[Amps] Choke-input with voltage doubler?

[John Popelish]

Jim Kearman wrote:
> From: Steve Thompson <g8gsq at eltac.co.uk>
> 
>>I've also been 
>>burned (both metaphorically and literally) by attractive looking big 
>>transformers which turn out to have been designed for use with choke 
>>input. Hook them onto a capacitor input PSU, and you get much less power 
>>than you were expecting, lousy regulation, and the smell of burning 
>>insulation.
> 
> 
> My friend obtained a 1000-VCT brute of a transformer, weighs 25 lb. Old Chicago Transformer, potted, looks mil-surplus. I assume it was made for a choke-input filter. He wants to use the full secondary with a full-wave voltage doubler. This will be for a linear that will be used for continuous-carrier DSB AM. Looks as though two chokes would be required? Thanks.

If you derate the transformer for output current, the chokes are not 
necessary.  You can also lower the peak factor on the windings by 
adding a small inductance in series with the primary to spread out the 
rectifier conduction time.