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Holtek HT8955 Datasheet file:   HoltekHT8955.PDF 000021   3/31/101 3:48 pm
Radio Shack sold/sells these chips, which are capable of up to 800msec delay. Somehow, the file seems to have disappeared off the face of the earth, so I scanned my (thank goodness) hardcopy.

Hypertriangular clock for flangers file:   hypertriangleclock.gif 000020   2/22/101 8:00 pm
This circuit and accompanying article appeared in POLYPHONY magazine in the early 80's. It describes a circuit which provides a more pleasing type of sweep for longer sweeps on flangers. If you delete the circuit fragment that provides a clock pulse, the same LFO can be used to provide the same advantage for phasers. Please note that this advantage is pretty much confined to slow sweeps and will do little good for faster sweeps such as are used for chorus effects.

Generalized DOD-style bypass switching file:   dodswitch.gif 000017   2/10/101 3:05 am
This is a brief article and schematic outlining how the fairly standard FET+Flipflop switching works, as it used in a wide variety of DOD stompboxes. The article is by David DiFrancesco, a former engineer at DOD, and is from a 1983 issue of POLYPHONY. The article explains how to extend the arrangement to make a variety of double-throw configurations (e.g., 3PDT), all of which include an indicator LED.

Mono Pitch-to-voltage converter for guitar file:   GuitarP2V.PDF 000016   2/1/101 5:06 am
This is a Robert Penfold project that appeared in Practical Electronics, in 1987. It provides a standard 1v/octave control voltage, and 5v gate output with variable duration, for driving analog synth modules. I have one almost ready to go but still haven't set it up or tested it, so I can't offer a road test comment, however it appears pretty solidly designed. The most exotic components are a CA3046 and CA3140. Virtually everything else is pretty much stock. Requires a +/-12v supply. PLEASE NOTE that due to scanning, scaling, and acrobat conversion, the PC-mask may not be exactly to 1:1 scale. You may have to enlarge or reduce the page a bit. Keep a 14-pin chip of some kind on hand to place against an IC pattern on the PC-mask to determine if the scale is accurate. PLEASE NOTE as well that the PC-mask is for the more traditional forms of PC-etching, and not for Press-N-Peel. The pattern you see in the article is exactly the way it shold look on the copper side. You will have to flip it around for PnP purposes.

Technology of Autowahs file:   Autowah.PDF 000015   2/1/101 4:45 am
This is an updated version of what has been posted on GEO since the late summer. A few of the illustrations are a bit cropped, but no critical info is missing. A number of new sections have been added, which increase its value considerably. I think it's a good read, too.

DEVICE Issue 12 file:   Device1-12.PDF 000014   1/29/101 3:38 am
This was a newsletter for "electronic" guitarists that was published by Craig Anderton and Roger Clay in 1979, and lasted for 12 skinny but deep issues. Lots of useful info and nostalgia inside.

- Review of PAiA "The Drum".
- Tech notes on SAD-1024.
- Specs on MN3010 BBD chip.
- Active guitars.
- Low-noise guitar preamp.
- Cumulative Index for DEVICE.

DEVICE Issue 11 file:   Device1-11.PDF 000013   1/29/101 3:13 am
This was a newsletter for "electronic" guitarists that was published by Craig Anderton and Roger Clay in 1979, and lasted for 12 skinny but deep issues. Lots of useful info and nostalgia inside.

- Review of EH Polyphase.
- Mods for BOSS PH-1 & Small Stone.
- Pedalboards.
- Pluck follower module.
- MN3005 BBD chip specs.

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