Re: Topband: WATCH OUT !!Did you get a new cable modem from Comcast? Arris Modem equal lots of QRM
Jameco continues to sell linear wall warts, if you want them new. best wishes, Nick VE7DXR At 05:26 24-10-14, you wrote: On 10/23/2014 3:33 PM, JC wrote: So watch out is you have Comcast cable modem, it is necessary to choke the cable and the AC cord with FT240 # 31. With this fix ,the noise dropped from s8 to s0 but still audible at Doug receiver. By now this should be "Ham Radio 101" -- that is, assume that EVERYTHING with a digital clock, and EVERY switching power supply is a noise source, and be prepared to choke them using my RFI tutorial as a starting point. It's also a VERY good move to replace all switching power supplies with a linear supply, or even a linear supply float charging a battery. I'm doing exactly that with cable modem, WiFi Router, CATV box, Internet "radio," etc. In most cities, it's possible to find linear wall warts at second hand stores for a buck or less, and I also buy them at ham flea markets. And all the gear in my shack (except for computers and power amp), run off my small solar system. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: KP1
Thanks Herb for the note and memories. I found my KC4DX card. Worked on 20M back in 1972 when I just had received general class privileges. At the time I had no idea I had worked a "rare one." I used the Heath SB-401/SB-300 and a Hy-Gain vertical. KC4DX's main radio was the Swan 500C radio. Wayne Green, W2NSD/1 was one of the ops. Yes, the Wayne Green. More info. about KC4DX here. http://kc4dx.com/ Looking forward to working KP1 on the Top Band. - Jon N0JK > > Message: 1 > Date: Fri, 24 Oct 2014 00:34:47 + (UTC) > From: Jeff Wilson > To: "topband@contesting.com" > Subject: Re: Topband: KP1 > Message-ID: > > <1464259376.198200.1414110887279.javamail.ya...@jws100111.mail.ne1.yahoo.com> > > Content-Type: text/plain; charset=UTF-8 > > Thanks for the memories Herb.I was surprised to see you had the KV4FZ > call way back then! > I just dug out my K4IA/KC4 Navassa Island SWL QSL to VE3PE2NL (thanks Popular > Electronics!)? from June 24, 1969...20m SSB 0411Z QSO with WA6ROU.? Now > finally a chance for a real QSO, and on Top Band!!!? QSL showed a B&W photo > of nasty cliff side landing zone.? All Drake RX/TX pairs.? Thankfully it is > not in the Indian Ocean!? Can't wait for Januarywill have to put up the > South Beverage, but probably won't need it with this team!? Best Wishes, 73 > Jeff VE3CV > _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Boradband noise on 160 meters tracked down to apartment complex
Recently noticed an increase in my noise level on 160 meters (in the direction of my 300 degree pointed pennant), and about 3 weeks ago I tracked it down to a new apartment complex which is located 0.41 miles away. Today I noticed that the signal had a repeating pattern of approximately 30 minutes on and 5 minutes off when listening at my house, so I jumped in the car and drove over to the apartment complex to make sure the signal at the apartment complex had the same repeating pattern and was in time sync with the noise at my house. Thankfully it was, and I made recordings at the apartment complex today showing I could predict when the signal would go off and come back on based on the time pattern I was following at my house. I have created a website documenting my direction finding activities for this broadband RFI case, and uploaded my prediction recording today. Here is the link to my simple website that documents this case : http://sites.google.com/site/broadbandrfi/ I contacted the apartment complex today notifying them that I was now 100% confident that the broadband noise was originating from their building, and will now work with their management to locate the exact source so they can follow up with the manufacturer of the equipment for resolution. Based on what I have heard so far it sounds like a motor (probably a variable speed motor controller), but that's just a guess at this time (sounds like it's winding up in speed when it first comes on and you can hear this on the recording I made at the apartment complex today). Just FYI, and another very interesting one to track down. 73, Don Kirk (wd8dsb) _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Boradband noise on 160 meters tracked down to apartment complex
Just a helpful tidbit for anyone working with motor controllers / drives / VFDs / frequency drives / etc. (lots of names for the things :-): The manufacturers usually specify that the wiring between the VFD and the motor be in conduit. This is to help with EMI/RFI issues. There is usually also a relatively short maximum reach specified (20-50 feet or so). Obviously they mean *metal* conduit for shielding, but I've seen electricians use plastic conduit -- especially for flexible applications -- before. The flexible conduit is commonly known as "Sealtite" in the trades even though that is just one manufacturer of the stuff. It's normally a flexible metal conduit with a plastic outer jacket. There is also an all-plastic version of the stuff. You can tell them apart by the look and feel once you've seen both, but another way is that the jacket markings on the "metal inside plastic" kind will say something about needing to use a separate grounding wire if the circuit is more than some number of amps. The all-plastic kind will not have that marking. The reason for the marking is that the steel part of the conduit is thin and usually can't be a suitable ground connection for safety purposes for more than 20-30 amps or so. There is also the usual flexible metal conduit (usually known as greenfield, or "MC cable" (for "Metal Clad" cable) if it has factory installed wires) which has a spiral metal outer "jacket" that is conductive. If your noise source ends up being some kind of motor drive, I'd check to make sure the wiring between the drive and the motor are in some kind of metal conduit. It's an easy thing to look for and might also be the cause of the problem. -Bill > -Original Message- > From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of > Don Kirk > Sent: Friday, October 24, 2014 2:41 PM > To: topband > Subject: Topband: Boradband noise on 160 meters tracked down to > apartment complex > > Recently noticed an increase in my noise level on 160 meters (in the direction > of my 300 degree pointed pennant), and about 3 weeks ago I tracked it down > to a new apartment complex which is located 0.41 miles away. Today I > noticed that the signal had a repeating pattern of approximately 30 minutes > on and 5 minutes off when listening at my house, so I jumped in the car and > drove over to the apartment complex to make sure the signal at the > apartment complex had the same repeating pattern and was in time sync > with the noise at my house. Thankfully it was, and I made recordings at the > apartment complex today showing I could predict when the signal would go > off and come back on based on the time pattern I was following at my house. > > I have created a website documenting my direction finding activities for this > broadband RFI case, and uploaded my prediction recording today. Here is > the link to my simple website that documents this case : > http://sites.google.com/site/broadbandrfi/ > > I contacted the apartment complex today notifying them that I was now > 100% confident that the broadband noise was originating from their building, > and will now work with their management to locate the exact source so they > can follow up with the manufacturer of the equipment for resolution. Based > on what I have heard so far it sounds like a motor (probably a variable speed > motor controller), but that's just a guess at this time (sounds like it's > winding > up in speed when it first comes on and you can hear this on the recording I > made at the apartment complex today). > > Just FYI, and another very interesting one to track down. > > 73, > Don Kirk (wd8dsb) > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: just in time for CQWW
At 2200Z an X6 class solar flare erupted directly in line with the earth. Major disruption of radio propagation can be expected for the next 6 to 10 hours according to NASA. If a CME results further effects may become effective during the next several days. Check spaceweather.com for developing information. _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: instant update on solar flare
at 2210z the intensity of the flare was downgraded to an x1.9 still pretty bad for ionosphere though and the possibility of further flaring within the next 24 hours is listed as around 40% _ Topband Reflector Archives - http://www.contesting.com/_topband
