Tests of 120cm antennas

OK, back to some tests. As I am going to remove Fibo 120 from balcony and install CM1,2m instead of it, I just scanned 7*W. Got 50 transponders and average SNR from them 58,66%. These data may be some kind of reference for future CM tests. Weather conditions: some clouds and also stars are visible. Did not touch Fibo 120 for a long time, hope it is more or less tuned.
 

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After yesterday's last Fibo-scan removed Fibos and installed CM1,2m. It was drizzling and I was under time pressure as my family usually watches some show from 4,8*E. Unfortunately T90 does not provide some channels from 4,9*E in my area, especially in the evenings. So, tuned CM to 4,9*E and will leave it like this till next time. Actuator will not be used to move antenna, it is just to fix it in vertical position. When I move to 7*W I would like antenna to stay vertical, not on polar-mounted position, that is to be able to measure elevation precisely.
IMG_20150221_090253 (Large).webp IMG_20150225_174923 (Large).webp IMG_20150225_175245 (Large).webp IMG_20150225_175258 (Large).webp
 
RimaNTSS said:
OK, back to some tests. As I am going to remove Fibo 120 from balcony and install CM1,2m instead of it, I just scanned 7*W. Got 50 transponders and average SNR from them 58,66%. These data may be some kind of reference for future CM tests. Weather conditions: some clouds and also stars are visible. Did not touch Fibo 120 for a long time, hope it is more or less tuned.
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Did you take these reading from a meter or the receiver?
 
jase1 said:
I'm about 10% down on those figures on the two I've just checked
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Do not forget you are much more NW from my location, so, maybe this is normal to have less signal.
 
Here are my results measured on my Dr HD F15 (jbl = just below lock) Weather conditions, some cloud, a few stars visible

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I picked up 2 additional tp's to Rima, no 29 & 43, nos 33, 34 and 35 were unable to lock.

My latitude is very similar to Rima, 50.8 N, he is about 4.4° East of me.
 
RimaNTSS said:
After yesterday's last Fibo-scan removed Fibos and installed CM1,2m. It was drizzling and I was under time pressure as my family usually watches some show from 4,8*E. Unfortunately T90 does not provide some channels from 4,9*E in my area, especially in the evenings. So, tuned CM to 4,9*E and will leave it like this till next time. Actuator will not be used to move antenna, it is just to fix it in vertical position. When I move to 7*W I would like antenna to stay vertical, not on polar-mounted position, that is to be able to measure elevation precisely.
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That dish and polar mount look as good as new, you made a nice job of cleaning them up! It must be your wife's expensive shampoo that makes a difference! :D
 
In reality, polar mount has several places where is no paint but rust. But I will take care of it when tests are over.
 
RimaNTSS said:
In reality, polar mount has several places where is no paint but rust. But I will take care of it when tests are over.
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As a "temporary" fix, hasn't your wife got any expensive body lotion that you could "rub" over the rust to help hold it at bay! :D
 
That sounds like perversion :D will better use some kind of grease or use nothing - let it rust :rolleyes:
 
How are the test being performed please, blind scan ? are feeds included ? same time of day ?, I can get a difference of 5/10 more/less TP from my last three concurrent scans. if I pull away E from no 29 so I don't lock it I get more TP, rimants should have no problems locking no 29 ?
 
Riverblue said:
I picked up 2 additional tp's to Rima, no 29 & 43
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I've found out 11602H is not included in my satellite.xml file, so it was not scanned. I do not know why 12321V did not show any sign of life - magic. :eek:

martin-f said:
How are the test being performed please, blind scan ? are feeds included ? same time of day ?,
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Friend of mine (very big SAT-nut :D ) made script for Enigma 2, so after it is activated, receiver starts to scan all transponders on chosen satellite/satellites and puts all data about locked transponders in file. In another file it puts transponders could not be locked. No blind scan, and especially on 7*W when 8*W is nearby. Feeds will be included if frequencies are present in lamedb file. Will try to do all tests at the same time of the day. However, I think that I can manage to do 2 scans (LNB in original LNB holder and LNB in another holder) within 1/2 hours.
 
I did my test at 7.00pm, receiver blind scan, fixed dish, conditions not bad. The three tp's just below lock I have had them before, but I don't get a strong signal on them, they are all on Nilesat 102, all of the tp's on Nilesat 102 are not very strong. Maybe if this was on a motorised set up I could gain a bit by nudging the dish a bit eastwards for those specific tp's. I didn't count the feeds that I picked up. :)
 
Riverblue said:
I did my test at 7.00pm, receiver blind scan, fixed dish, conditions not bad. The three tp's just below lock I have had them before, but I don't get a strong signal on them, they are all on Nilesat 102, all of the tp's on Nilesat 102 are not very strong. Maybe if this was on a motorised set up I could gain a bit by nudging the dish a bit eastwards for those specific tp's. I didn't count the feeds that I picked up. :)
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Many thanks Andy, I am not usually a critic but we have a few factors that could be debated,
 
"Tin hat on!" :D Debate away :p

Is blue good
Yellow (yellow) so so
and red bad? o_O
 
Lol pal no tin hats needed :), they are all debatable talking extreme fringe and can be good/bad :),


I don't like to be a critic so i am on my way :)
 
Just checked: My satellite.xml file does not have 11602 H and 12321 V frequencies, but if I scan them individually than it gives signal. By now I will not count those frequencies as my Fibo 120 is removed and I am not going to install it again.
Last frequency from my list was 12627 V 2220, and I have no idea to which satellite it belongs to :( I can scan it from 7*W position but can not find in KoS or LyngSat frequency's list.... I am puzzled here. Appreciate if somebody shed some light on it. ScreenHunter_195 Feb. 27 20.14.webp
But here we have another issue: Frequencies 11938V, 11996H, 12034H, 12072H, 12130V and 12226H belong to transponders from Nielsat 120 at 7*W.
But, at the same time all another frequencies are from Eutelsat 7 West A with orbital position 7,3*W.
So, there is difference of 0,3* between those two satellites and when we tune antenna at it's maximum on 7*W then all transponders from 7,3*W maybe receivable but they are not received at maximal signal power. And vice verso. Therefore, for the sake of clarity of experiments, I would propose to exclude those 6 frequencies from list of our test table.
What else I did today! Yes, turned antenna (horizontally by hand) and tuned antenna to 7,3*W with IBU in original CM holder. IMG_20150227_171002 (Large).webp
Measured leaning of dish and it was 7,6*, but knowing from LyngSat that 7,3*W for my location has elevation 30,7* by adding 7,6* + 22,6* (antenna's offset angle) got 30,2*. Which means that mistake is about 0,5*. If weather allows, than tomorrow will repeat measuring leaning of antenna with more precise tuning of it, to have clear prove of this strange mistake made by CM contractors.

P.S. bad news- because of sea-state there is no fishing tomorrow :eek:
 
And forgot to tell, I scanned 7,3*W (IBU in original CM holder), got data, excluded 6 frequencies belonging to 7*W and updated my table. So, from comparing performance of Fibo 120 and CM 120 I clearly see that my Fibo system performed almost 6% better than system based on CM 120 dish. Which is understandable, Gregorian systems should perform better than usual offset dishes about 10% better.
ScreenHunter_196 Feb. 27 21.35.webp ScreenHunter_197 Feb. 27 21.36.webp
 
Different test dates between the fibo 24. 02. 15 and the CM 27. 02. 15.
Were test conditions ( weather, temp, cloud, rain ) similar?
 
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