Power supplies and auxilliary circuits for R-140 amplifier

by Dominique - F1FRV

Rev 3   August 2007

Rev 3a2  March 2014

For more conventional tetrode boards, see Tetrode_Linear_Amp


All drawings are mainly in French... But, i hope, schematic diagrams would be nevertheless understandable by others ...

Revisions takes into account some pertinent comments made by Ukrainian and Russian hams in a CQHAM.RU forum about R-140 amplifiers.

G2 screen voltage application on tube is now delayed of ~1 second after high voltage application, and HV & G2 voltages removed during operation of the motorized tuning components.

A new small circuit is added for "in tuning" & "overload", necessary when R-140 7PSZ antenna tuner is not connected to amplifier.

Nota, the +350/400/450 V circuit uses power Zener diodes available here. This is not the best technical solution, other schemes are easy to find on the web, or here.

The "S" relays used here were very common relays, and found at low cost in Dutch or German ham flea markets. New ones are now very expansive...

"Safety Chain" with relays for RF immunity.

PCB for safety chain

Amplifier by-pass relays supply calculations

Special transformer and chokes

Other supplies circuits

Rectifiers, fuses and -100 V Zener diodes.

Supply panel, G2 current detection and trip

Some pictures of the works....

Click on pictures to enlarge

For now, That's all Fox....

You can download all docs and PCB's files here: Tetrode Supply.zip

For more conventional tetrode boards, see Tetrode_Linear_Amp


Dominique - f1frv@sfr.fr OR

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