Friday, 9 November 2018

MaRF - build pics - 248r - rev 1

These are not build notes ... just some pics to help trouble shoot.

The Buchla MARF - Multiple Arbitary Function Generator is one of the rarest of Buchla modules.
I would love to find a real one (or even see one for that matter).
This modern version is the closest I have come to one.


Its a great module. This is Roman's rev 1 of the 248r.



Firmware updates
















these are some pics of the roman build MARF




A post shared by jono (@dj_jondent) on
Some videos of how it should work




A post shared by jono (@dj_jondent) on
internal stage addressing

Wednesday, 7 November 2018

Inside a Korg PS 3100

A friend requested some pics from my Korg PS 3100 the other day so I opened her up.
There aren't too many images of the insides this baby.




 We decided not to remove any cards from the cage.
The synth is working perfectly and we didn't want to disturb anything.






LZX 010 Clock VCO - Castle Video synth

The 010 Clock VCO is a square wave Voltage Controlled Oscillator with a linear response to CV.
It can be used as a clock source for modules such as the Shift Register and Counter.
You can switch between Horizontal and Vertical square waveforms
It looks like there are also high & low frequency ranges.
It might be useful to have more than one of these modules in your system.
This VCO is the 3rd module in the series and is in Eurorack format.

+12V Current Consumption: 9mA
-12V Current Consumption: 7mA
No +5V

It's 4HP and all through hole.
It doesn't require the 14 pin sync cable however the Vertical sync & Horizontal sync signals
enter the module via the power bus.
So you definitely need to use a 16pin power header.

This can be used with vidiot but as the Castle Clock VCO needs sync in the power bus  you'll need a sync generator (Cadet Sync Generator or V cortex) for that one.
Or you can sync from the front panel jack.

"It's a square wave vco, essentially. Prime for clocking logic". (Philip)


 tHE CD4046 - a phase locked loop vco

The 4046 is the core component. Its a PLL vco.
Totally different approach to the Cadet ramps & Cadet VCO

Ignore my placement of a 10 pin power header in the above pic. Use a 16 pin please.
Got tired of waiting on the jacks.
Decided to try the standard ones instead.






 ICs and impt components used:
CD4046BE ------- Phase Locked Loops - PLL PLL w/ VCO
LM6172IN/NOPB ---- Operational Amplifiers - Op Amps Dual High Speed,Low Pwr Amp
2N3904BU -------- Bipolar Transistors - BJT NPN Transistor General Purpose

LZX - Castle
Introduction
00_000 ADC - Analog to digital converter
01_001 DAC - Digital to Analog converter
02_010 Clock VCO
03_011 Shift Register
04_100 Multi Gate
05_101 Quad Gate
06_110 Counter
07_111 Flip flops

Links
+ ADC overview - LZX
+ LZX industries
+ Hackaday - the 4046 PLL VCO
+ CMOS
----------------------------------------------------------------------
Video Index page

LZX Castle Video Synth - 001 DAC

Some build pics of the 2nd module in the Castle series.
The 001 DAC - Digital to analog converter.
This module is in Eurorack format.
iT'S 4HP and all through hole.

 The 001 MODULE is a Digital to Analog Converter. It's a dual module to convert two 3-Bit data streams into two Analog approximations.

Think of it as a pair of summing mixers.
In audio, a summing mixer turns multitracks into stereo.

"The DAC can take the 3 bits from the adc (or anywhere else) and recombine them as an 8 level single stream output. Think of it kind of like a mixer, but it has preset levels for D0, D1, and D2." (Philip)

With the DAC, the data streams are mixed to make an analog signal with the MSB (most significant bit) having the most amplitude and the LSB (least significant bit) having the least. "Pair it with the ADC to produce a solarize effect counter to synthesize waveforms"







a 10 pin power header is needed



LZX - Castle
Introduction
00_000 ADC - Analog to digital converter
01_001 DAC - Digital to Analog converter
02_010 Clock VCO
03_011 Shift Register
04_100 Multi Gate
05_101 Quad Gate
06_110 Counter
07_111 Flip flops

Links
+ ADC overview - LZX
+ LZX industries
+ CMOS
----------------------------------------------------------------------
Video Index page

LZX Castle Video Synthesizer - 000 ADC


Some build pics of the first module in the Castle series.
This module is in Eurorack format.
iT'S 4HP and all through hole.
Quite an easy build

I must thank the entire team from LZX  and Philip Baljeu for making this DIY system possible.
Building these modules from scratch is a great way to learn.
 tHESE are not official build pics and I am in no way affiliated with LZX.

 The Castle 000 ADC is an Analog to Digital Converter. It's used to change an analog input signal in to a 3-Bit data stream.  You will see on the module a single input on the top and 3 outputs below, labelled D0, D1, D2.

"The ADC will take an analog signal and split it into 3 bits or zones, the separate outputs kind of look like a square wave version of staircase, the first output D0 has 4 lines, d1 has 2, and D2 has 1".
 (facebook post from Philip)


The main IC is the SN74HC148N
The SN74HC148  features priority decoding of the  inputs  to  ensure  that  only  the  highest-order data
line is encoded. These devices encode eight data   lines   to   3-line   (4-2-1)   binary   (octal).

The SN74HC148 features ‘priority encoding’ where, if more than one input is active at the same time, the output will select only the most significant active input.

The internal logic is shown below:





The voltage regulators

tHIS is the underside of the voltage regulators. Be careful not to short circuit.


 tHERE  are six LM6172s


Finally done.

Troubleshooting:
There appears to be a sweet spot when adjusting the Bias & Gain knobs.
I'm not sure if this is normal behavior. Outside this narrow range the output signal disappears.
The schematics indicate that the Bias/gain 10K pots effect the first 6172 op amp.

Possibly tweaking the value of those 10k pots or the associated resistors might give a better outcome ??????
I received an email from my friend, Chris who directed me to some info regarding this:
"The bias range is pretty wide, maybe too wide. I wanted enough range to mess with many signals, not just 1V. The controls aren't really something I see people changing a lot, more of just to get the settings right in to the ADC and set and forget. But if people think the range is unusable I can look in to limiting it. In the meantime, anyone who wants to try for themselves, R10 would be the thing to change. its 4.99K right now.” (Philip B).

The Gain control on the ADC goes from non-inverted on the left through zero to inverted on the right. 


LZX - Castle
Introduction
00_000 ADC - Analog to digital converter
01_001 DAC - Digital to Analog converter
02_010 Clock VCO
03_011 Shift Register
04_100 Multi Gate
05_101 Quad Gate
06_110 Counter
07_111 Flip flops

Links
+ ADC overview - LZX
+ LZX industries 
+ Bit numbering
+ CMOS
----------------------------------------------------------------------
Video Index page