zenith: H500; 5H40

ID: 23192
zenith: H500; 5H40 
23.Mar.04 22:56
2831

Ralf Sürtenich (D)
Beiträge: 31
Anzahl Danke: 12
Ralf Sürtenich

There was in 1953 a 5th edition (Revision D) of H500 with an additional socket for an optional 50A1 voltage regulator tube. In the empty socket was a jumper plug which enables a 1.200 ohm resistor when no 50A1 was used. So with the installed 700 ohm restistor and the additional 1.200 ohm resistor the heater circuit had the same resistance like the standard H500 circuit with 2 * 950 ohm resistors.

It's likely this last H500 edition was a test series for the RR-520 or it were just spare chassis of this which were used in the standard H500 cabinet. But in difference to RR-520 this chassis isn't using tube shields or a shielded RF-head, and it has no dial light.

Für diesen Post bedanken, weil hilfreich und/oder fachlich fundiert.