[Milsurplus] RAX 1 Receiver information needed

[Bob Kulow]

Looking for basic information on the RAX 1 receiver from WW2.

> Filament voltage?
>   
28 volts
> AC ok on filaments?

> Mine is rewired for 12 VAC, works fine
>   
> B plus voltage?
>   
Manual shows 135 volts on plate, 153 volts on screen of 12A6.  Screen 
connects directly to dynamotor - no series resistance
> Rear panel power connector pin out?
4 pin P101:
1) Audio out
2) Ground
3) B- (Buss grounded internally - no bias circuit like BC-342)
4) +28 VDC fil & dynamotor

2 pin dynamotor socket:
1) B-
2) B+
> Audio output impedance?
>   
Output tranny turns ratio 5.1:1  Assuming 12A6 Z(plate) is 5k, Z(out) is 
about 520 ohms

Nice receiver.  Mine has AC supply built in back.  Logged many NDBs and 
DX BCB stations with it.

I have preliminary manual, NAVAER 08-5Q-245, reprinted March, 1945 if 
you need more info.

73
Bob WA2UEH