Yes, that has been my experience, provided that the given current rating was across the full winding to begin with. In using centre tapped full wave rectification, each half of the secondary is given some time to cool while the other side is delivering current. The primary winding only cares how many total VA are being drawn and you won't exceed that with half the voltage and twice the current.
You can get about 175 mA DC with a capacitor input filter, or about 250 mA with a choke input filter (at lower voltage - nothing comes for free).
It is difficult to calculate the ratio of RMS transformer current to DC output, but you can use the table at http://www.hammondmfg.com/pdf/5c007.pdf or get the free program PSU designer form duncanamps.com.
It is difficult to calculate the ratio of RMS transformer current to DC output, but you can use the table at http://www.hammondmfg.com/pdf/5c007.pdf or get the free program PSU designer form duncanamps.com.
Ok. To apply the same idea. Let's say I have a target B+ of 345vdc at about 27ma. I've got a 500vct transformer that's rated for 40ma at that voltage. I could then guess that I'll have an effective 57ma with a full wave rectifier and my 10H 500ohm choke. According to PSU Designer II I should be just a bit under the mark, but close enough.
Example:
500vct/40ma --> UF4007 full wave --> 47uf --> 10H 500ohm --> 120uf --> 27ma current source = ~325v B+
Example:
500vct/40ma --> UF4007 full wave --> 47uf --> 10H 500ohm --> 120uf --> 27ma current source = ~325v B+
Yes, though that will take about 3 minutes to discharge to below 100V. I'd use a smaller value - like 220K/1W, or 150K/2W.
The bleeder is important if you power it up without tubes, or switch it off before they warm up. The normal operating current bleeds the supply faster under normal operation.
The bleeder is important if you power it up without tubes, or switch it off before they warm up. The normal operating current bleeds the supply faster under normal operation.
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