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WIGGLING 'LITE' IN GUEST MODE

[BUILD] 100m-ish LFO
MUFF WIGGLER Forum Index -> Music Tech DIY Goto page 1, 2  Next [all]
Author [BUILD] 100m-ish LFO
fitzgreyve
27/09/16 - attached build doc updated

It's a 100m LFO on the outside, but not on the inside hmmm.....

This LFO is intended to replicate the user interface and most of the behaviours of the Roland 100m LFO (as found in the M-140 and M150 modules).
However, the internal circuitry is totally different to the Roland – it’s PIC based, using code derived from the Electric Druid VCLFO9D (used with permission).
Features:
- Exponential response, 1V/Octave, resolution is 32 steps per octave.
- WAVE – sine, triangle, pulse, rising ramp, falling ramp.
The pulse is positive (+5V) only, as 100m.
Other waves are +/- 5V.
- RATE - frequency control – about 3.8 octaves
- RANGE - switch:
H range RATE control gives ≈ 2.5Hz to 26Hz
M range ≈ 0.2Hz to 3.5Hz
L range ≈ 0.05Hz to 0.25Hz
- RATE CV - input with attenuator :
The LFO has an overall 8 octave frequency range.
- DELAY - an external gate signal (can come from Doepfer bus connection) will trigger a fade up of the LFO amplitude.
normalising the CV input socket to the DELAY envelope output allows the LFO rate to speed up as the LFO amplitude increases.
- SYNC - positive sync input (+5V). Resets the LFO. All the waveforms sync to the correct phase as the 100m.
- /10 - divide by 10 switch. Reduces the LFO output.
- Normal and inverted outputs.
- Optional PIC code for a “hidden” noise with sample & hold waveform.

Prototype (production panel is slightly different - the /10 switch and sync input swap posiitions):



Prices:
PCB GBP 8
Panel GBP 14
PIC GBP 3 (programmed and tested)

UK shipping included, international at cost

PCBs and PICS available now, there is a delay for panels.
woodster
I'm interested. Was thinking I need another LFO
StormB
Hi,
Im in for 2PCB and 2Pic´s
Thanks
StormB
Electric Druid
I'm an Electric Druid, and I approved this message!

The additions to my code look great. Particularly like the fade-in/speed-up feature. Very cool.

Tom
Grumskiz
Hi, I'm also interested in one PCB and PIC.
Just wondering: Is the Roland logo on the panels you sell? That might be a bit risky, even for small non-profit runs :S
Reality Checkpoint
Definitely in for one panel/pcb/pic set to add to my crushing backlog!
whoop_john
Interesting and very good work.

I don't understand how the Gin to Dly0 works. Are you reading pin 10 as an input, sensing a gate in and then switching pin 10 to an output, sending a voltage to Dly0 via the PIC?

Any expansion on the operation of this feature would be appreciated.
Synthsense
I'm in for one panel/pcb/pic set please

Cheers! Guinness ftw!
leeski
i'd be interested in panel/pcb/pic, looks good thumbs up
leeski
Ooops double bubble cry Doctorin' the Tardis Doctorin' the Tardis
PWM
The image of your panel is all croped up..
On my iPhone, that is.
Outtatune
That Rate CV In is expecting a Clock or Square signal, right?
whoop_john
Outtatune wrote:
That Rate CV In is expecting a Clock or Square signal, right?

Wrong. Unless you want only a dual speed LFO corresponding to your Clock or Square high and low levels.

Rate CV, as its name implies, is an analogue input expecting a variable control voltage.

It says in the documentation it can take 0v - 8v in but it converts this to 0v - 5v for the PIC to process., VR5 adjusts the 1v/octave response.
sixty_n
interested in one set
fitzgreyve
Quote:
Is the Roland logo on the panels you sell?
- No, those are for my personal use only! Production panels have my logo (see the build doc front page)

Quote:
I don't understand how the Gin to Dly0 works. Are you reading pin 10 as an input, sensing a gate in and then switching pin 10 to an output, sending a voltage to Dly0 via the PIC?
PIC pin10 ("output level") reads the voltage on C7 (the delay envelope) - the leading edge of a gate pulse (Gin) resets this to 0V via Q1, it then charges back up to +5V via VR3 (delay). U4 just buffers the voltage on C7 to provide "DlyO". Pin 10 only reads the voltage - it's never an output.

Quote:
That Rate CV In is expecting a Clock or Square signal, right?
It's a Control voltage input - it's summed with the "rate" pot voltage before being read (as an analogue input) by the PIC.
drip.feed
Hi Mark, I will take 2 complete sets (pcb, panel and pic). Thanks! thumbs up
Dimitree
A bit off topic, but, does anyone knows if the sawtooth/ramp waveform on the original 100m LFO has the same frequency of the other waveforms, or half the frequency (like on some LFOs, since sawtooth is derived from square and triangle)?
fitzgreyve
Dimitree wrote:
A bit off topic, but, does anyone knows if the sawtooth/ramp waveform on the original 100m LFO has the same frequency of the other waveforms, or half the frequency (like on some LFOs, since sawtooth is derived from square and triangle)?


Looking at the Roland book "the synthesizer" ,and the schematic, I would say with a very high degree of confidence "same frequency".
drip.feed
Hi Mark...any progress with these? Guinness ftw!
fitzgreyve
drip.feed wrote:
Hi Mark...any progress with these? Guinness ftw!

Delivery of the panels should be confirmed in the next few days.
drip.feed
fitzgreyve wrote:
drip.feed wrote:
Hi Mark...any progress with these? Guinness ftw!

Delivery of the panels should be confirmed in the next few days.

Lovely. What's the width of the panel, 8hp?
fitzgreyve
drip.feed wrote:
fitzgreyve wrote:
drip.feed wrote:
Hi Mark...any progress with these? Guinness ftw!

Delivery of the panels should be confirmed in the next few days.

Lovely. What's the width of the panel, 8hp?


Yes - 8HP
fitzgreyve
Panels are now in - PM's going out very shortly to those who expressed an interest.


For those waiting for my Polymoog res and VCO driver, I have the panels, but ITEAD are being remiss with the latest PCB delivery - keep watching.
drip.feed
fitzgreyve wrote:
Panels are now in - PM's going out very shortly to those who expressed an interest.

Schwiinnnnnnnnnng! nanners
GryphonP3
I'm in for one full set please.
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