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Discussion Starter · #1 ·
All,


Just a suggestion.


If you go ahead and upgrade your Paratodos package eliptical Channelmaster dish to have Sat A, B, and C, you may want to consider upgrading the internal cabling at the same time.


I noticed that they use what looks like RG-59 or low quality RG-6 cables and connectors.


I went and got 100 feet of RG-6U (quad shielded) and some ends and redid all my wiring from the LNBs down to the back of the reciever. After repointing the dish, I am getting over 80 points on all the Sat A transponders (from minneapolis) and getting 6 or more with 90+. Sat C is in the 80s for its transponders.


Sat B is a bit flakey, in that it still only gets in the high 50s.


I made 5 2foot cables and 1 6inch cable and used shrink fit tubing on all the connetors. I sealed it all up with clear silicon calk for peace of mind.


Over all, my signal strength went up almost 6 points across the board, and, the signals are alot more stable and don't fluctuate as much as before. (everything is +/- 1 point, not 4 like before!)


SHOWH and HBOH come in CRYSTAL clear.

(until it snows next week)


Just a suggestion.


-Warlock
 

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Discussion Starter · #3 ·
DTC mac,


I tried looking for RG-11 and found it only online. (MinneSNOWta does not have a great abundance of cable suppliers...that I know of, at least)


Going with quad shielded and taking special care to get the connectors all setup correctly makes the world of difference, though.


Again, signal stability has been the biggest advantage over anything else. Even though stregth did go up a tad. ;)


Regards,


-Warlock
 

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Do not use silicone caulk. It contains and releases acetic acid when curing. Smells like strong vinegar. If it has this smell DO NOT USE around electronics. Recalling my chemistry- this produces both Aluminum acetate and Ferric acetate, a non conductive powdery substance that will degrade the signals at the connections that have been contaminated with the silicone caulking. Instead, Scotch makes an electrical moisture proofing compound intended for this purpose. Find it in the electrical sections at Home Depot. Silicone RTV or caulking will corrode and acid etch the shielding and connectors over a short period of time. You should never use this in connection with electronics or antennas and coax wiring.


If you have already used the silicone then it will work for awhile but not long lasting like using the proper material. Be prepared to replace the cables and connectors in a few months as your signal becomes slowly funky while the connectors corrode away.


Re RG11- Good for very long runs but will the F connectors work with this? Do they make F connectors for RG11? Been awhile since I worked with RG11 but I think you may find a PL258 or 9 ? to F adapter. Bring me up to date on this. I'd like to know since it's been awhile. Personally, I deal with around 100 ft runs so RG 6 works great!
 

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Don't waste your money on RG-11. Its calculable but microscopic difference in RF loss will not be a factor in your system's reliability.


There are RG-11 F connectors available, and some of the suppliers will even sell them with silicone gel in their outer sleeves, but none of my suppliers are presently offering them with the internal "O" rings like the outdoor-style RG-6 connectors have (called F-56 connectors). The chief engineer for one of the largest MDU system operators on the east coast told me his company stopped using RG-11 coax in hi-rise buildings because the RG-11 "F" connectors were less reliable and often reflect certain narrow bands of frequencies within the DBS L-band, so his systems perform better with RG-6.


I maintain DirecTV systems with coax runs as long as 1,500 feet (big condominium, single community reception antenna). The longest run consists of 1,100 feet of RG-11, followed by 400 feet of RG-6, passing through four high-powered amplifiers. The final 200 feet of the RG-6 is bargain-grade coax. The signal strength readings on the Sony B-65 receiver at the end of that run vary from the low 80s to the low 90s with most being around 88. I have seen receivers in this same system that are just 400' from the community antenna produce less impressive signal strength numbers.


The so-called signal strength numbers displayed by DBS receivers are not really measures of signal strength, but no one "in the know" has ever said publicly what they mean, and if anyone responds in this thread claiming to know, then he probably doesn't know unless he was one of the engineers who actually designed that circuitry.


You receiver needs a certain thresholds signal-to-noise ratio to be able to process the digital signal, and its absolute signal level only needs to fall within a huge range. Your signal strength can actually vary over ten thousand fold without any discernible effect on your receiver's operation. A bench technician I talked to said he tested several Sony receivers with inputs varying from -26dBm to -66dBm without the receiver's "signal strength" numbers varying in any consistent manner, but others experimenting with other makes of receiver have seen these signal strength numbers jump up and down with changes in receiver input strength.


What you are most concerned with is resisting the effects of "rain fade", which is the weakening of the broadcast signal caused by by rain. Rain fade directly reduces the signal-to-noise ratio. Saving a fraction of a decibel of signal strength at your receiver by substituting RG-11 for RG-6 will have no effect on your signal-to-noise ratio and, unless your receiver is on the end of a 400 foot or longer line with no amplification, it will have no effect on your systems resistance to the debilitating effects rain fade.


Basically, when you can improve your receiver's signal strength numbers by increasing the antenna gain, you will have done a beneficial thing. You can do that by more accurately aiming the dish or by installing a larger dish. When you improve those numbers by using larger coax or by inserting a line amplifier, you usually will not have improved your situation at all, the lone exception being when you genuinely have low signal strength (well below -60dBm) as measured on a field strength meter, not by your receiver's primitive signal strength indicator.


The gain of LNBs varies within a range of 50 to 62dB. In the real world, a residential system functions no differently with an LNB with a 50dB gain than with one with a 62dB gain. It is just possible that Warlock's Sat B LNB has gain at the lower end of that range, and his receiver's primitive signal strength algorithm perceives its resulting lower output level to be inferior to the output of his Sat A LNB, when it is not.


Warlock should swapping his Sat A and Sat B LNBs, if he has not already. Otherwise, wait for the next rainstorm and see if programming on satellite B drops out well before programming from Satellite A and C does.


You can never make things worse by replacing the old F-connectors, F-81 barrel splices and grounding blocks with new ones, and doing so can often make things better . Radio Shack sells rolls of coax sealant for about $3.00 that can be used to waterproof them.
 

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Thanks for the info on the RG11 although I don't think I would ever need to consider using it here. For F connectors I like the cheap RS twist on type. I use a little bit of Scotchcote to seal them and cote them to the connection aftyer made for a good moisture seal. Haven'y had any problems with that sealant yet as it was designed for electrical moisture proffing.
 
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