In a message dated 16/05/05 23:08:10 GMT Daylight Time, [EMAIL PROTECTED] writes:
First, for the ac cord, use a large enough toroid so that you can get a number of turns through it. Try to get them to lay smoothly next to each other, rather than bunching and crossing over each other. You can remove the ac plug for the winding, then install a new one when the windings are done. Reply: ------------------------------------------------------- Like Bob, N6WG I used a large ferrite ring that was sold at a hamfest for use to construct a filter for hi-fi interference and TVI suppression at HF at about US$1.00 each. Through this wound as many turns of 3 conductor AC power cord that would fit laid flat with it's outer sheath removed. Ended up with about 12 turns secured with plastic cable ties. In my case was using this to suppress a noisy PC switched mode supply at HF so added an IEC free socket on the end of the short cable tail. The incoming power was taken through one of the shielded IEC chassis mounting filter with male connector that are available in the market. Mounted the whole lot in a plastic box with an added MOV suppresser to remove spikes mounted at the terminals of the IEC filter. This is only added for the benefit of the PC to prevent spikes causing system crashes. Mounted the box next to the power socket on the PC switch mode PSU to keep any leads short. Works well allowing me to have the PC running at the same time as working HF which was just about impossible before. Purposely suppressed all three conductors including ground which decoupled the PSU case and by default the PC to contain the interference sources. Noted that a commercial power filter for telephone switch use was found to be similar, with all three conductors including the ground lead decoupled with an inductors. Bob, G3VVT _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
