Outside the 2nd story window
Pending a permanent installation, I now have the antenna outside my 2nd story window (pictures pending), hanging from the 2nd story rain gutter (plumbing PVC piping/fittings make excellent mounting fixtures!). This has resulted in about a 6dB increase in signal strength. Questions (from "interface wireless monitor 0"): 1. "Signal-strength" (I take it this is receive signal strength?) typically runs -86dBm to -90dBm; "tx-signal-strength" typically runs about 5dB better, although I have seen them the same. With the same radio at both ends (the other end is the DEM at Paine), I would think they would usually be the same, except for possible reflections, which I would think would be "equal opportunity" in occasionally giving a better value to the receive value, but that never happens. 2. What is "current-distance"? It's showing as "10" or "11". I'm exactly 5 miles from the Paine DEM, so I would have thought that this might be the round-trip distance, except I would have thought that a physical distance would be reported in kilometers (the manufacturer being outside of the USA). Now I do not have to leave the window open ... -- Dean AE7Q
On 2014-03-21 18:05, Dean Gibson AE7Q wrote:
Pending a permanent installation, I now have the antenna outside my 2nd story window (pictures pending), hanging from the 2nd story rain gutter (plumbing PVC piping/fittings make excellent mounting fixtures!). This has resulted in about a 6dB increase in signal strength. [...] Now I do not have to leave the window open ...
-- Dean AE7Q
Previous (inside): http://www.ae7q.net/media/5.9GHz-1.jpg http://www.ae7q.net/media/5.9GHz-2.jpg Outside: http://www.ae7q.net/media/5.9GHz-3.jpg http://www.ae7q.net/media/5.9GHz-4.jpg -- God left a gap in the (many) trees, right in the path to Paine field ... Pictures from outside coming tomorrow ...
On 2014-03-23 15:25, Dean Gibson AE7Q wrote:
On 2014-03-21 18:05, Dean Gibson AE7Q wrote:
Pending a permanent installation, I now have the antenna outside my 2nd story window (pictures pending), hanging from the 2nd story rain gutter (plumbing PVC piping/fittings make excellent mounting fixtures!). This has resulted in about a 5dB increase in signal strength. [...] Now I do not have to leave the window open ...
-- Dean AE7Q
Antenna inside (-89dBm):
http://www.ae7q.net/media/5.9GHz-1.jpg http://www.ae7q.net/media/5.9GHz-2.jpg
Antenna just outside the window (-84dBm):
http://www.ae7q.net/media/5.9GHz-3.jpg http://www.ae7q.net/media/5.9GHz-4.jpg -- God left a gap in the (many) trees, right in the path to Paine field ...
The initial outside location, from the street ... http://www.ae7q.net/media/5.9GHz-5.jpg http://www.ae7q.net/media/5.9GHz-6.jpg Move the antenna 8 feet east for a 9dB signal strength increase (-75dBm = three green lights (power/ethernet + two signal "bars") ... http://www.ae7q.net/media/5.9GHz-7.jpg http://www.ae7q.net/media/5.9GHz-8.jpg http://www.ae7q.net/media/5.9GHz-9.jpg The nice thing about the mounting, is that there is NO attachment to the house, which makes adjustment trivial (sliding the mounting hooks in the rain gutter). Even the Ethernet cable goes through pre-existing screening in attic vents. The whole thing can be removed from the house without a trace in 20 minutes (10 minutes, if one is young and agile, which I am neither). It's (reasonably) light-weight (another plus, for the same personal reasons). Bart -- you are free to use the pictures in your MicroHams talk tomorrow.
Resent (delete previous copy of this message), as editing a URL apparently doesn't change the underlying links (stupid Thunderbird).
On 2014-03-21 18:05, Dean Gibson AE7Q wrote:
Pending a permanent installation, I now have the antenna outside my 2nd story window (pictures pending), hanging from the 2nd story rain gutter (plumbing PVC piping/fittings make excellent mounting fixtures!). This has resulted in about a 5dB increase in signal strength. [...] Now I do not have to leave the window open ...
