Re: [Elecraft] Question from a newbie
http://www.qsl.net/ve3mcf/elecraft_reflect/KNB2_Notes.txt http://www.ac6rm.net/mailarchive/html/elecraft-list/2001-11/msg00530.html Hope this helps. Bored stiff? Loosen up... Download and play hundreds of games for free on Yahoo! Games. http://games.yahoo.com/games/front ___ 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
Re: [Elecraft] Question from a newbie
Pete It all depends on the type of noise you experience. For some kinds of noise, the KNB2 works like magic. For other kinds, it has no effect at all. For some odd noises, it sort of works. Ultimately, it's a crap shoot. It is an inexpensive option, and I would add it as insurance for those times when it does work. I have it in both my K2s. 73, Bob N6WG - Original Message - From: "B Peter Treml" <[EMAIL PROTECTED]> To: Sent: Saturday, March 10, 2007 4:44 PM Subject: [Elecraft] Question from a newbie > I have come into possession of a K2/100 with the DSP filter (KDSP2) but does > not have the noise blanker (KNB2). > Question: (1) Is the noise blanker a worthwhile purchase? > Any thoughts would be appreciated. > 73, Pete-K8PT > > > > B. Peter Treml [EMAIL PROTECTED] > 725 W. Magnetic St. www.qrz.com/k8pt > Marquette, Mi. 49855 > USA > > ___ > 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 ___ 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
Re: [Elecraft] Question from a newbie
I have a K2 with DSP, and just last weekend added the KNB2 to the mix. So far, for the noise I have here, the DSP denoiser works much better than the KNB2. I've just been switching it in and out to see what affect it has, and so far haven't found much noise that it removes. I'm in a relatively quiet place though, so that might be it. As Bob said, it's cheap, and it's a kit you can build and install in about an hour or two, so why not!? :) 73, Jeff N6GQ On 3/10/07, Bob Tellefsen <[EMAIL PROTECTED]> wrote: Pete It all depends on the type of noise you experience. For some kinds of noise, the KNB2 works like magic. For other kinds, it has no effect at all. For some odd noises, it sort of works. Ultimately, it's a crap shoot. It is an inexpensive option, and I would add it as insurance for those times when it does work. I have it in both my K2s. 73, Bob N6WG - Original Message - From: "B Peter Treml" <[EMAIL PROTECTED]> To: Sent: Saturday, March 10, 2007 4:44 PM Subject: [Elecraft] Question from a newbie > I have come into possession of a K2/100 with the DSP filter (KDSP2) but does > not have the noise blanker (KNB2). > Question: (1) Is the noise blanker a worthwhile purchase? > Any thoughts would be appreciated. > 73, Pete-K8PT > > > > B. Peter Treml [EMAIL PROTECTED] > 725 W. Magnetic St. www.qrz.com/k8pt > Marquette, Mi. 49855 > USA > > ___ > 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 ___ 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 ___ 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
RE: [Elecraft] Question from a newbie
I have had two K2's fully loaded. One with a 38xx serial and the other with a 44xx serial. Mine have never left the desk and I have yet to find any type of noise artificial or other that the NB works on. It's fun to build but in my opinion if you are looking for bang for the buck, that's not it. 73, Rich Kd0zv -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jeff Kinzli N6GQ Sent: Saturday, March 10, 2007 7:22 PM To: Elecraft Mail Posting Subject: Re: [Elecraft] Question from a newbie I have a K2 with DSP, and just last weekend added the KNB2 to the mix. So far, for the noise I have here, the DSP denoiser works much better than the KNB2. I've just been switching it in and out to see what affect it has, and so far haven't found much noise that it removes. I'm in a relatively quiet place though, so that might be it. As Bob said, it's cheap, and it's a kit you can build and install in about an hour or two, so why not!? :) 73, Jeff N6GQ On 3/10/07, Bob Tellefsen <[EMAIL PROTECTED]> wrote: > Pete > It all depends on the type of noise you experience. > For some kinds of noise, the KNB2 works like magic. > For other kinds, it has no effect at all. For some odd > noises, it sort of works. > Ultimately, it's a crap shoot. It is an inexpensive option, > and I would add it as insurance for those times when > it does work. I have it in both my K2s. > 73, Bob N6WG > > - Original Message - > From: "B Peter Treml" <[EMAIL PROTECTED]> > To: > Sent: Saturday, March 10, 2007 4:44 PM > Subject: [Elecraft] Question from a newbie > > > > I have come into possession of a K2/100 with the DSP filter (KDSP2) but > does > > not have the noise blanker (KNB2). > > Question: (1) Is the noise blanker a worthwhile purchase? > > Any thoughts would be appreciated. > > 73, Pete-K8PT > > > > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> > > B. Peter Treml [EMAIL PROTECTED] > > 725 W. Magnetic St. www.qrz.com/k8pt > > Marquette, Mi. 49855 > > USA > > > > ___ > > 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 > > ___ > 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 > ___ 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 ___ 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
