Hi everyone, I am building the power supply for a preamplifier, I have a telefunken valve rgn1054 mesh, I like it too much when it turns on, and I would like to use it, I would like to filter and straighten the voltage and then enter 2 salas hv2 shunts, I will use a filter clc, with the first 20uF capacitor, a 10H coche, and the second 100uf or more condenser. Is it better to use film capacitors on the second capacitor or an electrolytic? 100uF could be enough for the raw DC for the salas shunt? place the simulations with the various capacitors.
100uf condenser film is quite easy and cheap but 220uf becomes large and expensive, that hump at power-up could cause a malfunction?
100uf condenser film is quite easy and cheap but 220uf becomes large and expensive, that hump at power-up could cause a malfunction?
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RGN1054: max 2x 350V, max 12uF, max 120mA. For such an ancient rectifier it is wise to lower the currents on it. You could insert a resistor, like I did in the enclosed example.
Film capacitors are usefull when they are audible, for instance in a cathode bypass. For eating PS ripple elektrolytes are fine, your shunt will leave nothing behind to worry about.
Film capacitors are usefull when they are audible, for instance in a cathode bypass. For eating PS ripple elektrolytes are fine, your shunt will leave nothing behind to worry about.
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What is the function of the resistor? here are the features of the valve
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Thermionic rectifiers allow for a certain maximal current. That is not only the DC the circuit uses but also the AC ripple because of the reservoir capacitor. Imagine you would place a 220uF right after the rectifier, the rectifier would have a short life because of the large rectifying currents drawn.
There's no need to go as high as 100R, experiment with some values and see what it does to the output voltage. Also, allow for a step load (10% would be enough) and see if you are happy with the output.
There's no need to go as high as 100R, experiment with some values and see what it does to the output voltage. Also, allow for a step load (10% would be enough) and see if you are happy with the output.
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I see,
the ipkr of the rgn1054 should be according to what psud 2A tells me, so the capacitor after the L, could be of a high value, so as to have a gradual voltage increase in output, is it correct?
What you don't want is a ringing power supply. Observe the line when you have altered component values and see if it settles quickly after a current peak. A "wobbeling" line indicates marginal stability. Resistance in the PS is not a bad thing here because you let the regulator deal with transients. 100uF should be enough for the current because your pre amplifier pulls nearly constant current. In case of a PP penthode amp I would up the last cap to 220uF to be sure the regulator never drops out of voltage. You can check with Salas if my reasoning is valid as I have no experience with this MK2 shunt (only with MK1). Send him my best 
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