-- Dean AE7Q
Antenna inside (-89dBm): http://www.ae7q.net/media/5.9GHz-1.jpg http://www.ae7q.net/media/5.9GHz-2.jpg Antenna just outside the window (-84dBm): http://www.ae7q.net/media/5.9GHz-3.jpg http://www.ae7q.net/media/5.9GHz-4.jpg -- God left a gap in the (many) trees, right in the path to Paine field ... The initial outside location, from the street ... http://www.ae7q.net/media/5.9GHz-5.jpg http://www.ae7q.net/media/5.9GHz-6.jpg Move the antenna 8 feet east for a 9dB signal strength increase (-75dBm = three green lights (power/Ethernet + two signal "bars") ... http://www.ae7q.net/media/5.9GHz-7.jpg http://www.ae7q.net/media/5.9GHz-8.jpg http://www.ae7q.net/media/5.9GHz-9.jpg The nice thing about the mounting, is that there is NO attachment to the house, which makes adjustment trivial (sliding the mounting hooks in the rain gutter). Even the Ethernet cable goes through pre-existing screening in attic vents. The whole thing can be removed from the house without a trace in 20 minutes (10 minutes, if one is young and agile, which I am neither). It's (reasonably) light-weight (another plus, for the same personal reasons).
Prior details in the eMails below ... Shortly after the -75dBm report below, I started to see the value drop to a usual range of -77-80dBm, with occasional excursions down to -83dBm. I spent three long sessions (one getting wet) out on the roof, to no avail (I carry an Android tablet logged into the MikroTik radio, to observe the effects of small adjustments). The variations did not seem related to rain, although a wet antenna seems to drop the signal about 2dB. Interestingly, during the night there was little change, but the commute hours seemed to generate the most fluctuations. I think that's because the line-of-sight path runs about 20ft above 132nd St SE, a busy street connecting I-5 and Highway 9 at the north end of Mill Creek. Perhaps the signal is bouncing off of vehicles? I originally thought that perhaps the decrease from the initial -75dBm to -78dBm was perhaps due to foliage growth (this is Spring, after all). However, in the last week I've seen a very slight increase (1-2dB) in the average signal level, so I don't know what to make of that. Perhaps someone has been picking flowers, or Bart has been climbing the SnoCo DEM antenna tower and making adjustments (just joking)? Anyway, the reason for this idle posting is just to record my observations for others to consider. I have thought of raising my antenna a couple feet using a similar gutter mount. I then considered that would probably place the center-of-mass above the gutter, which would make the whole thing unstable in a strong wind without a 3rd attachment point. What appears to be the lower "attachment point" in the images, is in fact just contact bracing, with gravity providing a constant contact. That's nice when the whole thing is stable with regard to pivoting around the gutter axis (as it is now), not so nice otherwise. Yes, I could weight the lower end down to lower the center of mass, but right now the weight is enough to make hanging the thing on the gutter difficult, when standing on a slanted roof ... -- Dean On 2014-03-29 08:09, Dean Gibson AE7Q wrote:
Antenna inside (-89dBm), to test the site:
http://www.ae7q.com/misc/media/5.9GHz-1.jpg http://www.ae7q.com/misc/media/5.9GHz-2.jpg
Antenna just outside the window (-84dBm), from inside:
http://www.ae7q.com/misc/media/5.9GHz-3.jpg http://www.ae7q.com/misc/media/5.9GHz-4.jpg -- God left a gap in the (many) trees, right in the path to Paine field ...
... and from outside ...
http://www.ae7q.com/misc/media/5.9GHz-5.jpg -- frontal view http://www.ae7q.com/misc/media/5.9GHz-6.jpg -- in the line of fire ...
Move the antenna 8 feet east for a 9dB signal strength increase (-75dBm = three green lights (power/Ethernet + two signal "bars") ...
http://www.ae7q.com/misc/media/5.9GHz-7.jpg -- frontal view http://www.ae7q.com/misc/media/5.9GHz-8.jpg -- in the line of fire ... http://www.ae7q.com/misc/media/5.9GHz-9.jpg -- side view
The nice thing about the mounting, is that there is NO attachment to the house, which makes adjustment trivial (sliding the mounting hooks in the rain gutter). Even the Ethernet cable goes through pre-existing screening in attic vents. The whole thing can be removed from the house without a trace in 20 minutes (10 minutes, if one is young and agile, which I am neither). It's (reasonably) light-weight (another plus, for the same personal reasons).