RE: [Elecraft] Question from a newbie
I built my K2 #54xx in May 06. Built the KNB2 Noise Blanker. Then found it never really seemed to work on any noise! One day, 4 cement trucks & 2 large pickups sat like 30 feet from my shack - all running, all working. The KNB2 did nothing to remove any of that man-made noise. Also it doesn't work on any band noise - that I ever found. I even got a 2nd KNB2, from Elecraft - and it didn't work either? The K2 itself - after build - operated true to all specs, calibrations, & alignments beautifully. I've since felt, the KNB2 is a design job left to be re-done, by some Elecraft designer, when they get around to it. The IC-7000's Noise Reduction and Noise Blanker circuitry - amazingly almost always reduces most band noises, real or imaginary, dramatically. Maybe in the K3? Fred N3CSY 8:00? 8:25? 8:40? Find a flick in no time with the Yahoo! Search movie showtime shortcut. http://tools.search.yahoo.com/shortcuts/#news ___ 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
Re: [Elecraft] Question from a newbie
Hi Pete: I'm always the 'late' one to reply it seems... The KNB2 is a very good blanker... on CERTAIN noise types... but, as with virtually blankers, you DO have to have the right type of noise. It's generally very good no line noise, sparkplug/elec. mixer/elec. fencer noises as well. If you're interested, download http://www.n0ss.net/knb2_demo.zip from my web site and take a listen to my KNB2 in action. This was NOT a 'set-up' demonstration, I just happened to tune across a 20M signal one day when my line noise was pretty much out of sight, turned the KNB2 on, and the noise disappeared... figgered it was a good demo, so I recorded a bit of it. I have to say as well that there WILL be times when the KNB2 will appear to do NOTHING, even though I feel it should be doing its job on some noise I'm hearing. Though I've not 'scoped out' the noise, it's apparent that it must have some characteristic that the KNB2 doesn't like, or can't cope with, so the noise remains... but in general, the KNB2 works very well... FOR ME anyway! 73, Tom HammondN0SS At 07:44 PM 3/10/2007, you wrote: I have come into possession of a K2/100 with the DSP filter (KDSP2) but does not have the noise blanker (KNB2). Question: (1) Is the noise blanker a worthwhile purchase? Any thoughts would be appreciated. 73, Pete-K8PT > B. Peter Treml [EMAIL PROTECTED] 725 W. Magnetic St. www.qrz.com/k8pt Marquette, Mi. 49855 USA ___ 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 ___ 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
RE: [Elecraft] Question from a newbie
It's all about the source of the noise. My KNB2 has made it possible for me to operate where I'd otherwise have noise pegging the "S-Meter". The KNB2 removes repetitive high-amplitude pulse noise such as that produced by automobile ignition systems, cheap lamp dimmers, etc., that cause a loud "buz" in the audio. It senses the noise pulses and literally turns the signal path off for a very brief period when the next pulse arrives. Other kinds of noise, such as hash from d-c motor commutators or band noise aren't affected by the KNB2. Since large trucks such as you described are invariably diesel powered and so have no ignition system, the most likely source of that noise were the commutators in the d-c motors they use. That produces a hash much like heavy band QRN. The only way to reduce that noise that I've seen yet is a system to digitally process the signal, picking out the noise elements with a sophisticate algorithm. The Elecraft KDSP2 offers that ability. I don't have the KDSP2 in my K2 but the comments from users posted here no the reflector suggest that it's "denoiser" function works quite well. Ron AC7AC -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Fred (FL) Sent: Sunday, March 11, 2007 6:43 AM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] Question