Hi Ray

My RMU had two of the three 800 Hz transformers missing.    Since I will be running my TBW off of 120 VAC I decided to get rid of all remaining 800 Hz related parts and wiring.    This resulted in the bottom deck being completely devoid of parts and the middle deck almost free of parts.   The middle deck still has R-219 which is still needed but can easily be relocated.   I've attached two photos.

I plan to mount all new transformers (except the 2 KV supply) onto the bottom two decks of the RMU.    This will be the 500V supply as well as the 2.5V, 10V, and 12.5V Filament transformers.

At present, I plan to have all primaries go through the Filament Rheostat control.

The two 837's require 12.6V for the filament but they are fed by an 18.6 VCT secondary off of  the non-existant T-202.  I think this increased voltage was needed due to the voltage drop in L-302 and L-303 in the Oscillator filament circuit.    I think this then required dropping resistor R-213 in the filament circuit of the Intermediate Amplifier.   I plan on bypassing (shorting) L-302, L-303, and R-213 so that I can use a standard 12.6V transformer for the two 837's.

The 2 KV supply will be external to the RMU and will be fed in via a new plug on the bottom of the RMU, then to S-208C.     The new 500V supply will feed S-208B.

What I still haven't figured out yet is what voltage the 803 suppressor needs on Phone.   This voltage is developed from the non-existant T-203 HV secondary CT via the bias adjustment pot R-205.  There is nothing in the manual about adjusting R-205 (or maybe I'm not seeing it....).  Looking at the 803 data sheet,  for 2 KV plate voltage in Suppressor Modulated Class C phone operation, I'd need about -110V on the suppressor.     Still not sure of this area yet,  but I should have room for a bias supply in the RMU.   The bias supply would feed into the ungrounded end of R-205 then to the 803 via S-209A in Phone operation.

The front panel AC ON/OFF and DC ON/OFF switches will be used as intended.    Both required a good bath in DeOxit for them to work  (Well, they are 85 years old.....)

I plan to repurpose some of the 4 front panel AC Compensation SPST switches.  

One will be for a  “TX/RX” switch for lack of a better term.   In TX, relay K-301 in the HF transmitter will close as it's supposed to do.    Except.....   I plan to ground the Oscillator with a new modern relay instead of K-301B.    That new relay will be controlled by the key or mic switch from the RMU.

When receiving, the 2KV and 500V power supplies will still be providing voltages to the 803, but the oscillator will not be enabled.   I was discussing this with Howie and we feel this is OK as long as plate dissipation is not exceeded, and that concern may require me to run less than 2KV on the plates.

I ran a TBW-5 for a few years with 1200V on the plate and that gave me more than 100W output on CW which is adequate for my needs.     Running phone with the TBW will be a new experience for me.

Any and all comments welcomed.