[TowerTalk] NR-1 noise reduction unit.

[j_stein]

There is a caution about the keying line such as PTT line being free of DC offset and RF otherwise in transit mode the NR-1 could be damaged.... suggestion is for using a optocopter or buffer from the transceiver to the unit such as used with a linear amplifier.... perhaps a separate receiving antenna and a TR switch would negate the need for an optocoupler or buffer device.... I received mine last June and am still fooling around with it as it is very finicky and seems to also attenuate the desired signals.... the main problem at my home QTH appears to be either LED Street lighting or EV charging.... at the cabin I suffered High Line noise after a utility upgrade of the overhead distribution lines.... After some research I purchased a Yaesu FT-710 AESS and the noise reduction features in that transceiver completely took care of the problem... with 100 Watts and my Delta Loop Apex up at 20 ft amongst many pine trees, during the WWDX contest, I worked China, Thailand, and Guam among othersJoeW6AXHSent from my Galaxy
-------- Original message --------From: JP <jp at ezoom.net> Date: 11/13/25  1:37 PM  (GMT-08:00) To: towertalk <TowerTalk at contesting.com> Subject: Re: [TowerTalk] NR-1 noise reduction unit. Yes, it works great under those conditions. Unlike the internal noise blanker in a transceiver, there’s no distortion or noise or other artifacts introduced on a crowded band. We used it during CQWW SSB at KP4AA any time we were running USA or listening for JA/HL over the states. That’s the real trick, it works great when presented with a source of pulse noise, like line noise, and doesn’t degrade the signals at all. J.P. W2XX> On Nov 13, 2025, at 12:26 PM, Richard Karlquist <richard at karlquist.com> wrote:> > So IMHO, the unit should be called a "noise blanker".> > My ancient FT-1000 had a noise blanker that worked very well ... unless> there were other radio signals on nearly frequencies.  Think:  contests.> In that case, it predictably folded like a lawn chair.  Has anyone> tried one of these during a contest?  I would be very surprised if it> would work under those conditions.> > ---> Rick Karlquist> N6RK> >> On 2025-11-12 05:17, Rob Atkinson wrote:>> >> It's an interesting box; wish the manual included a schematic drawing.>> They make sure that you realize it's only good for impulse noise, so>> if that's all you ever have to deal with then okay fine.  In my>> environment, I've had to deal with leaky cable noise (sounds like>> white noise), and continually shifting plasma TV noise among other>> nuisances, so the old phase shifting and nulling networks using a>> noise pickup antenna are necessary here.  But if all I ever dealt with>> were AC line noise and motor ignition noise for example, this might be>> pretty good.   It might be useful for mobile operating.>> >> 73>> >> Rob>> K5UJ>> >> _______________________________________________>> >> _______________________________________________>> TowerTalk mailing list>> TowerTalk at contesting.com>> http://lists.contesting.com/mailman/listinfo/towertalk> _______________________________________________> > > > _______________________________________________> TowerTalk mailing list> TowerTalk at contesting.com> http://lists.contesting.com/mailman/listinfo/towertalk______________________________________________________________________________________________TowerTalk mailing listTowerTalk at contesting.comhttp://lists.contesting.com/mailman/listinfo/towertalk