Eddy, The 21 kHz spaced between peak probably originates in a switching power supply and the loud "whir-whir-whir" noise may be generated by a motor. The slow movement up and down the frequency may originate from a motor controller changing the motor speed. The precise timing (1230Z on) sounds like its a timer turning on a high efficiency motor.
My guess: one of your neighbors recently installed a high efficiency furnace. I have exactly the same type of RFI originating from a high efficiency heat pump one mile southeast of me. Thankfully its "only" S7 and the Beverages eliminate it except to the southeast. Good luck! 73 Frank W3LPL ---- Original message ---- >Date: Wed, 16 Jan 2013 08:40:27 -0500 >From: Eddy Swynar <[email protected]> >Subject: Topband: RFI / Interfering Phenomenon...? >To: [email protected] > >Hi Guys, > >I wonder if what I've been experiencing here is strictly a local case of RFI, >or if others are hearing it to, especially at stations near southern >"VE3"-land...? > >Specifically, since roughly early December (when I first noticed it), at >precisely 1230Z each day, & at around 1820-KHz, a loud "whir-whir-whir" noise >suddenly starts up that is very raspy & broad...it can be heard at roughly >21-KHz spacings each way, up & down the band, and the entire "progression" >very slowly moves down in frequency... > >It's hard to put into words: imagine the whirring police siren from the film >"Smokey & The Bandit", only with a very raspy / rough tone, and very broad. It >peaks here with my K9AY that's pointing due north, causing me to suspect that >it may well be some automatically timed gizmo that my gadget-crazy neighbour >several hundred feet north of me may have acquired & "...put into >action."...but then again, it could be something else, emanating from >who-knows-where... > >Is anyone else experiencing this right at 1230Z, or am I the sole lucky >winner...? :o) > >My operations on 160 are not especially affected by this, as I usually pack it >in around 1230Z, anyway---still, it HAS piqued my curiosity... > >~73~ de Eddy VE3CUI - VE3XZ >_________________ >Topband Reflector _________________ Topband Reflector
