Traffic Signal Simulator

Circuit runs three LEDs in a common traffic light pattern. Green(go) light will illuminate for a period of time, then a brief illumination of the yellow(caution) light, followed by the red(stop) light with an almost equal rate of illumination as the green. 

Poorboy Pocket Piano

 A rather simple and rewarding “synthesizer” based off/around the infamous Atari Punk Console created by Forrest Mims. It more or less operates as a chromatic piano. This layout could also be frankensteined into a pseudo Stylophone type device with a little know how. 

Loud!

The “Loud!” is a low watt/low volt tube amp. The TDA7052B is a little hard to come by but I believe the TDA7052A will suffice. The preamp section is a Matsumin Valvecaster providing gain and tone controls. That’s then pushed into the amplifier IC and out to the speaker(s). The speaker positive and negative terminals must remain isolated from an enclosure as to not ground out the signal. The taper of the volume pot might be altered as well. In the end you get somewhere around 3watts, give or take.