Du Mont RA103-D

12" screen, 1949
click on image to enlarge

"The Rumson" is not particularly popular with collectors (this one excepted), who generally prefer the earlier "Chatham" RA103 for its unique doghouse shape.  It's just as heavy!  

This is the mighty impressive continuous tuner.  Down at the far left it starts with TV channel 2 and tunes up through the VHF1 band to channel 6, at which point it changes gear ratio and tunes through the 88-108Mhz FM radio band and keeps going, picking up at channel 7 (there's not much going on between FM and VHF2) all the way through 13.   So what appears to be a bandswitch is, in fact, not.  Marked "F.M., TEL, TEL", it merely kills the CRT in the F.M. position and shuts off the dial lamp in the second TEL position.  Du Mont thought of everything!  Well...everything but a tone control.  :(
Tube Complement
RF amplifier   1    6J6   grounded-grid
oscillator 1 6AB4 
mixer  1 6AK5 
video IF amp  3 6AG5 
video det/DC rest  1 6AL5 
video amplifier  1 6AG7 
1st sync clipper  ½ 6SN7GT 
2nd sync clipper  1 6SJ7 
horizontal sync disc 1 6AL5 
horizontal AFC  1 6AC7 
horizontal osc  1  6K6GT 
horiz discharge ½ 6SN7GT 
horizontal output  1 6BG6G 
damper   1  5V4G 

vert buffer/

vert osc/discharge 

 1 6SN7GT 
vertical output  1 6SN7GT 
audio IF amp  1 6AU6 
FM limiter  1 6AU6 
discriminator  1 6AL5 
audio amplifier  1 6SJ7 
audio output  1  6V6GT 
tuning eye  1 6AL7GT 
time-delay rectifier  1  6AL5 
B+ rectifier  2  5U4G 
bias rectifier  2  6X4 
HV rectifier   1  1B3GT 

©2006-2012 Phoenix Enterprises