[Boatanchors] Small Transformer Needed

[Glen Zook]

You can use a pair of filament transformers wired "back to back".  That is, connect the filament winding of the first transformer to the filament winding of the second transformer.  Then, use the primary of the second transformer for the high voltage.  If you use a 12.6 VAC center tapped transformer with only half of the secondary going to the 12.6 VAC secondary of the second transformer, you will get half of the voltage applied to the primary of the first transformer on the primary of the second transformer.  When rectified with either a half-wave or full-wave bridge, the voltage will be higher, generally falling into the range needed.

I do this all the time when I need between 120 VDC and 150 VDC.  Of course, to get those voltages, I wire 12.6 VAC to 12.6 VAC.
 
Glen, K9STH


Website:  http://k9sth.com


________________________________
 From: Keith Densmore <ve3gem at gmail.com>
To: boatanchors at mailman.qth.net 
Sent: Tuesday, January 29, 2013 3:11 PM
Subject: [Boatanchors] Small Transformer Needed
 
Greetings,
I am have trouble finding a suitable transformer for a little project here. Maybe your Junque box can save me. I only need about 10 watts power with a standard primary 110 VAC and the  output around 60-80 VAC center tapped or not.

If such a beast is impossible to find I could use a 110 vac input and about 240 volt output and simply reverse the connections.

Please let me know if you can help.