Available as an assembled Module and as a DIY project.
This Module is currently available.
Voltage Processor
The ES14 is a circuit for adding and inverting control voltages. Full processing control of 3 input voltages is provided. A manual offset voltage can be set using [OFFSET] to be added to the other three inputs.
You can use this module as a voltage multiplier. Put your incoming voltage at one of the inputs, then multiple off that input to the next processor input to double it.
Keep in mind that you can use this module with no input voltages. The offset knob is handy for driving one or more modules together as a group, or for using negative bias to VC an oscillator into extra-low territory.
Since several of the EuroSerge modules have no VC processing input, it's handy to have one of these to trim the output of a USG, Random Source, or TRK Pressure into a more subtle range.
[Current draw checked with Elby Designs Jan 2020]
https://www.elby-designs.com/webtek/euro-serge/es14-voltage-processor/es14.htm
These merchants probably sell this module. Huh?