EF Johnson Viking Ranger |
This is my E F Johnson Viking Ranger II. Audio modifications or measurements
Wiring oddities: PLATE meter current: I'm not sure why Johnson did this, maybe they had no choice, but the PLATE meter position does not read plate current. In the plate position, the meter actually reads all current to the screen grid clamp tube system, the 6146 screen grid, and any current through SW4A to ground in the TUNE mode. Since R15 is 30Kohms and HV can be 550 volts or so, there is about 20 mA of "false" PA current. That "false" current is reduced under full power RF operation by about 10 mA or so, where the clamp tube is off. The normal operating plate current at full power mostly includes only plate and screen current. Under all other conditions though the plate meter is very misleading. Other than that and RF on the shafts from the tuning capacitor, I have very few issues with the Ranger. It is a great rig so far.
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