Analogue LFO - minor adjustments - new jacks (PJ321 -> pj324) - remove Sine Adj
555 Based LFO - minor adjustments - new jacks (PJ321 -> pj324) - remove XXX
NAND - Footprint adj
Fix issues with RevA
+/- 10V LFO Square, Triangle, Sine
2 frequency ranges
+/- 10V LFO Square, Triangle, Sine
NOT Gate (pull dn) - NAND Gate (both pull up) - AND Gate (both pull up)
0-10V output - CMOS input
0-10V output - CMOS input
+-10V Input/output - DC couple
Top - 3 input mixer with phase reversal
Bottom - 3 mult output with phase reversal - uses mixer output as input if not applied to mult input
| Stage | Detail | Status |
|---|---|---|
| create material | sch/pcb | OK |
| gerber | OK | |
| production | OK | |
| produced | Yes | |
| delivered | OK |
| Test | Detail | Status |
|---|---|---|
| Initial Inspection | OK | |
| Initial Technical Test | LFO555 | |
| PJ321 should be 1 mm further from the front, center tap works - minor footprint twist in pj324 | ||
| Initial Technical Test | NAND | |
| cut power plane and add 20k across to fix not blowing other units due to hard pull up on tip. | ||
| Initial Product Test | LFO | |
| Initial Product Test | LFO555 | Sine and Tri not working - needs ac coupling from square - needs dc compensation |
| Initial Product Test | MMX2 | |
| Initial Product Test | NAND | Now working with 4093 - needs pull up resistors and I/O protection |
| Initial Product Test | FlipFlop |
| Test | Detail | Status |
|---|---|---|
| Product Test | LFO | |
| Product Test | LFO555 | working right - tri and sine needs tweaking of waveforms |
| Product Test | MMX2 | |
| Product Test | NAND | working - see issues |
| Product Test | FlipFlop | Working as intended except for LED's |
| Quality | LFO | |
| Quality | LFO555 | |
| Quality | MMX2 | |
| Quality | NAND | |
| Quality | FlipFlop | |
| Long Term Product Test | ||
| Power Draw |
Hard pull up to 12 can fry other units !!! Add resistor pull up
Output protection (series resistor?)
AC coupling of Square should be considered - internal and at least DC adj external
bias current compensation (eg. 10k to GND)
Initial Analogue LFO
| Stage | Detail | Status |
|---|---|---|
| create material | sch/pcb | OK |
| gerber | OK | |
| production | OK | |
| produced | Yes | |
| delivered | Yes |
| Test | Detail | Status |
|---|---|---|
| Initial Inspection | OK | |
| Initial Technical Test | LFO555 | 555 and 072 gets warm in certain settings |
| Initial Product Test | LFO | Works well with R311 not mounted |
| Pot's should be 1 mm closer to front (or jacks further back) | ||
| Initial Product Test | LFO555 | Sine and Tri not working - RV101B should have 500R series resistor |
| Initial Product Test | MMX2 | Works nicely |
| Initial Product Test | NAND | Not working with 4093 - footprint matches 74HC00 |
| Initial Product Test | FlipFlop | Working |
| Test | Detail | Status |
|---|---|---|
| Product Test | LFO | |
| Product Test | LFO555 | not working right |
| Product Test | MMX2 | Working as intended |
| Product Test | NAND | Will Never work |
| Product Test | FlipFlop | Working as intended except for LED's |
| Quality | LFO | Sounds nice - a few constraints on pot's would be nice |
| Quality | LFO555 | |
| Quality | MMX2 | |
| Quality | NAND | Will Never work |
| Quality | FlipFlop | |
| Long Term Product Test | ||
| Power Draw |
1 - SW101 too close to P101
1 - 1206 caps (C201+C202) are too close to the switch to mount both
1 - LED positions swapped
Will Never work - Footprint wrong so Input is directly coupled to output for some NAND's
1 - 100k should not be mounted (it ruins feedback)
2 - Sine pot should have 2k series resistor
3 - C303 could be 100nF and 1uF addon with a switch for high low
4 - Frequency pot is sensitive at low freq
5 - Chose different Jacks
6 - Consider adding series resistor to outputs
7 - mounting holes
8 - Pot's should be 1 mm closer to front (or jacks further back)
1 - RV101B should have series resistor (330 - 1k)
2 - All outputs should have a series resistor (470R ?)
3 - Pot's should be 1 mm closer to front (or jacks further back)
4 - RV101 footprint not matching pots
1 - LED positions swapped
Will Never work - Footprint wrong so Input is directly coupled to output for some NAND's
https://www.electronics-tutorials.ws/waveforms/555_oscillator.html
http://electro-music.com/forum/topic-31166.html
