We worked a lot with Max and Flo on the Synkie modules at our research week in April, so much that we didn’t take time to blog about it. So here, finally a little roundup of what has happened.
Here’s a ZIP archive witch Eagle and PDF files and of all modules developed so far. But beware: we found a lot of errors only after building these modules, and had to modify them sometimes quite heavily (think of inversed supply traces and such…). We’ve corrected these errors on the circuit schematics, but we have yet to reroute the board files – don’t etch them like this….
This one starts to work really nice.
- A led shows if we have input signal (sync)
- Switchable 75Ohm input terminator
- Input conditioner with switchable gain and AGC.
- Genlock output on front panel
A Maxim MAX7450 at the input conditions our input signal and dc-couples the Backporch to 0V. All synkie signal processing will be done fro now on with the Backporch sitting on 0V. This greatly simplifies all further processing…
We’ve also added a filter to merge the H-sync and Backporch pulses from the LM1881, which eliminates alot of the switch transients we had before.
- See if we’d not use much cheaper output buffer op-amps
- Make outputs short circuit protected!
In our first version of sk02, the Max4310 eventually went up in flames and smoke, just the day before I wanted to present the synkie to the SGMK crew. In this revised version, we added some protection diodes at bot signal inputs. Since then, no more smoke signals.
- All modues should have this kind of input protection!!
- The sk02 module should clip the input signal at 0V and at around 2V.
- A second buffered output would be nice
This module is getting obsolete because
- all alone it doesn’t really serve a purpose
- not enough input impedance
- has tendency to invert the signal at low offsets
- incorporate a real clip (0/2V) in the sk02 resyncer module
- offset should go into VCA module
This is basically just a Maxim MAX7450 signal conditioner with some buttons and connectors soldered to its leads. Kinda obsolete, now that the sk01 module has its own conditioner built in, but this can be a useful module to condition a second source.
Simple utility module. 3 lane 2 way multiplexer, controllable through both CV and switches, built with one good ole 4053.
A voltage controlled video amplifier. First version. Works really well, nice picture.
- Could have more gain, more dynamics
- Needs a CV potentiometer on the front panel
Nothing much to say. A triple LFO for control voltages. Works very well. There’s just not enough of modules to control with it, right now 😉
That’s all for the moment – hopefully we’ll find more time soon to invent more modules…
Modules that would be nice to have:
- Video-Splitter (1 in 4 out)
- Summing Amplifier (4 in 1 out)
- Delay 20ms, 5Mhz