from a newbie I built my K2 #54xx in May 06. Built the KNB2 Noise Blanker. Then found it never really seemed to work on any noise! One day, 4 cement trucks & 2 large pickups sat like 30 feet from my shack - all running, all working. The KNB2 did nothing to remove any of that man-made noise. Also it doesn't work on any band noise - that I ever found. I even got a 2nd KNB2, from Elecraft - and it didn't work either? The K2 itself - after build - operated true to all specs, calibrations, & alignments beautifully. I've since felt, the KNB2 is a design job left to be re-done, by some Elecraft designer, when they get around to it. The IC-7000's Noise Reduction and Noise Blanker circuitry - amazingly almost always reduces most band noises, real or imaginary, dramatically. Maybe in the K3? Fred N3CSY 8:00? 8:25? 8:40? Find a flick in no time with the Yahoo! Search movie showtime shortcut. http://tools.search.yahoo.com/shortcuts/#news ___ 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 ___ 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
Re: [Elecraft] Question from a newbie
I made (essentially) the same reply to this identical question when it was posed awhile back. The "4 concrete trucks" and "two large pickups" were almost certain to have had diesel engines and therefore would have had minimal ... if any ... electrical noise to be heard. Even the motors operating the concrete-handling mechanisms would have been hudraulic. Not a good "test" for a noise blanker/eleminator. (;-) 73! Ken Kopp - K0PP [EMAIL PROTECTED] ___ 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
Re: [Elecraft] Question from a newbie
Then you are fortunate enough not to be subject to power line noise at your QTH. Here I've had continuing problems with power line noise (a raspy buzz) and the K2 noise blanker is very effective indeed. Bob NW8L On 3/10/07, Rich McCabe (IWH) <[EMAIL PROTECTED]> wrote: I have had two K2's fully loaded. One with a 38xx serial and the other with a 44xx serial. Mine have never left the desk and I have yet to find any type of noise artificial or other that the NB works on. It's fun to build but in my opinion if you are looking for bang for the buck, that's not it. 73, Rich Kd0zv -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jeff Kinzli N6GQ Sent: Saturday, March 10, 2007 7:22 PM To: Elecraft Mail Posting Subject: Re: [Elecraft] Question from a newbie I have a K2 with DSP, and just last weekend added the KNB2 to the mix. So far, for the noise I have here, the DSP denoiser works much better than the KNB2. I've just been switching it in and out to see what affect it has, and so far haven't found much noise that it removes. I'm in a relatively quiet place though, so that might be it. As Bob said, it's cheap, and it's a kit you can build and install in about an hour or two, so why not!? :) 73, Jeff N6GQ On 3/10/07, Bob Tellefsen <[EMAIL PROTECTED]> wrote: > Pete > It all depends on the type of noise you experience. > For some kinds of noise, the KNB2 works like magic. > For other kinds, it has no effect at all. For some odd > noises, it sort of works. > Ultimately, it's a crap shoot. It is an inexpensive option, > and I would add it as insurance for those times when > it does work. I have it in both my K2s. > 73, Bob N6WG > > - Original Message - > From: "B Peter Treml" <[EMAIL PROTECTED]> > To: > Sent: Saturday, March 10, 2007 4:44 PM > Subject: [Elecraft] Question from a newbie > > > > I have come into possession of a K2/100 with the DSP filter (KDSP2) but > does > > not have the noise blanker (KNB2). > > Question: (1) Is the noise blanker a worthwhile purchase? > > Any thoughts would be appreciated. > > 73, Pete-K8PT > > > > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> > > B. Peter Treml [EMAIL PROTECTED] > > 725 W. Magnetic St. www.qrz.com/k8pt > > Marquette, Mi. 49855 > > USA > > > > ___ > > 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 > > ___ > 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 > ___ 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 ___ 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 ___ 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
Re: [Elecraft] Question from a newbie
