>From: "Vic K2VCO" <[email protected]> >Obviously I haven't tried it (!) but I suspect that the >external magnetic field from a >toroidal transformer is much less extensive than that of the >usual laminated type.
Tom W8JI wrote: >Don't bet on it. :-) > Tom and I discussed this on the AMPS reflector, back in 2007. Flux leakage from a toroidal winding at 50/60Hz is MUCH less of a concern than it is with toroids at RF. The specific question on AMPS was whether two toroidal transformers can be stacked closely together without magnetic interaction, and the answer was: Yes, they can. With two identical toroidal transformers sitting one on top of the other, I connected 230V AC to the primary of one and measured only a few millivolts on the open-circuit primary of the other. That isn't quite the same topic as the flux leakage from a single large transformer, but it's a good indication that leakage can be very low indeed. Obviously the answer will also depend on the quality of design and construction, not only in the transformer but also in the rest of the amplifier, because flux leakage is also affected by the external connecting wires. For the lowest possible flux leakage, it is important to minimize the physical size of the 'coupling loops' created by the connecting wires, especially if the stray magnetic fields can also interact with a steel chassis. -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
