Loss of reception on AMC1

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emuman100

SatelliteGuys Pro
Original poster
Dec 15, 2007
247
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Pennsylvania
For some strange reason, I can only get 1 transponder on my 6 footer on W1 C band. I mainly use it for watching DW-TV on transponder 2. Over the past months, the signal would come in great for only parts of the day and night, but then I'd get nothing. This would go in and out, until 3 or 4 weeks ago when I would just get nothing at all, no matter what time of the day or night it was. But, on frequency 3895MHz Vertical 6388 Symbol rate 3/4 FEC I get a strong signal, strongest I've ever gotten, up to 72 to 74% quality on my Visionsat receiver. Everything else I cannot get anything on. Channel scans for Horizontal and vertical polarities come up with nothing except for 3895MHz. I checked the feedhorn, both LNBs, everything is clean. The alignment was never adjusted or moved, the dish never got out of shape or any bolts loosened. The platform I had it on is still nice and level and did not move. Winds never knocked anything out of place. I tried peaking it but cannot get anything except for 3895MHz. Feedhorn did not move, scalar ring did not move, nothing blocking the signal. I cut trees down to give more room, but there was no new growth. This was working fine a few months ago.

Is it something with the signal strength of the transponders, that they just dropped for some reason or is it something with the time of year? I just could not figure it out. I know 6 foot is a small dish but the reception was fine a few months ago.

Thanks.

Jonathan
 
I have a 6 footer on AMC1 too, with quite a few strong tps. I get 3.741V quite strongly at 70% flickering to 85% (which tells me I need to tweak the dish a bit) on a Coolsat 6000. This tp is always quite strong, no seasonal or diurnal variation.

Others are more expert at suggesting what might be the problem, but it sounds as though you might just have some water or other corrosion in the cable. RF travels on the surface of the conductor, and since many cables are copper coated steel you just have a thin layer to carry the signal. If water gets in the copper gets a black film on the surface which has a detrimental effect on exactly the part which is sending the signal.
 
Thanks for the reply. I checked every connector and there was one that had a little rust, but it wasn't the issue, although I replaced it anyway. I have two feed lines going out to the dish for the horizontal and vertical LNB. Both cables are good. I get a little bit of signal from NY state assembly channel on the horizontal and high signal on 3895MHz on the vertical. No matter what I do I can't get any signal on anything else.

Has anyone noticed reception issues with AMC1? I've read that a few months ago there was on smaller dishes. My dish is slightly mis-shapened, but it still picked up the signal with no issue a few months ago. It has to be a seasonal issue, or just an aging bird. Anyone have any thoughts?

Thanks.

Jonathan
 
I've had issues with AMC1 and my 6 foot dish. I use to be able to have AMC1 as an offset LNB on my 6 footer aimed at 99W but recently I have had a bugger getting AMC1 at a good signal other than a couple strong TP's with the other 6 footer aimed directly at it

Lemme try today with the 6 footer and see what I can get
 
wow....AMC1 either has some major issues or I do :)

Monkeyed around with that sat and the 621-2

got 3984 H nice and strong but nothing else came in. Then tweaked it so TLN & Ion were "decent" but then nothing else came in.

I dont know what is going on with that sat
 
Well, for what it's worth, here's what I'm getting with the 10' (just checking for hot TRs)
3741V 69%
3842H 90%
3894V 97%
3910V 90%
3983H 96%
4006H 93%
4074H 90%

11804V 69%
11840H 90%
11880H 93%
12090H 66%
12100V 65%
12115H 70%
12144V 63%
12180V 65%
 
amc-1 is good here on the 10' mesh. You may be getting adjacent satellite interference with the 6' dishes. I am thinking they have have a 3 degree beamwidth on C-band.

If the neighbors have turned on a tp nearly the same frequency or upped the power, that will cause more errors in your signal lowering the quality.
 
I'm in Northeastern Pennsylvania. There are some trees that were in the way, but they never blocked the signal completely. I recently checked 3895MHz (comes in as Powervu Plus Network, which carries TV two channels and one radio) and I'm now getting 79 to 80% quality. I don't know if it was the trees or not. I tweaked the focal depth a little and can now get NY State Assembly channel very unstable, not even holding lock for more than 10 seconds. I couldn't tweak it any better to get a better quality.

Has anyone else, who has a 6 footer, been able to get transponder 2 (V)? I only get 3895MHz on the vertical and 4075MHz on the horizontal. I cannot lock onto anything else. Think this issue will heal itself in time?

Thanks.

Jonathan
 
I have an update. The main issue was the focal distance. Azimuth and elevation were peaked. I peaked the LNB skew and focal distance and I got it. I used a Maxpeak SAM DVB-S meter to do it. I got it on eBay used. It worked like a charm and made the job so so easy. Now it's locked solid. What also helped was the replacement reflector panels I installed to replace two panels that were bent pretty badly when the dish fell down a 40 foot ravine because I never secured it properly. I had to climb down there and roll it back up. :p
 
those poor 6' dishes live a rough life, Iceberg's fell off a table on his deck. Bent it pretty bad.
Those stands or 3 leg mounts are not very stable.
 
those poor 6' dishes live a rough life, Iceberg's fell off a table on his deck. Bent it pretty bad.
Those stands or 3 leg mounts are not very stable.

mine was bolted TO the table and it tipped the table over. Being so far north its very top heavy

Now its on a secure table (where the T90 dish was)
 
With the dish held down with weight it can be very stable. The stand needs to he held down, because with the reflector it is top heavy. I use cinder blocks, 5 of them, and it held it in place since last year. I have it on a wooden shipping palette, but it needs those cinder blocks to stay steady. It was on the wooden palette when it fell down the ravine, also!

With the Fortec 8 footer, I have the same setup, except instead of cinder blocks I have slate rocks. I used them to make a level platform for the wooden shipping palette as well as put them inside, to weigh it down, as well as put more slate rocks on top holding the dish down, like the cinder blocks are holding the 6 footer down.

Now, both the 6 and 8 footer are level, stable, and rock solid. My 36" is mounted in a different way (it has a mast) but just as unconventional. I'll take some pictures soon.

Jonathan
 
yes pics would be great :)

here is a pic of the C-Band on the table....before all the snow
 

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