Available as an assembled Module and as a DIY project.
No info about availability.
Voltage Injecting Mixer
The voltage injecting mixer is a compact fully DC coupled two channel mixer module with the possibility to inject an +/- 8V offset on the incoming voltages.
Channel one has an attenuverter circuit which allows to invert or attenuate the incoming signal. The Attenuverters maximum gain can be set with a resistor on the board (Gain +/- 1 or +/- 2).
Channel two is fed right away into the summing circuit of the module.
If there are no signals connected at the channel inputs the module simply acts as an offset voltage generator.
The final output voltage is displayed by the backlit syringe on the frontpanel. Red indicates positive voltages, green indicates negative voltages.
Tunable Parameters:
ATV (sets the gain of IN1)
OFFSET (adds offset to the outgoing signal)
I/O:
IN1 is the input jack for channel one
IN2 is the input jack for channel two
OUT is the summed output of IN, IN2 and the OFFSET voltage
These merchants probably sell this module. Huh?