Search found 130 matches

by andrej
13 May 2016, 09:07
Forum: Pimp-My-Cheap-Pedal
Topic: Replacing a Potentiometer by a Tap-Tempo button?
Replies: 2
Views: 2798

Re: Replacing a Potentiometer by a Tap-Tempo button?

It is possible, but it's easier to make a whole new pedal. It also involves non-trivial MCU programming. If you're not a programmer, it's absolutely not worth your time. Tremolos (and phasers, filters) with tap tempo usually have a microcontroller (MCU) generating their LFO, which is usually output ...
by andrej
23 Apr 2016, 08:52
Forum: Parts & Tools Sourcing & Trading
Topic: What stripboards does everyone use and how good is it?
Replies: 9
Views: 6663

Re: What stripboards does everyone use and how good is it?

You should never sell stripboard circuits. I'f you're selling anything under 10 pieces, you're at a loss if you don't sell it at a very high price - you can afford ordering PCBs. If you're selling more than 10 pieces, ordering boards from China is also the way to go - the price is very similar to st...
by andrej
09 Apr 2016, 01:01
Forum: DIY Projects
Topic: Programmable FX Switcher Looper, DIY low cost, using Arduino [documentation]
Replies: 18
Views: 2705

Re: Programmable FX Switcher Looper, DIY low cost, using Ard [documentation]

there's always a (calculable) chance the ADC triggers conversion somewhere during cap charge/discharge cycle, and you get a wrong read. ADC samplerate doesn't affect it.
by andrej
08 Apr 2016, 18:24
Forum: DIY Projects
Topic: Programmable FX Switcher Looper, DIY low cost, using Arduino [documentation]
Replies: 18
Views: 2705

Re: Programmable FX Switcher Looper, DIY low cost, using Ard [documentation]

multiple resistors - one analog pin won't work correctly with a long cable. realistically, the only way to facilitate reliable pedalboard-switcher communication is with 2 microcontrollers communicating with an asynchronous protocol (rs-232, rs-232-over-current-loop-called-midi, rs-422, rs-485). SPI ...
by andrej
13 Feb 2016, 19:06
Forum: Boutique Stompboxes dissected...
Topic: Earthquaker Devices - The Warden [traced]
Replies: 78
Views: 55463

Re: Earthquaker Devices - The Warden [traced]

Now, for something completely different: I love the 125B layout of this pedal! Could someone measure the PCB dimensions and positions of the middle pin of each of those Alpha pots? Just write down the H, W, A-F measures depicted here (the picture represents the pcb): https://dl.dropboxusercontent.co...
by andrej
03 Dec 2015, 19:36
Forum: Measuring & Matching
Topic: Digital multimeters DMM: which one to buy?
Replies: 47
Views: 52530

Re: Multimeter Recommendations

BK Precision 2709Bhas the best quality / features ratio set you can get under $200... And it's only around $100.

Even Dave recommends it:

by andrej
21 Sep 2015, 23:10
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Pedaltrain VOLTO, guts
Replies: 2
Views: 2147

Re: Pedaltrain VOLTO, guts

Yes, yes it is.

And you can have it made by the chinese under any name you want.
by andrej
16 Aug 2015, 16:14
Forum: DIY Projects
Topic: GONICH - a simple (Arduino) digital pedal switcher!
Replies: 144
Views: 21546

Re: GONICH - a simple (Arduino) digital pedal switcher!

Simmed it for ya in Audacity. There will be fades (RC network on the input of the photofet with a 5ms time constant) in and out, and 5 ms of silence for every loop changing state. So, you have: 5ms fadeIn + loops_changed * 5ms + 5ms fadeOut All 10 loops change state (5 + 50 + 5): https://dl.dropboxu...
by andrej
14 Aug 2015, 07:26
Forum: DIY Projects
Topic: GONICH - a simple (Arduino) digital pedal switcher!
Replies: 144
Views: 21546

Re: GONICH - a simple (Arduino) digital pedal switcher!

No, but I will. 1 loop takes 5ms to switch, 10 take 50ms. But that's only the worst case, when every loop changes status. When only several do, it's quicker - 5ms per loop.

With the photofet muting, it should be just fine.
by andrej
13 Aug 2015, 14:09
Forum: DIY Projects
Topic: GONICH - a simple (Arduino) digital pedal switcher!
Replies: 144
Views: 21546

Re: GONICH - a simple (Arduino) digital pedal switcher!

Just a heads-up: You can expect a commercial Gonich soon, with a complete MIDI implementation (including SysEx save and load for all parameters of each patch, and SysEx firmware upgrades), intuitive interface (never-seen-before) and small size, amp channel switching and a/b/y switching, ... I will p...
by andrej
14 Jul 2015, 11:32
Forum: Modern Stompbox Effects (1975 - ...)
Topic: Maxon - PH-350 Rotary Phaser
Replies: 15
Views: 10500

Re: Maxon - PH-350 Rotary Phaser

How hard are these to find?

It's my holy grail of phasing, along with the Red Witch Moon Phase (also untraced).
by andrej
26 May 2015, 00:17
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

yep, it's refactored now. readable and organized.
by andrej
25 May 2015, 23:40
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

Project went gold. It's done - the first working version, at least. You can try it now. It may have bugs I can't simulate, but we won't know until someone makes a buylist and I build a prototype. I hate sourcing parts myself, it's the bane of my existence. It's missing just one feature, and that's r...
by andrej
24 May 2015, 17:18
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

git, as promised.

https://github.com/randrej/BlueWaffle

waveforms-in-a-json parsing completed.
almost done. just the modes/menus remaining!
by andrej
23 May 2015, 12:17
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

I found some time to do another design iteration. The schematic is pretty much final. I had to use an external ADC (SPI based), because I couldn't get the uC to sample audio at a rate above 35KHz when I added input multiplexing (for pots and cv). Multiplexing takes up a lot of cycles, and an externa...
by andrej
16 May 2015, 16:37
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

I meant kHz.

Oh, and I have some exams now, i won't be doing any progress till mid-next week
by andrej
16 May 2015, 11:58
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

I won't be using Arduino code, only pure AVR C code. I will set the ADC subsystem to trigger at 50 (or 60-70Hz). I will then set the ADC-conversion-complete interrupt handling function to read the most significant 8 bits from the ADCH register (that's where ADC reads to) and pretty much do this: POR...
by andrej
15 May 2015, 20:40
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

When I was a kid, I remember disassembling all kinds of electronic devices that had DACs and loads of them had these r-2r networks (yellow slim integrated ones). Serious audio devices, too! There is nothing inherently bad about either the AVR integrated ADCs or R-2R ladders (if they're implemented c...
by andrej
15 May 2015, 16:16
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

I believe we have enough uC speed to do it all in-box. I also believe they're using the ADC to sample the potentiometer, not to alter the poll rate outside of uC. Also, I remember the time people used external oscillators to trigger sampling - my Boss DSD-3 has that kind of setup. Here's the current...
by andrej
15 May 2015, 10:03
Forum: Boutique Stompboxes dissected...
Topic: WMD Geiger Counter - [gut shots]
Replies: 139
Views: 36906

Re: WMD Geiger Counter - [gut shots]

Hah, I realized they don't have to move the digital voltage reference to 2.5V. We do, because AVR ADC works in the 0-5V range. I used a TLC2272 for the input buffer and gainstage, with virtual ground set to 2.5V by TLE2425 precision reference generator. Fixed everyting with the input, now onto outpu...