Nick wrote:....first most regs are inductive in nature and have rising impedance with frequency, secondly if its a series reg, then its not equally good at sinking current as sourcing it (or the other way for -ve regs), so again the cap will help out with tha.
Ah, got it (I think), the chip will be seen as an inductive reactance XL by the waveform across the secondary of the IT, the cap gives a low Zpath to ground and gets it out the way of the reg chip function yes?
Nick wrote:Regulated bias supplies are not always a good thing. As the mains voltage changes the anode voltage on the valve will change (unless its also regulated), if the grid voltage is unregulated it will vary at the same time and help to keep current constant (ish), regulate the bias and not the anode voltage and that won't happen. Not a big deal with low gm valves, but makes a big difference with something like the 6c33c.
Wow, yeah, I hadn't thought of that. So, combined tracking of both grid and anode supplies keeps the amp bias points more stable as they follow the mains supply fluctuations together as they're not locked to ref voltage like a voltage reg.... but.... if I was to regulate the HT in addition to the grid bias it might not be a problem even with a high gm valve? Both supplies would be locked in regulation and be oblivious (hopefully) to changes in mains voltage.
IslandPink wrote:Dave, I'm ashamed to say I'm not enough of a Gong-head .
This I need to work on!
pre65 wrote:I'm going to get a cheap 0 - 30v dual bench supply for my CV2799 in A2 experiments because my current PSU only goes up to 12v.
Nice one Phil, bench supplies are very very handy. I should maybe treat myself to a dual LT supply @ a good few amps. Instant heater supplies!
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