While it is true these trucks were probably diesels and therefore there was no IGNITION noise, it is certainly still possible for them to have produced electrical noise. If nothing else, they have alternators. I'm sure we've all heard alternator noise and I suspect the alternators on these trucks are heavy duty, capable of producing heavy duty noise. I'm not up to speed on modern diesel engine technologies, but the fuel pump and fuel injectors might also be electrical these days, not mechanical, as in days of yore (35 years ago when I was a diesel mechanic in the army). 73's, John AA0VE Ken Kopp wrote: The "4 concrete trucks" and "two large pickups" were almost certain to have had diesel engines and therefore would have had minimal ... if any ... electrical noise to be heard. Even the motors operating the concrete-handling mechanisms would have been hudraulic. Not a good "test" for a noise blanker/eleminator. (;-) 73! Ken Kopp - K0PP [EMAIL PROTECTED] ___ 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
RE: [Elecraft] Question from a newbie
True. And in modern equipment, high-current electrical motors are starting to appear more often as alternator/battery technology improves. In general, the number of electrically-powered equipment is on the rise. One thing the KNB2 can handle nicely from a diesel engine is the rare-but-troublesome-when-present staccato noise from some electric fuel injectors. They can be every bit as bad as noisy spark plugs. As Bob observed, *some* power line noise can be removed as well. If something is arcing over cleanly and regularly the KNB2 will kill it. It's the "frying egg" types of noise consisting of a mass of overlapping pulses of varying rates and durations that the KNB2 can't handle. Ron AC7AC -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John R. Lonigro Sent: Sunday, March 11, 2007 10:40 AM To: Ken Kopp Cc: elecraft@mailman.qth.net; Fred (FL) Subject: Re: [Elecraft] Question from a newbie While it is true these trucks were probably diesels and therefore there was no IGNITION noise, it is certainly still possible for them to have produced electrical noise. If nothing else, they have alternators. I'm sure we've all heard alternator noise and I suspect the alternators on these trucks are heavy duty, capable of producing heavy duty noise. I'm not up to speed on modern diesel engine technologies, but the fuel pump and fuel injectors might also be electrical these days, not mechanical, as in days of yore (35 years ago when I was a diesel mechanic in the army). 73's, John AA0VE Ken Kopp wrote: > The "4 concrete trucks" and "two large pickups" were almost certain to > have had diesel engines and therefore would have had minimal ... if > any ... electrical noise to be heard. Even the motors operating the > concrete-handling mechanisms would have been hudraulic. Not a good > "test" for a noise blanker/eleminator. (;-) > > 73! Ken Kopp - K0PP > [EMAIL PROTECTED] > ___ 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
Re: [Elecraft] Question from a newbie
Hi Bob: I wonder if those that see no results from the KNB2 have forgotten to remove a jumper or something? I could not operate without the KNB2. I have line noise that runs 20 dB over s9 at my location on 80 meters (almost as bad on 60, 40, 30, and 20) without the KNB2. Operations of any kind would be impractical. Yesterday morning, I had some pretty horrendous line noise, which the KNB2 completely eliminated... then, in the afternoon I had what appeared to be the same noise (at least it SOUNDED the same to my ears), but the KNB2 couldn't do much at all. Same band, same RX settings, same antenna (and pointed in the same direction), same apparent direction of the noise, but something(!) had changed, to the point that the NB couldn't blank it adequately. Of course, the NB in my TS-950SD couldn't/didn't touch it either! But I agree that the KNB2, when it 'sees' an appropriate noise type, is WONDERFUL. 73, Tom N0SS ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
with the FCC becoming more and more deaf to our pleas to fix broken powerlines and the like ; wouldn't it be great for somebody ( hello Larry LP & Jack PAN) to make a NB widget hat was tunable width /depth and whatever parameters are needed...maybe using his PAN box to examine the junk ??? I know that the scopes on icoms can tell a bunch abt the pulse junk. AND the NB in the K2 still amazes me ... how well it does. bill At 07:17 AM 3/12/2007, Tom Hammond wrote: Hi Bob: ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Perhaps something like the business end of an Evasive Noise Blanker? Jack's PAN box would be a great addition for hunting the rubbish. 