So as I was cruising the motorways of Yorkshire this morning ejoying the quietness because of all the snow we've had for the last few days or so I started thinking about how one might trace the curves. I seem to remeber our Dave doing this a couple of years ago and having a lot of fun.
Presumably I'd need a variable HT, and variable cathode resistor. Set grid bias in 5V intervals and hey presto. Or use a grid bias supply with a 1R resistor in the cathode to measure current?
12GN7 Triode Curves
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#17
Or, a multimeter set up as a milliammeter in series with the cathode.
Yes a variable HT supply, another meter would be useful to monitor the Volts.
Variable grid bias may be done with say a 100k pot and a PP3 battery (or two) but of course that needs measuring as well.
Yes a variable HT supply, another meter would be useful to monitor the Volts.
Variable grid bias may be done with say a 100k pot and a PP3 battery (or two) but of course that needs measuring as well.
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#18
Yes i did our Simon, and it was fun. Nick talked me through it and I plotted (roughly) the curves of a 6EM7.simon wrote: I seem to remember our Dave doing this a couple of years ago and having a lot of fun.
2 x PSU's. 1 HT and 1 LT + 2 meters IIRC.
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#21
Got home yes, but a 'mare all-round. Just under 3 hours each way to get to work, meh.Mike H wrote:You got home alright then?
DTB
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