Mike, when you say a 5A current is needed, do you then mean that this pulse is taken in the form of energy stored in C2a & C2b and then current limited by R6? If this is so wouldn't it be possible to put R6 in series with C2a & C2b like it is usually done in a self quenching circuit for cold cathode trigger tubes, instead of in the path of the pulse network for the dekatron? I am not saying that you are wrong, merely curious and trying to learn more!
Did you test the circuit without grounding pin 5 on the 0A5? /Martin On 15 Dec, 07:51, threeneurons <[email protected]> wrote: > Here's a video of a dekatron spinner that's based around a 0A5 cold > cathode gas trigger: > > http://www.dailymotion.com/video/xmzo1p_0a5-relax-osc-dekatron-spinne... > > Other variable speed spinners need a transistor, or triode, to boost > the pulse from the neon bulb relax oscillator. The 0A5 is used in > place of the neon bulb, but this tube generates a pulse so large, that > no amplification is needed. Actually, the pulse is too big. In this > circuit, its 400V, and peaks at 5 amps (for ~2uS). The pulse is > attenuated before kicking the guides of the dekatron. That pulse > destroyed 2 4.7 ohm resistors. The tube works on the 'arcing' mode of > gas discharge, and 5 amps is the minimum current for proper function. > The 4.7 ohm resistor limits the current, and stretches the pulse. Peak > power is over 100 watts, but only for a short 2uS. The original carbon > film resistor has been be replaced by a wirewound resistor. -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
