FISHERS (project pt.4)

 -DESIGNING CIRCUITS:

Designing the circuit boards is by far my favorite part of any project. I am still using an old version of KiCad 5 that I have really had no reason to upgrade for the last few years. I have created my own custom footprint libraries for all of the parts I use, and the last time I upgraded KiCad it was a disaster, so I'm happy to stick with the old version. I'm sure I am missing out on new features, but as is the case of all of my other old-working software versions like CorelDrwaX5, sketchup2017, Mach3, Arduino1.8.5, and even Windows10, as long as it still works, there is no reason to upgrade!..

FISHERS (project pt.3)

 -PLANNING THE INTERFACE:

The first step in designing the faceplates and arranging the hardware layout, is taking careful measurements of the keyboard enclosure, and drawing it up in my design software. It is important that the working perimeters of the drawing are as close to accurate as possible, so that I know the added hardware will all fit properly.

FISHERS (project pt.2)

 -PLANNING/BREADBOARD STAGE:

VOICING

I was hopeful that the circuit would be a good candidate for circuit bending, since there are so many big chips, and lots of analog circuitry. Unfortunately, there was really just not much that I could find that was useful. I tried bypassing the data lines to the ROM chip to try and get some kind of access to the piano voice sample using all manner of counter/dividers, pulse-delays, and shift registers, but it seems that the way that the piano-sound data is parsed with the program memory is too closely multiplexed. At least that is what I concluded from my repeated failed attempts to do anything but crash the whole system again and again. I still think it would be possible to bypass the piano-sound data somehow, but seeing as how the sample-depth is only 8-bit resolution, I can assume that there would be a very limited amount of sound variations, and would probably not justify the hardware needed to achieve them...

FISHERS (project pt.1)

 1989 FISHER PRICE 3810 "REAL-SOUNDS PIANO" 

The Fisher Price 3810 Piano was a common toy during the early 90's. They were well made, and are still available in good condition on ebay, and sometimes can be found at thrift stores. The keyboard measures around 23 inches long, 8 inches wide, and about 2 inches thick. There are 32 keys that are slightly larger than standard mini-keys of the era. Despite the sturdy build quality and uniquely 90's design, the sound quality and functionality of the toy is curiously limited...

TRIP DELUXE

The TRIP DELUXE is the second prototype of the TANDY TRIP rhythm/drone machine. This version has all of the same functionality as the first TRIP, but has 8 additional rhythms that can be selected with the touch-control inputs when the added 'RHYTHMS' switch is set to the 'ALT' position. While the 'RHYTHMS' switch is in the 'HOLD' position, the last ALT-RHYTHM selected will be held, and the touch-control inputs can be used without interrupting the pattern. The ALT-RHYTHMS can be clocked independently of the drum voices' pitch control. This is especially useful when the PITCH is modulated by the sequencer, since the change in pitch of the drum voices will not change the tempo of the rhythm. The ALT-RHYTHMS can be clocked by external clock sources, or by the TOY-RHYTHMS at 1/4, 1/2, 3/4, 1X, 1.5X, 2X, or 3X time. The clock input for the ALT-RHYTHMS is held at averaged input intervals(tap-tempo), so the TOY-RHYTHM tempo can be used to set the ALT-RHYTHM clock, then switched to EXT-CLOCK so that the ALT-RHYTHM clock is independent of the TOY-RHYTHM it was synced to. The DELUXE has 5 volt CV inputs for the two filters, and the pitch. There are 5 volt CV outputs from Sequencer-2, and EG-2. There are also sync outputs from the master-clock, and Sequencer-1 clock, and there is a Clock-sync input jack. All are 0-5 volts(rising).

TRIP

The TRIP project is the second part of the RadioShack Musical Elephant Keyboard(see PAL). 

The TRIP is an experimental drum machine made from a dual-voice drum chip. The drum chip has 8 pre-programmed rhythms. Only the sound chip was used for this mod. The rest of the circuit and enclosure are built from scratch.

FEATURES

-Global Pitch modulation

-8 preprogrammed rhythms with start/stop, and tempo-up/down

-Two drum voices; "TONE" and "NOISE"

-Two independent Envelope generators(one per voice)

-Two independent resonant Filters(one per voice)

-Two independent VCA's(one per voice)

-PT2399 Echo circuit with two independent mix knobs(one per voice)

-Dual 8-step analog Sequencer with reversing clock inputs

-VARI SYNC variable Sequencer Clock

-ARG Attack/Release Generator

-8 Roll/Flam EG trigger inputs

-8 input multi-use capacitive-touch keys

PAL

The PAL project started in early February of 2025, and was finished by mid April. The synthesizer is built around a monophonic keyboard voice chip from a RadioShack "Musical Elephant Keyboard" from the early 90's. Only the sound chip and the keyboard keys were used. The rest of the circuit and enclosure were designed and built from scratch.

FEATURES

-Two octaves of micro-keys

-Voice Waveform/Octave modulation joystick

-LFO Rate/Depth modulation joystick

-Single 12db HP/LP resonant VCF

-Single VCA

-Single Looping Attack/Decay envelope generator

-Pitch modulation knob

-PT2399 Delay

-Master Volume knob

-8 Step Sequencer

CREATOY TRAINS

I found these two on Ebay in early November of 2024. They are somewhat generic looking train keyboards by the brand Creatoy from 1995. Many toys made by Creatoy from this era, and similar toys like them have a special place for me. As a child of the late eighties and early nineties, I would see a lot of these lesser known toys at friends' houses, and school growing up. At the time, it seemed like there was no shortage of these off-brand obnoxious toys everywhere. Now they seem to be harder to find. When I have a little extra cash, I love to scour Ebay for these types of forgotten relics. 

PT100

The Noystoise PT100 is an experimental synthesizer designed and built around the HD61702xx sound chip. The chip can be found in many Casio keyboards from the mid-to-late eighties, including the Casio PT100, hence the name. Beyond the HD61702xx chip itself, the rest of the synthesizer design is completely original.

YAMAHA HS 200 REVISITED

In fall of 2024, the owner of the modified Yamaha HS200 I modified some 10 years ago contacted me to have the keyboard fixed. It was still mostly working, but the pitch range was not able to go up to standard tuning. It was unstable and wouldn't stay in tune. We mutually agreed that it would be best to send it back to me for a repair despite the cost and risk associated with shipping overseas these days. There was really no hurry, and the keyboard eventually made it back around the holidays.