How to make a tubes tester for 6146B / S2001A

You can choosing pair for tubes in TS 830/820
Measurement Current of plate for variable voltage on Grid #1
Also can measure current of filament, what is very important for final unit TS830 (where filament of pair tubes connected in series)

  Second CW filter in 1st IF of TS-830

YK-88C 500Hz and YK-88CN is good filters for 1st IF of TS-830, but we can not use both filters. Why ? I made small board with place for two filters.

 

I re-wired the DH (I did not use digital hold) button for choose the second filter on the board. I can use filter with bandwidth 500 Hz or 270 Hz and check filter with 600 Ohm resistor (impedance of input/output filter).

 

Low insertion loss and big isolation between filters !

I bought YG-455Ñ

I made iambic electronic CW key with universal keying for negative ( in old tranceiver such as TS520 TS530 TS820 TS830) and positive (modern tranceiver). Circuit of key optically isolated to prevent unwanted DC -70V and RF coupling between keys circuits and circuits of transceiver supply. Installation in some type of shielded case is recommended, but the board is quite immune to RF and in many cases will work in an unshielded case for CW drilling without transceiver .

 

 

Installation Instructions

I used potentiometer "VOX Delay" (250k) for Speed control of key and set new potentiometer for "VOX Delay" on back panel.
Shielding the cables for "Speed control" potentiometer on front panel of TS-830 is recommended but may not be required. If you use shielded cable, you can grounded it only in PCB of key. The PCB of key can be set near IF unit or transformer. Jack 3,5 mm and potentiometer "VOX Delay" mounted to back panel. Supply 12 v for CW key got from pin# 12 of AF UNIT (X49-1140-00).

 

Schematic of iambic electronic CW key