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Title: leave it in, take it out, leave it in............... Post by: wb3eii on November 30, 2014, 05:16:10 PM OK, here's the scenario, solid stating the power supply on the mod deck of my t-3.
I'm looking at the easy way, which is to just jump a diode at pins 4 and 6 to pin 8 at all of the 5r4wga sockets. I'm also looking at the harder way, which is lifting the filament wires at the socket and at the transformer. Second method will allow me to take the d.c. voltage off the filament transformer, and possibly save me some grief if the 5 volt transformer ever decides it doesn't like the high voltage running through it. So do I leave the filament transformers in, or take them out? Is there really a need to run my dc voltage out through the center taps? Solid stating this supply is really necessary, as there is a big wire wound pot at he primary of the filament transformer that has a habit of opening up, I found a new pot, I don't want try to find one again.73 Ed. Title: Re: leave it in, take it out, leave it in............... Post by: KA2DZT on November 30, 2014, 05:35:15 PM Disconnect the filament xfmrs but leave them on the chassis. If the dc voltage is above 400 volts you should use two 1KV piv diodes (in series) in each leg.
Fred Title: Re: leave it in, take it out, leave it in............... Post by: steve_qix on November 30, 2014, 05:38:05 PM Yes, disconnect the transformers but might as well leave them in. AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
If it's a full wave center tapped type of configuration, the diodes will need to be 2.8 X the RMS voltage of the transformer (RMS voltage being 1/2 the full secondary voltage - AKA center tap to one side of the secondary). That's the minimum. I'd make it 4x the RMS to be safe. Diodes are real cheap these days. Regards, Steve |