Mad Bean Pedals AQB_MOD 2019 Quick Start Manual

© 2019 madbeanpedals The AQB_MOD is an add-on board to enable modulation on the Aquaboy (DM-2) project. For the 2019 version, I’ve added an optional LED that displays the modulation rate and an additional resistor to prevent the depth control from being too extreme. Controls • RATE: Sets modulation rate from slow to fast. • DEPTH: Sets modulation depth from min to max. • SW: Switches the modulation on and off. Terms of Use: You are free to use purchased AQB_MOD circuit boards for both DIY and small commercial operations. You may not offer AQB_MOD PCBs for resale or as part of a “kit” in a commercial fashion. Peer to peer re-sale is fine, though. Layout &Traces

1/8W R2 220k 2k2 1 Carbon / Metal Film 1/8W R3 220k 4k7 1 Carbon / Metal Film 1/8W R4 220k 47k 1 Carbon / Metal Film 1/8W R5 2k2 220k 5 Carbon / Metal Film 1/8W R6 1k 10n 1 Film / MLCC 16v min. R7 1k 22uF 2 Electrolytic 16v min. R8 220k LED 2 Red, Diffused 3mm R9 47k 1N4001 1 R10 4k7 9203 1 Photocell Caps SW 1 SPDT On/On C1 10n 100kC 1 9mm or 3362p Trimmer C2 22uF 100kB 1 9mm or 3362p Trimmer C3 22uF Diodes D1 LED D2 1N4001 LED LED Photocell LDR1 9203 IC IC1 TL062 Switch SW SPDT Pots RATE 100kC DEPTH 100kB

give you the ability to dial in all kinds of different modulation. But, if you one just one type of modula- tion (say a slow, subtle modulation on longer delays) then trimmers allow you to just “set and forget” without having to drill more holes in your enclosure. 9mm metal shaft potentiometers (100kC, 100kB): http://smallbear-electronics.mybigcommerce.com/alpha-single-gang-9mm-pc-mount/ Bourns 3362p (100k): https://www.mouser.com/ProductDetail/Bourns/3362P-1-104LF?qs=sGAEpiMZZMvygUB3GLcD7l- 39JMs%2F%2F%2FLOs09gVZSzi2c%3D https://www.taydaelectronics.com/potentiometer-variable-resistors/cermet-potentiome- ters/3362p/100k-ohm-trimmer-potentiometer-cermet-1-turn-3362p.html 9203 photocell: http://smallbear-electronics.mybigcommerce.com/photocells-cds-5mm-diameter/ You can also use some of the cheap Tayda ones: https://www.taydaelectronics.com/resistors/photoresistors/photo-conductive-cell-resis- tor-ldr-650nm-radial-ke-10720.html SPDT Mini (On/On): http://smallbear-electronics.mybigcommerce.com/spdt-on-on-mountain-10tc410/ SPDT regular size (On/On): http://smallbear-electronics.mybigcommerce.com/spdt-on-on-short-lever/ Low -profile Electrolytic cap (22uF): http://smallbear-electronics.mybigcommerce.com/electrolytic-radial-low-profile-16v-1-f-100-f/ • For the LEDs, use 3mm, red diffused for both D1 and LED parts. • You can use a TL072 instead of the 062 for the IC. When powered, pin8 of the TL062 should read about 9v, pin4 0v and all other pins will have varying voltage. Bend the legs on your photocell and D1 so that the top of the LED points toward the face of the pho- tocell. You can enclose the LED and Photocell in some heat shrink or tape, but it’s not absolutely required. However, when testing it outside the enclosure put a towel or something over it to block your room lights from interacting with the photocell. This will let you know how well the modulation will work once in the enclosure. Voltages Notes

the Rate setting. Connect the wire from the SPDT to the “M” pad on the Aquaboy. Note 1: in this case, connect pads 2 and 1 of the Depth pot on the AQB_MOD PCB as shown. Note2: you can just leave the external LED off if you do not want the flasher. Experimental: It’s possible to hook up the Mod board without the switch to turn modulation off. To do so wire the Mod pad on the AQB_ MOD PCB directly to the “M” pad on the Aquaboy PCB. Make R9 220k instead of 47k. When you turn the Depth pot all the way down, the modulation should go most of the way off. You may still hear a very slight amount, though. Wiring2 This wiring shows the pots using trimmers. Use this if you only want fixed modulation with the delay. Note1: you can just leave the external LED off if you do not want the flasher.

The AQB_MOD board has to fit under the Aquaboy PCB. Use some 3m foam tape to securely affix it to the enclosure. You could also use velcro!