73, Geoff GM4ESD - Original Message - From: "Bill NY9H" <[EMAIL PROTECTED]> To: "Tom Hammond" <[EMAIL PROTECTED]>; Sent: Monday, March 12, 2007 1:38 PM Subject: Re: [Elecraft] Question from a newbie > noise blanker with the FCC becoming more and more deaf to our pleas to fix broken powerlines and the like ; wouldn't it be great for somebody ( hello Larry LP & Jack PAN) to make a NB widget hat was tunable width /depth and whatever parameters are needed...maybe using his PAN box to examine the junk ??? I know that the scopes on icoms can tell a bunch abt the pulse junk. ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Actually, a swept spectrum analyzer is a very difficult machine to use for tracking noise, unless the sweep is triggered with the power line zero crossing. If you look at a pulsed waveform from broadband noise with a spectrum analyzer in free run mode (the normal operating mode) you may see some noise spikes drifting around, perhaps moving to the left on the screen; perhaps moving to the right. In the worst case, where the law of perversity applies, the spectrum analyzer's sweep rate will be such that no spikes are seen. If the noise is power line generated and hence has a rep rate of 2X line frequency, then switching the SA to line synch mode will cause the spikes to stand still. The reason for these effects is that a the spectrum of the gap-discharge noise is a line spectrum. If you hook an oscilloscope to a broadband receiver (such as the output of a Z1 buffer amplifier on a K2's post-mixer stage) and if the interference is strong enough and the scope has enough gain (or an auxiliary broadband amplifier is employed) and you set the scope trigger to the power line, you can often see the RF pulse produced each multiple arc and ringing. (The arcs are extinguished every half-cycle in the ordinary case.) If one were to go about an effective noise blanker, I believe you could do much worse than building a new version of the old Collins approach -- a broadband receiver tuned to 30-35 MHz to detect noise and then a fast gate (with suitable delay for synchronization) to clip the received signal. The tunable subtraction units have, in my experience, highly variable effectiveness. I have one here and there are some noise sources that it will work with, but far more that it does not. My experience is that most power companies will fix problems, but they are often not well equipped or staffed to locate problems. The tools of the trade include a wide band receiver in a vehicle, a hand held AM receiver in the 200 MHz band with a built-in yagi, and an ultrasonic receiver with a parabolic dish. In the vehicle, drive around listening to the noise, and keep increasing the frequency as the higher the frequency, the shorter the distance over which it can be heard. If you are fortunate, this will localize it to a few poles (in really severe cases, you can hear the noise up to 600 or 800 MHz). Then, the hand held 200 MHz AM receiver and ultrasonic receiver are used to locate the specific pole or insulator. Like most things, it takes a bit of practice and experience, but the noise sources can be found. In my case, it took Dominion Resources 10 years to find and fix the problem that made it impossible for me to operate below 10 MHz, unless it rained. It turned out to be an arcing wavetrap on a 500 KV line, at a substation perhaps 5 miles from where I live. The 500 KV line runs about 800 feet in back of my antenna and Dominion's EMI techs kept looking for the problem on the transmission line near my house. After the main EMI boss retired, one of his former technicians was promoted and started the hunt from the beginning and zeroed in on the substation. Jack K8ZOA www.cliftonlaboratories.com Geoffrey Mackenzie-Kennedy wrote: Perhaps something like the business end of an Evasive Noise Blanker? Jack's PAN box would be a great addition for hunting the rubbish. 73, Geoff GM4ESD - Original Message - From: "Bill NY9H" <[EMAIL PROTECTED]> To: "Tom Hammond" <[EMAIL PROTECTED]>; Sent: Monday, March 12, 2007 1:38 PM Subject: Re: [Elecraft] Question from a newbie > noise blanker with the FCC becoming more and more deaf to our pleas to fix broken powerlines and the like ; wouldn't it be great for somebody ( hello Larry LP & Jack PAN) to make a NB widget hat was tunable width /depth and whatever parameters are needed...maybe using his PAN box to examine the junk ??? I know that the scopes on icoms can tell a bunch abt the pulse junk. ___ 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 ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Night vision goggles work quite well in some cases. I mentioned it to