If you have a uTracer you could trace a set of curves with the two different heater voltages, keeping to the two extremes of the voltage @ 300mA and 6.3V. Keep the anode voltage as stated in operating characteristics, sweep the grid from cutoff to zero, and capture both sides by measuring the other side with the screen (g2) measurement, and tie the grids together.
It will be easier to visualise the effect than the just the single point on the curve as seen on the oscilloscope.
Ra looks to be high and current low in the quickest view, pointing to a tired tube?
It will be easier to visualise the effect than the just the single point on the curve as seen on the oscilloscope.
Ra looks to be high and current low in the quickest view, pointing to a tired tube?
What is not understandable is why to bear heavy currents from socket to socket and not keeping the heavy currents away using separate leads with necessary currents for each only ? This is what I do, as simple as can be without no wiring complication:
The whole method I used to do a simple straight 'T' wire conection and keep the heavy currents rail away here: https://music-electronics-forum.com...amps/build-your-amp/979103-soldering-question
The whole method I used to do a simple straight 'T' wire conection and keep the heavy currents rail away here: https://music-electronics-forum.com...amps/build-your-amp/979103-soldering-question
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All I do with AC filament wires is twist the two wires together in a variable speed drill. Twisting the wires provides some shielding.
Regarding HT tube rectification, is there a preferred wiring method. I gather that at high voltage electrostatic dominates, and at high current it is electromagnetic, but in either case the twisting cancels it out.
Running HT cables close to the chassis or twisting them seems like asking for trouble so would it be better to use something like coax cable? Will be cancellation effect work on the rectified voltage going to the choke/capacitor?
For the filament (or heater tied to cathode) cable, I gather it should be okay to twist the cables but there will need to be sufficient isolation to the chassis.
Running HT cables close to the chassis or twisting them seems like asking for trouble so would it be better to use something like coax cable? Will be cancellation effect work on the rectified voltage going to the choke/capacitor?
For the filament (or heater tied to cathode) cable, I gather it should be okay to twist the cables but there will need to be sufficient isolation to the chassis.
Isn't earth commonality from input to output?
If so, hot wire, must be corridored esp beyond 450dc
you see how it's done using centering manes & isolators porcelain, identical scenarios, linesmen grooming the high voltage utility power lines
If so, hot wire, must be corridored esp beyond 450dc
you see how it's done using centering manes & isolators porcelain, identical scenarios, linesmen grooming the high voltage utility power lines
Just use wire with the right voltage rating. Read the specs and choose the right type for your purpose. Think not only about the voltage (safety) but also about the current (heat / loss).
Regards, Gerrit
Regards, Gerrit