0.838% THD at just +/-20V swing isn't that spectacular.
Using the tube at just 30% dissipation is not a good idea in general, that's often the non-linear region of operation.
Using the tube at just 30% dissipation is not a good idea in general, that's often the non-linear region of operation.
I have two tx, one 150VAC 0.2A & the other 250VAC 0.2A. I want to make to increase the 1Vrms of noDac to 2Vrms that's the standard output of DACs.
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OK, put a voltage doubler on the 150V tx to get ~350V. Use a 35K plate load resistor and a 1.4K cathode resistor.
For even better performance, a 300 ohm cathode resistor and a CCS set to 20mA on the same supply would be nice.
For lower voltage operation, a plate choke is a good way to run a lot of current through the tube without having to use a really low value plate loading resistor that screws up THD.
For even better performance, a 300 ohm cathode resistor and a CCS set to 20mA on the same supply would be nice.
For lower voltage operation, a plate choke is a good way to run a lot of current through the tube without having to use a really low value plate loading resistor that screws up THD.
I have a hybrid mu-follower from Ale Moglia that can be set to 20mA🙂. What soud be the B+ before the hybrid mu-follower & what B+ after to the plate?
I look for if I have any 300 ohms for cathode resistor: what's the grid voltage?
Also I have a couple of OPT but I like more the hybrid mu-follower.
Now I have 3.3V battery bias to the grid.
I look for if I have any 300 ohms for cathode resistor: what's the grid voltage?
Also I have a couple of OPT but I like more the hybrid mu-follower.
Now I have 3.3V battery bias to the grid.
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OK, with 400V you could up the plate load resistor a little bit.
You haven't said what you're doing with this, so is 400V a useful B+?
You haven't said what you're doing with this, so is 400V a useful B+?
It's a little bit high, if I remember well I don't have 470uF for this high voltage.
I will use the hybrid mu-follower to set the 20mA CCS.
I will use the hybrid mu-follower to set the 20mA CCS.
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Post a schematic.
The grid will be at DC ground potential.
