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wa8yxm · 07-07-2009, 10:49 AM

Incandesent's causing noise.. That is strange.

LED's do, create RFI by the way, if not properly filtered, (those things generate noise dang near "From DC to Light" as the saying goes, in fact, the light they generate *IS* RFI., However sometimes that is what we want. True white noise generators.. Just not much of it, and thus you don't hear it in the radio.

I once made a tune up aid.. Consisted of a near-square wave generator feeding a diode... Genuine white noise with a 1,000 cycle per second on/off rate, Other than frequency you could tweak coils for maximum BEEP and your signal to noise ratio was... Also peaked.

The last step in tuning (Frequency) required other test gear.

07-07-2009, 10:49 AM	#10
wa8yxm Senior Member Join Date: Nov 2007 Location: Mobile, on the road Posts: 1,139	Incandesent's causing noise.. That is strange. LED's do, create RFI by the way, if not properly filtered, (those things generate noise dang near "From DC to Light" as the saying goes, in fact, the light they generate IS RFI., However sometimes that is what we want. True white noise generators.. Just not much of it, and thus you don't hear it in the radio. I once made a tune up aid.. Consisted of a near-square wave generator feeding a diode... Genuine white noise with a 1,000 cycle per second on/off rate, Other than frequency you could tweak coils for maximum BEEP and your signal to noise ratio was... Also peaked. The last step in tuning (Frequency) required other test gear.