Yeah, signal levels bounce around quite a lot. I see swings much larger than 5dB on my link, and I attribute that to the trees I'm shooting through. We did a few calibrated signal level measures once, from Cougar to a couple remote spots. The levels did not match theory. We didn't use the modems, but a proper sine wave signal source and spectrum analyzer on the receive. To this day, I don't have an explanation for the deviation from theory. It would be good to graph your signal levels and see if they're related to anything. Wind, traffic, temperature, time of day, etc. If you wanna get really fancy, you can find a 2nd spot that's workable somewhere on your property, install a 2nd dish, replace the modem with a 2-channel one, and start doing spatial diversity. I don't think anyone's done that yet, although we have done polarity diversity. You can log the signal strengths from each channel independently with such a setup, and see if there's some correlation over time. Science! --Bart On 04/18/2014 03:19 PM, Dean Gibson AE7Q wrote:
Prior details in the eMails below ...
Shortly after the -75dBm report below, I started to see the value drop to a usual range of -77-80dBm, with occasional excursions down to -83dBm. I spent three long sessions (one getting wet) out on the roof, to no avail (I carry an Android tablet logged into the MikroTik radio, to observe the effects of small adjustments). The variations did not seem related to rain, although a wet antenna seems to drop the signal about 2dB. Interestingly, during the night there was little change, but the commute hours seemed to generate the most fluctuations. I think that's because the line-of-sight path runs about 20ft above 132nd St SE, a busy street connecting I-5 and Highway 9 at the north end of Mill Creek. Perhaps the signal is bouncing off of vehicles?
I originally thought that perhaps the decrease from the initial -75dBm to -78dBm was perhaps due to foliage growth (this is Spring, after all). However, in the last week I've seen a very slight increase (1-2dB) in the average signal level, so I don't know what to make of that. Perhaps someone has been picking flowers, or Bart has been climbing the SnoCo DEM antenna tower and making adjustments (just joking)?
Anyway, the reason for this idle posting is just to record my observations for others to consider. I have thought of raising my antenna a couple feet using a similar gutter mount. I then considered that would probably place the center-of-mass above the gutter, which would make the whole thing unstable in a strong wind without a 3rd attachment point. What appears to be the lower "attachment point" in the images, is in fact just contact bracing, with gravity providing a constant contact. That's nice when the whole thing is stable with regard to pivoting around the gutter axis (as it is now), not so nice otherwise. Yes, I could weight the lower end down to lower the center of mass, but right now the weight is enough to make hanging the thing on the gutter difficult, when standing on a slanted roof ...
-- Dean
On 2014-03-29 08:09, Dean Gibson AE7Q wrote:
Antenna inside (-89dBm), to test the site:
http://www.ae7q.com/misc/media/5.9GHz-1.jpg http://www.ae7q.com/misc/media/5.9GHz-2.jpg
Antenna just outside the window (-84dBm), from inside:
http://www.ae7q.com/misc/media/5.9GHz-3.jpg http://www.ae7q.com/misc/media/5.9GHz-4.jpg -- God left a gap in the (many) trees, right in the path to Paine field ...
... and from outside ...
http://www.ae7q.com/misc/media/5.9GHz-5.jpg -- frontal view http://www.ae7q.com/misc/media/5.9GHz-6.jpg -- in the line of fire ...
Move the antenna 8 feet east for a 9dB signal strength increase (-75dBm = three green lights (power/Ethernet + two signal "bars") ...
http://www.ae7q.com/misc/media/5.9GHz-7.jpg -- frontal view http://www.ae7q.com/misc/media/5.9GHz-8.jpg -- in the line of fire ... http://www.ae7q.com/misc/media/5.9GHz-9.jpg -- side view
The nice thing about the mounting, is that there is NO attachment to the house, which makes adjustment trivial (sliding the mounting hooks in the rain gutter). Even the Ethernet cable goes through pre-existing screening in attic vents. The whole thing can be removed from the house without a trace in 20 minutes (10 minutes, if one is young and agile, which I am neither). It's (reasonably) light-weight (another plus, for the same personal reasons).
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participants (3)
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Bart Kus -
Dean Gibson AE7Q -
Dean Gibson AE7Q