a friend in the Guard and the 1st Sgt at the local armory decided to have a short training session. The troops spotted the two perpetrator insulators within 2 mins just by looking around. PG&E came out with their IR device in about a week, and it was fixed tFred K6DGW - Northern California Contest Club - CU in the 2007 CQP Oct 6-7 - www.cqp.orghe next day. YMMV ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Fred Jensen wrote: Night vision goggles work quite well in some cases. I mentioned it to a friend in the Guard and the 1st Sgt at the local armory decided to have a short training session. The troops spotted the two perpetrator insulators within 2 mins just by looking around. PG&E came out with their IR device in about a week, and it was fixed tFred K6DGW - Northern California Contest Club - CU in the 2007 CQP Oct 6-7 - www.cqp.orghe next day. YMMV Yes, I can see how that would help. Jack ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Fred, Was this at night? Do you think consumer grade ones would work? Tnx es 73, Leigh/WA5ZNU On Mon, 12 Mar 2007 11:58 am, Fred Jensen wrote: Night vision goggles work quite well in some cases. I mentioned it to a friend in the Guard and the 1st Sgt at the local armory decided to have a short training session. The troops spotted the two perpetrator insulators within 2 mins just by looking around. PG&E came out with their IR device in about a week, and it was fixed tFred K6DGW ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
Understood. I had been pondering a trigger derived from the noise receiver's output pulses but with memory and variable delay added to freeze the display, and allow one or several output noise pulses to be displayed. Jack Smith wrote: Actually, a swept spectrum analyzer is a very difficult machine to use for tracking noise, unless the sweep is triggered with the power line zero crossing. If one were to go about an effective noise blanker, I believe you could do much worse than building a new version of the old Collins approach -- a broadband receiver tuned to 30-35 MHz to detect noise and then a fast gate (with suitable delay for synchronization) to clip the received signal. I agree and use a version. The old Collins system was first used in mobile installations I believe with the KWM-1, but the approach has undergone many changes over the years. Possibly the most significant changes that have evolved for HF use is to reduce the bandwidth of the noise receiver, and tune the noise receiver to a clear frequency close to the system's working frequency to get a more accurate sample of incoming noise. This mutation of the system has become known as the Evasive Noise Blanker, and in Amateur use the noise receiver is tuned to a clear frequency close to but outside of the band in use. From using this type of blanker system for many years I find that a noise receiver tuning range of 25 kHz above each operating band is satisfactory. I opted to avoid using a noise gate in the main receiver's signal chain in the interests of dynamic range, but use the noise pulses to inhibit a fast flip-flop which provides the H-Mode signal mixer with it 50% duty cycle LO squarewave injection, thus having the noise pulses switch injection. This type of blanker will not respond to legitimate in-band signals, a problem sometimes found during contests when using a blanker which samples in-band noise. 73, Geoff GM4ESD ___ 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
Re: [Elecraft] Question from a newbie > noise blanker
There are two different types of night vision. Light amplification and thermal imaging. Since the power company used IR to find the problem, the devices used were likely thermal imaging devices. Light amplifiers must have some light to work, and I don't believe they pick up thermal emissions. Many consumer devices are light amplifiers. David Wilburn [EMAIL PROTECTED] K4DGW K2 #5982 Leigh L Klotz, Jr. wrote: Fred, Was this at night? Do you think consumer grade ones would work? Tnx es 73, Leigh/WA5ZNU On Mon, 12 Mar 2007 11:58 am, Fred Jensen wrote: Night vision goggles work quite well in some cases. I mentioned it to a friend in the Guard and the 1st Sgt at the local armory decided to have a short training session. The troops spotted the two perpetrator insulators within 2 mins just by looking around. PG&E came out with their IR device in about a week, and it was fixed tFred K6DGW ___ 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 ___ 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