diversity receive what bands
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Hi everyone,
I am new to the idea of diversity receive and wonder if this is mainly used on the lower bands, 160, 80 and 40 meters or all amateur radio bands. Regards, Renze VE6DC |
Re: diversity receive what bands
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For me 40m and up only, usually used on the higher bands but with my
antennas works well on 40m also. 73, Fred/N0AZZ -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of ve6dc Sent: Saturday, November 09, 2013 12:43 PM To: [hidden email] Subject: [Elecraft] diversity receive what bands Hi everyone, I am new to the idea of diversity receive and wonder if this is mainly used on the lower bands, 160, 80 and 40 meters or all amateur radio bands. Regards, Renze VE6DC -- View this message in context: http://elecraft.365791.n2.nabble.com/diversity-receive-what-bands-tp7580624. html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3222/6322 - Release Date: 11/09/13 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: diversity receive what bands
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In reply to this post by ve6dc
On 11/9/2013 10:42 AM, ve6dc wrote:
> I am new to the idea of diversity receive and wonder if this is mainly used > on the lower bands, 160, 80 and 40 meters or all amateur radio bands. It's most useful when there is QSB, or when signals are arriving at different vertical angles or when there is selective fading. Much QSB is the result of multiple copies of signals that arrive by slightly different paths, and are thus a bit out of time (and phase) by virtue of slightly different travel times. The result is heard as "picket fencing" with short VHF/UHF wavelengths, very slow QSB with the 200X longer wavelengths on 160M. When the two arrivals are nearly equal and close to 180 out of phase, they cancel, often by as much as 20 dB, and when in phase, add by as much as 6 dB. With diversity RX, the concept for this sort of fading is to have antennas separated by some significant fraction of a wavelength, so that when the arrivals are cancelling at one, there will be addition (or at least less cancellation) at the other. For the other situation of high angle vs low angle paths, using a vertical antenna that favors low angles and another antenna (Beverage or low horizontal dipole) that favors high angles. An excellent place to study these the propagation concepts is the ON4UN Low Band DXing book. The fading caused by cancellation of multiple arrivals is not widely understood by hams on the HF bands and 160M, but it is VERY well understood by many audio professionals working in live sound. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: diversity receive what bands
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Jim,
I always thought of Beverage as directional antenna that favors low angles. Is it not so? Regarding diversity, I always use two antennas (usually beaming West and East) practically on all the bands. This helps not only to fight multy path propagation but allows listening to weak signals from the east on sub RX without AGC being offset by strong signals from the west. This is invaluable capability for those, working pileup in contests. 73, Igor UA9CDC > least less cancellation) at the other. For the other situation of high > angle vs low angle paths, using a vertical antenna that favors low angles > and another antenna (Beverage or low horizontal dipole) that favors high > angles. > 73, Jim K9YC > ______________________________________________________________ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: diversity receive what bands
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Igor
Your correct I have receive only antennas that I use on that port for receive only antenna. Diversity I use a vertical with my yagi to even out a signal that comes and goes works great. 73, Fred/N0AZZ -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Igor Sokolov Sent: Saturday, November 09, 2013 4:46 PM To: [hidden email]; [hidden email] Subject: Re: [Elecraft] diversity receive what bands Jim, I always thought of Beverage as directional antenna that favors low angles. Is it not so? Regarding diversity, I always use two antennas (usually beaming West and East) practically on all the bands. This helps not only to fight multy path propagation but allows listening to weak signals from the east on sub RX without AGC being offset by strong signals from the west. This is invaluable capability for those, working pileup in contests. 73, Igor UA9CDC > least less cancellation) at the other. For the other situation of > high angle vs low angle paths, using a vertical antenna that favors > low angles and another antenna (Beverage or low horizontal dipole) > that favors high angles. > 73, Jim K9YC > ______________________________________________________________ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2242 / Virus Database: 3222/6323 - Release Date: 11/09/13 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: diversity receive what bands
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In reply to this post by ve6dc
I find diversity reception useful on 20 Meters when operating on the Alaska Pacific net. One antenna is a Beam pointed toward Alaska. The diversity antenna is a Vertical. With this arrangement I get the nulls in the beam pattern filled in with the vertical and can hear operators off the side and back of the beam that would be down 20+DB with just the beam. The same works for DX and pail-ups.
