Class B modulator current requirement?

[W2PFY]

I think "The Slaber" has a good point. I think this circuit has other merits as well. For example, using it in a supply where one of the transformers is about half the voltage as the other, either for tune up purposes or the so called low power tap. Using the same filter section make it even "more better" It would be great to run a 4CX15000 say at 1000 volts and when you get quermed, you hit the 7,500 volt tap sending a visible magnetic ripple down the power line. You would want the PIV rating of your steering diode at least double of your highest voltage.

[Edward Cain]

   Thanks to all who have commented. This has been a very educational thread for me.

   Frank, thank you for posting the schematic. I can now understand better what you were saying. It is definitely useful info for me. It seems evident to me, however, that one can never get the combined current rating of two transformers with significantly different voltage ratings without overloading the higher voltage transformer. It would be very useful for this application if there were a fairly accurate "rule of thumb" relationship of % voltage sag as a function of % rated load. I would think this would allow a reasonable estimate of how much total current would be available for paralleled transformers of differing voltage.

Ed

[The Slab Bacon]

Ed,
     A rule of thumb would be kinda difficult for this scenario due to the fact that the voltage sag under load would be different from transformer to transformer. It is also proportional to the size of the wire that it is wound with, the core material, and the actual inductance of the windings themselves. I would think you would have to test each and every one and measure the actual voltages and current under load. But doing it this way sure helps you from having things let the smoke out in your face.

[ke7trp]

Good info. I learned alot.  The 6336/500 trans is the big one. Some T3s had different transformers. You can see his in the manual, they are listed.  from memory, its 110 volt primary. Its a beast.  I ran my T3 all night and had a failure when I first put it in service.. I slid the deck out with a friend and we found a bad Rectumfier.  I put in solid state plug ins. The Power trans was cold.   500MA CCA. For that combo of tubes.

c

[W2XR]

Good info. I learned alot.  The 6336/500 trans is the big one. Some T3s had different transformers. You can see his in the manual, they are listed.  from memory, its 110 volt primary. Its a beast.  I ran my T3 all night and had a failure when I first put it in service.. I slid the deck out with a friend and we found a bad Rectumfier.  I put in solid state plug ins. The Power trans was cold.   500MA CCA. For that combo of tubes.

c

Clark, the Industrial Transformer Corp.-built T-368 6336 VAC CT at 500 MA plate tranny I had in my older single 4-400A rig had a 120/240 VAC primary. I ran that xfmr on 240 VAC.

73,

Bruce