16-06-2013, 07:43 PM
Hello David if there is no green display it usually indicates a failed valve, the usual checks will confirm....
Heaters lit up.
Target anode volts present on valve pin.
Cathode pin connected to HT -Ve.
Triode anode pin voltage present.
If bright green display but no tuning indication....
Triode anode volts present on valve pin (usually via a high resistance source) and varying between no signal and strong signal.
Ditto triode grid.
Dull display normally means a duff valve if heaters/HT etc are present on the pins.
Lawrence.
Heaters lit up.
Target anode volts present on valve pin.
Cathode pin connected to HT -Ve.
Triode anode pin voltage present.
If bright green display but no tuning indication....
Triode anode volts present on valve pin (usually via a high resistance source) and varying between no signal and strong signal.
Ditto triode grid.
Dull display normally means a duff valve if heaters/HT etc are present on the pins.
Lawrence.