John Hendricks K7JLT On Nov 9, 2013, at 10:42, ve6dc <[hidden email]> wrote: > Hi everyone, > > I am new to the idea of diversity receive and wonder if this is mainly used > on the lower bands, 160, 80 and 40 meters or all amateur radio bands. > > Regards, Renze VE6DC > > > > -- > View this message in context: http://elecraft.365791.n2.nabble.com/diversity-receive-what-bands-tp7580624.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: diversity receive what bands
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In reply to this post by Igor Sokolov-2
On 11/9/2013 2:46 PM, Igor Sokolov wrote:
> > I always thought of Beverage as directional antenna that favors low > angles. Is it not so? Beverages tend to favor higher wave angles, while verticals favor low angles. Those who have lots of land like to install both Beverages and vertical RX arrays (Hi-Z Antennas, DX Engineering are US companies that sell them). I've seen reports of signals appearing an hour earlier on one antenna than the other, then disappearing from the first antenna. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by ve6dc
Used also on 6m -
http://www.g3tct.co.uk/diversity.html Graham ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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In reply to this post by Jim Brown-10
Beverages and vertical arrays actually have very similar takeoff angles (e.g. 25-40 degrees). Salt water dramatically lowers the lowest takeoff for verticals and a poor ground will raise it. Lengthening Beverages will also lower the takeoff angle. See Graph 3 below for an example of the latter on 160: http://www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/Beverage.htm At 1 wavelength (~540' which is about the minimum useful Beverage length) the takeoff angle is 42 degrees. Lengthening it to 2 wavelengths lowers the angle to 27 degrees. Below are two plots (top and very bottom) of my antennas which demonstrate the difference between a low dipole (90 degree takeoff), a vertical array (22 degree takeoff) and a 2 wavelength Beverage (24 degree takeoff): http://users.vnet.net/btippett/new_page_10.htm I normally use Beverages on one port and an RX4SQ on the other port. I can also switch between the RX4SQ and my TX array (Spitfire variant). On 80 and 160 I use diversity almost 100% of the time. 73, Bill W4ZV |
Re: diversity receive what bands
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Bill
A very nice antenna farm you have for sure! If I might ask how long is your feed line from the beverage and the 4sq's to your shack? And the TX 160m distance and feed line used helix I'm guessing? 73, Fred/N0AZZ Monett, MO. -----Original Message----- From: [hidden email] [mailto:[hidden email]] On Behalf Of Bill W4ZV Sent: Monday, November 11, 2013 5:28 AM To: [hidden email] Subject: Re: [Elecraft] diversity receive what bands Jim Brown-10 wrote > Beverages tend to favor higher wave angles, while verticals favor low > angles. Those who have lots of land like to install both Beverages > and vertical RX arrays (Hi-Z Antennas, DX Engineering are US companies > that sell them). I've seen reports of signals appearing an hour > earlier on one antenna than the other, then disappearing from the first antenna. Beverages and vertical arrays actually have very similar takeoff angles (e.g. 25-40 degrees). Salt water dramatically lowers the lowest takeoff for verticals and a poor ground will raise it. Lengthening Beverages will also lower the takeoff angle. See Graph 3 below for an example of the latter on 160: http://www.seed-solutions.com/gregordy/Amateur%20Radio/Experimentation/Bever age.htm At 1 wavelength (~540' which is about the minimum useful Beverage length) the takeoff angle is 42 degrees. Lengthening it to 2 wavelengths lowers the angle to 27 degrees. Below are two plots (top and very bottom) of my antennas which demonstrate the difference between a low dipole (90 degree takeoff), a vertical array (22 degree takeoff) and a 2 wavelength Beverage (24 degree takeoff): http://users.vnet.net/btippett/new_page_10.htm I normally use Beverages on one port and an RX4SQ on the other port. I can also switch between the RX4SQ and my TX array (Spitfire variant). On 80 and 160 I use diversity almost 100% of the time. 73, Bill W4ZV -- View this message in context: http://elecraft.365791.n2.nabble.com/diversity-receive-what-bands-tp7580624p 7580677.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3426 / Virus Database: 3222/6826 - Release Date: 11/11/13 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Hi Fred,
Loss is generally not a problem for RX antennas on the low bands because it's low (even for RG6) and ambient atmospheric noise is high. The RX4SQ uses a run of 800' and the Beverages use from 200-500', all RG6. The TX antenna uses about 350' of surplus 7/8" Heliax which replaced RG8 several years ago. That gained <1 dB but it was cheap and much more rugged than RG8. 73, Bill
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In reply to this post by ve6dc
Thank you Fred, Jim, George, Igor, John, Art, Graham and Bill for responding to my quest for more information about diversity receive, I have learned a lot.
Regards, Renze VE6DC |
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