transistor with a lot of beta

i.e. they are filaments and cathodes both... So ground one end of each filament, and capacitor-couple a square-wave (switched 5V) to the other end. Maybe two or more square waves, different phases, would be best for power supply ripple...

n put

Huh, Is the current listed anywhere on there? I was testing these little CUI buck regulators, fixed output voltage and ~0.5 Amp in a little through hole pac like an LM78XX.

George H.

Huh, nice ripple... but according to DK it's discontinued.

George H.

Sziklai pair?

Cheers

Den mandag den 15. februar 2016 kl. 15.12.04 UTC+1 skrev George Herold:

can put

re

seller says 1.8A, 3A peak if the pictures are to be believed the IC is an MP2307 rated for 3A cont.

-Lasse

OK, there's been other better solutions posted here. But just to finish my poor little thread... my go-to choices for medium-power (TO-126) have been BD139 (NPN) and BD140. Rated 80V, 1.5A. Fairly cheap, 0.11USD and 0.14USD respectively, from Tayda Electronics.

Cheers, RS

All VFDs are direct heated afaik.

I'm not seeing the problem. If all you want is low Vbe with high gain, a sziklai pair gets you that. But why not just run the filaments from a suitable winding to begin with. Or if you must, use a dropper resistor or diode.

If for some odd reason you wanted to put heaters in series, you could if you used relatively high anode V & drove the grids from this via resistors. VFDs should do 90 or 150v happily enough.

NT