I have several locations that I work at that are having issues with 2 particular Transponder signal levels. On a receiver it is identified as 103s Transponder 21 and Transponder 22. Using an AIM2 meter with the "with spots" transponder test, what transponder would i be looking for? On 103a there is a transponder 21 but not a transponder 22 and 103b does not have either. Some of the customers have hotel style systems so i am unable to get the 103s levels, and the levels that their system is way different that either a receiver or an AIM so it is impossible to correlate them.
Transponder Cross Reference
- Thread starter Wrecker347
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There isn't any point to trying to differentiate between conus and spot beams coming from the same slot when it comes to aiming.
If you're trying to figure out which spots you're in the cone of you may be just as well off to use Satbeams and not have to do a physical site survey.
If you're trying to figure out which spots you're in the cone of you may be just as well off to use Satbeams and not have to do a physical site survey.
I am not trying to aim the dish. I know what spots I am in. I am trying to be able to identify the signal level of a particular spotbeam using the AIM. When I am at a customers site and all I have to be able to get usable signal levels is the AIM I would like to be able to accurately say "this is the signal I am wanting to see" so I can better determine if it is an equipment issue or DTV has reduced power levels or what ever that is affecting the ability for them to receive the channels.
There isn't anything you can do about the spot beam's power levels other than point a finger.
Doesn't the COM3000 give you all the signal strength details through the management interface that a conventional receiver would? That seems much easier than taking the system offline to plug in an aiming meter.
The frequency and polarity of the transponders on 103S are different than 103CA and 103CB. You have to be tuned to the 103S transponders to see their signal strengths. DIRECTV uses two bands of frequencies for these transmissions: The KAHi or "A" band and the KALo or "B" Band. 103CA is the Nationwide transponders in the A Band. 103CB is the Nationwide transponders in the B band, using TPNs 1 to 14. 103S shows the spot beams on the B Band at 103, using TPNs 15-24. (It used to also show TPNs 1-8 of the A band when they had spot beams, but that satellite has been retired.)
The two spot beam transponders carrying New Orleans local channels are on TPNs 21 and 22, both at 18732 MHz, one with Left Hand Circular Polarization (LHCP), the other with RHCP. They use the spot beam antenna called A4B5. I have attached a file which when opened with Google Earth, displays the beam footprint for those transponders. The short answer is that a usable signal for a normal sized DirecTV dish extends out only 70 to 75 miles into the Gulf from the Louisiana shoreline.
P.S. I am an Engineer. not a technician. I have never seen an AIM meter. The above information comes from analyzing FCC licensing documents.
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KMZ files aren't a valid filetype on this forum, so they can't be attached directly, here's the link to it off the /resources page:
D12_A4B5_NewOrleans.kmz
D12_A4B5_NewOrleans.kmz
Other references i have found show that a4b5 is for Jackson Mississippi and that T10 a2b7 is the new orleans beam..... but my main question is how can i measure the Strength, SNR and SQ of this transponder with an AIM. The COM2000 system only gives the SNR and Signal Level. Or can someone give me the equation that is used to compute SQ from the values i have.
Your other references are terribly out of date. T10 (D10) spot beam transponders were shut down over a decade ago, after some sort of system failure on the satellite. T12 (or D12 as DirecTV has reverted to this year) took over it's spot beam duties. New Orleans Stations are positively on D12 B Band transponder 21 and 22, using beam A4B5. See the Satellite Transponder Tables.
I use Genpix Skywalker-1 receivers and TSreader for a lot that I do here, I can't receive the Ka band satellites, but my experience on the Ku Band is that a SNR of at least +6dB is necessary for
{EDIT} Make that any reception, and we aren't rrying to receive video, just metadata, like the APG gude data. I normally see a SNR of about 14 to 15DdB on my Skywalker receivers receivers.
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Digging through some old files, I found the attached graph that correlates Signal Strngth reported by the DirecTV receiver to SNR. It was produced by an associate around 2015.
