Drip Electronics 670 Fairchild Compressor Clone Custom Built

Drip Electronics PCB V.1

Tat Parusha case

Sowter and Hammond Transformers

EH and JJ Tubes

Mogami Wiring

There are several important notes from the builders for the customer:

"Zero" trimmer behind front panel does not adjust the meter zero. It adjusts the 6386 tube bias, and should only be adjusted by a qualified technician, as damage to the tubes can result from improper setting.

Meter select switch does not select "In" "GR" "Out". It selects "Balance lo" "GR" "Balance hi". Balance should be adjusted for the same reading on lo and hi positions.

Switches and adjustment trimmers have been installed to have normal metering.

There is no "Ratio" control, it is the DC threshold.

"Left/Right" "Lat/Vert" switch is not wired. This is because
a. you will probably not ever use the "Lat/Vert" setting (for cutting vinyl discs), and
b. the extra wiring increases noise. Hardwiring to the dual mono configuration is the best performance recommendation (DRIP).

Tubes tend to "break-in" over time, it would be a good idea to check the -6.2V bias and regulated 240V settings periodically. Hum and distortion will likely be caused by improper settings, or a bad tube. In that case, turn the unit off immediately, (to avoid further damage), and have the unit serviced. In case of failure, never install a higher rated fuse.

At extreme settings, the output will "thump", as it can be adjusted beyond the useful range. This is normal operation (DRIP).