RK7

Post Modular

£685

Thyratron VCO The RK7 is an 8HP Eurorack version of our legendary TM-3/S-1000/R-55 VCO circuit. The entire circuit is based on two tubes: a 5696 thyratron and a 5702 subminiature pentode, both of which are military surplus tubes used in avionics. The 5696s are still available but getting scarce, and they require a higher plate voltage than our other Euro modules. Like the R-55, the RK7 has a pentode clipping stage which provides voltage control over the gain and clipping level. 5702 subminiature pentodes have always been rare and little used outside military equipment. The RK7 is profoundly we

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Buy from POST MODULAR LIMITEDPOST MODULAR LIMITED is a UK retailer, not the maker. Out of stock. Price seen 2026-09-26. Not an affiliate link, we earn nothing from it.

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UK company
Registered at Companies House as POST MODULAR LIMITED, number 06889917. Checked 2026-08-29.
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RK7

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