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Stacking Winegard HD-6065P antennas
"only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one.
John K9RZZ |
#2
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Stacking Winegard HD-6065P antennas
wrote:
"only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg |
#3
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Stacking Winegard HD-6065P antennas
On 1/6/2014 1:28 AM, gregz wrote:
wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. -- ================== Remove the "x" from my email address Jerry Stuckle JDS Computer Training Corp. ================== |
#4
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Stacking Winegard HD-6065P antennas
Jerry Stuckle wrote:
On 1/6/2014 1:28 AM, gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. Exactly. If I got 1 microvolt, 2 microvolts will be twice the signal. Greg |
#5
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Stacking Winegard HD-6065P antennas
On 1/6/2014 10:19 PM, gregz wrote:
Jerry Stuckle wrote: On 1/6/2014 1:28 AM, gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. Exactly. If I got 1 microvolt, 2 microvolts will be twice the signal. Greg No, 2 microvolts would be four times the signal. Remember that power equals the voltage SQUARED divided by resistance. When you double the voltage, you also double the amperage (assuming resistance stays the same). -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
#6
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Stacking Winegard HD-6065P antennas
On Tue, 7 Jan 2014 03:19:54 +0000 (UTC), gregz
wrote: Jerry Stuckle wrote: On 1/6/2014 1:28 AM, gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. Exactly. If I got 1 microvolt, 2 microvolts will be twice the signal. Greg Sorta. If you got 1 microvolt, 2 microvolts will be twice the signal voltage but only 1.414 times the signal power. That's why we have units of measure to avoid such ambiguities. Just to be difficult, working with antennas, the "signal" is the field strength measured in dBuV/M. If you define what you're measuring and specify your units of measure, you wouldn't be having such problems. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#7
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Stacking Winegard HD-6065P antennas
On 1/6/2014 11:04 PM, Jeff Liebermann wrote:
On Tue, 7 Jan 2014 03:19:54 +0000 (UTC), gregz wrote: Jerry Stuckle wrote: On 1/6/2014 1:28 AM, gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. Exactly. If I got 1 microvolt, 2 microvolts will be twice the signal. Greg Sorta. If you got 1 microvolt, 2 microvolts will be twice the signal voltage but only 1.414 times the signal power. That's why we have units of measure to avoid such ambiguities. Just to be difficult, working with antennas, the "signal" is the field strength measured in dBuV/M. If you define what you're measuring and specify your units of measure, you wouldn't be having such problems. You've got it backwards, Jeff. Twice the voltage is 4 times the power. 1.414 times the voltage would be twice the power. -- ================== Remove the "x" from my email address Jerry, AI0K ================== |
#8
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Stacking Winegard HD-6065P antennas
On Mon, 06 Jan 2014 23:23:56 -0500, Jerry Stuckle
wrote: On 1/6/2014 11:04 PM, Jeff Liebermann wrote: On Tue, 7 Jan 2014 03:19:54 +0000 (UTC), gregz wrote: Jerry Stuckle wrote: On 1/6/2014 1:28 AM, gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Twice the voltage is a 6 db gain. Twice the power is a 3db gain. Exactly. If I got 1 microvolt, 2 microvolts will be twice the signal. Greg Sorta. If you got 1 microvolt, 2 microvolts will be twice the signal voltage but only 1.414 times the signal power. That's why we have units of measure to avoid such ambiguities. Just to be difficult, working with antennas, the "signal" is the field strength measured in dBuV/M. If you define what you're measuring and specify your units of measure, you wouldn't be having such problems. You've got it backwards, Jeff. Twice the voltage is 4 times the power. 1.414 times the voltage would be twice the power. Very embarrassing. Temporary loss of IQ from working on my broken car with a cold or flu this afternoon. It should be: If you got 1 microvolt, 2 microvolts will be twice the signal voltage but 4 times the signal power. Thanks for the correction (grumble)... Maybe if I go to sleep early, when I wake up tomorrow, this didn't happen. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#9
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Stacking Winegard HD-6065P antennas
On Mon, 6 Jan 2014 06:28:11 +0000 (UTC), gregz
wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Nope. Power is by the square of the voltage: P = V^2 / R If you double the voltage, you get 4 times the power. A 1.414 times increase in voltage will produce twice the power. I tried to convert the antenna model of the HD-6066P antenna from the AO .ant format to .nec using 4NEC2 and failed. The plan was to model the stacked arrangement and see what happens: http://www.ham-radio.com/k6sti/hd6065p.htm The .ant file imported without error, the wire tables and images look correct, but the pattern is more like a point source than a gain antenna. I'll look at it later to see where I screwed up, but it would be nice if someone would look at the problem. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#10
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Stacking Winegard HD-6065P antennas
"Jeff Liebermann" wrote in message ... On Mon, 6 Jan 2014 06:28:11 +0000 (UTC), gregz wrote: wrote: "only 3 db", but that's twice the signal. I have mine stacked 12 feet, but I believe Winegard says either 8 or 10 feet. Mine work swell. +:^] I got mine just after they were discontinued in 2005/6. Had to email a number of suppliers until I found the second one. I bet there are some still in storage somewhere, email different places that sell Winegard, you may still find one. John K9RZZ Twice the signal means twice the voltage, for me. Greg Nope. Power is by the square of the voltage: P = V^2 / R If you double the voltage, you get 4 times the power. A 1.414 times increase in voltage will produce twice the power. I tried to convert the antenna model of the HD-6066P antenna from the AO .ant format to .nec using 4NEC2 and failed. The plan was to model the stacked arrangement and see what happens: http://www.ham-radio.com/k6sti/hd6065p.htm The .ant file imported without error, the wire tables and images look correct, but the pattern is more like a point source than a gain antenna. I'll look at it later to see where I screwed up, but it would be nice if someone would look at the problem. I just set up an experiment. I connected my roof antenna to my signal level meter and read the signal strength of my Channel 10. It was 10 dBmV, the unit typically used for TV signal strength work. Next, I connected the same roof antenna to the inport port of one of a pair of passive splitters connected back-to-back with equal short lengths of the same 75-ohm cable. Finally, I connected the output port of this network to the signal level meter and observed a signal that was approximately 1.25 dBmV less. (A quarter of a dBmV is about as close as I can reliably read; individual whole number marks are only a few mm apart.) Thus, I conclude that the 1 dB nominal loss for a passive splitter -- either combining or splitting -- is confirmed. Combining two identical suignals does get you something more than one, alone. RELATED: When I used identical twin UHF antennas side-by-side, separated by a free-space half-wave distance to cancel interference from one side, it worked nicely and showed about the same loss figures as above. That is, my reading for two antennas combined was about 2 dBmV higher than for either of the twin antennas alone, thus reflecting the 1dB loss in the combiner. Combining antennas can be an uncertain business because the phase relationships change with wavelength; the arrangement that strengthens one channel may weaken another channel if the respective signals come from different directions and/or the cable lengths are not matched. It's a matter of reinforcement or cancellation, depending on phase relationships. "Sal" (KD6VKW) |
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