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About a year ago my system got flakey and noticed my feed horn half full, or half empty, of water.

I live in orlando, so I drilled two 1/8 inch holes in it, one on top of the oval and one on the bottom. The water ran out.

It has stayed dry to this day and works well.

I didnt know what else to do, but it still works.

James Healey, SatMex 5

As a preventative measure, I recommend a supermarket or Wal-Mart plastic bag tied over the entire head of the LNB.

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I have one of the original 1st year production "direcPC'" feedhorns. Mine was one of the first that "sprang a leak" and filled up with water. I cut out three sides of the "window" with a razor and drained the water. Then, I heated it up over the furnice register. I then taped it back together with 2 inch wide clear packing tape.

That was 3 years ago. The tape has dried and the window fell out completely and there is just a hole.

I keep a fresh grocery plastic bag over it at all times, with NO problems - a good signal, a little "baggie" tacky, BUT ...
---- NO TROUBLES in the past three years. This is really not a big problem. ----

You just need to keep water out of the feedhorn and the hole that water leaks in (usually around the window somewhere there is a hole in the glue).

Marvn Mochel
Sat 91 Earthlink 4000 modems

Vic Gray--K6JPJ

I have the problem of condensation in the feedhorn. It seems that this is common problem. My Signal Strength dropped from 55/58 to 43/45. I took the protective plastic weather shield off to visually inspect the LNB, waveguide, and feedhorn assembly. Condensation pretty well covered the inside of the feedhorn oval cover. After a few hours, the condensation was reduced by about 50%. The next day, the condensation had disappeared.

Taking off the weather cover seems to have allowed the LNB, etc. to thermally adjust to match the outside temperature. Warm air holds more moisture than cold air, and as every RVer knows, moisture will appear on the barrier between hot and cold air, like window panes or, i.e., feedhorn covers.

My receive signal level is now back to normal. I think the protective cover traps heat in the feedhorn, which expels some air during the day. At night, during cool down, it sucks in moist outside air and eventually results in condensation.

When the monsoon season here ends, in another month, I will delve into the reason that allows moist air to make its way inside the feedhorn. There's probably a pinhole around the feedhorn window or a waveguide flange seal problem. A little silicon sealant ought to fix most of the problem.

From my experience with shipboard radars, the feedhorn cover doesn't even have to be there. It has no effect on the signal level in the transmit or receive mode. It does protect the horn inside surfaces from corrosion and insects. Drilling small holes to allow water to drain shouldn't hurt anything, but I wouldn't recommend it. Its best to try and find where the outside air is getting into the assembly so moisture can be kept out.

My experience parallels this exactly.

I am an electrical engineer, and if you know compulsive, you know what an EE is.

My first course of action when mine leaked was complicated and extensive, to say the least. It would have made my old lab professor proud. The %#!! Thing leaked again, and right now!

Being a true EE, there followed failure analysis, controlled experiments,
yada, yada, yada.

It leaked.

FINALLY, I cut the $%@&&#! Window out in frustration and put a baggie over it's head.

It has stayed dry and worked like a charm ever since.

I kinda like how it looks. The baggie is what engineers call an elegant solution .

Best regards,
Mike

To keep the window dry I drilled a hole in the window and dried it out in the motorhome overnight when it got wet. A piece of tape over the hole worked to keep the rain out. Also, if it was a dry day I would remove the tape and let it dry.

Gregg Melde

I just had the TxCode 18 problem. It turns out that my feed horn was 1/3 full of water. I removed the plastic cover and drained the water. It took a little while for the feed horn to dry and finally it connected fine.

Alright all of you. I am becoming almost ex-pert on this water stuff.

First everyone make sure your 4 screws that mount the horn are tight. If they are and you have no evidence of water on the lens or enough water to put a goldfish in then take some clear silicone sealant and run a bead of it around the edge of the lens over onto the horn metal. At the split between the horn and the rest of it run some silicone sealant all the way around that split. You can wet a finger in a soap solution and smooth the silicone nicely. Let the sealant cure, 4-6 hrs will do.

Get a clear plastic freezer bag and cover the horn and put it back as far as you can get it to go. Quart size is a good start. Making sure the smooth seamless portion of the bag is over the lens. Using wire ties, string, wire electrical tape or whatever, wrap around the horn area to hold the bag in place. This will work on tripod mount or MotoSat dishes.

If your Motosate Datastorm Administrator or Don's Administrator shows your signal quality bouncing between about 29 up to 33 and back but you have a high SS better be looking up there in the lens. If it is just moisture and it is hot and sunny it may go away in the after noon and you can hook up but in the cool morning hours you will not be able to hook up.

I have never taken the lens off but have removed the whole horn and swabbed it out with long Q Tips and then have put it in the wifes counter oven on the lowest setting for a half hour or so then turn the oven off and let it cool down inside. Put it back up there with a small amount of grease to hold the oring in place...you didn't loose it did you? ... and you can use vasaline it is mostly just to hold the oring in place.

It is the oring that seals the assemblies to each other not the lubricant. Many will argue this but whatever. When you get the horn back on then refer to first paragraph as how to seal it up.

You may see some white corrosive by products if you have had water in the horn and you should work on that with whatever it takes to remove those products. If...there really was a lot of water there does exist the posibility that the water got down into the wave guide and into the rest of the system. A lot of work to see if that has happened but doable. Harder to do up on the roof. Swing the dish around to a point where you can take a lightweight beach chair or similar up on the roof and get a comfortable safe sitting position. Most of our knees are shot at this age. Get comfortable while you work up there...but please be careful.

After reading about the loose screws I went outside and checked mine. Guess what? 4 loose screws ... all of them loose enough to slip a credit card behind the washer. My unit has only been in service about 6 weeks. I would suggest that every one should check their feedhorn for loose screws. They have a lock washer on them so they shouldn't loosen up.

Seems to me that QC is not doing their job. (Former QC person).

We're seeing some systems getting loose screws after a year or more of being handled and moved. Six weeks seems a bit short.

I've started using a silicone sealer on the contact surfaces in addition to the "O" ring and screws when I assemble the feedhorn. I think the handling and the temperature changes may contribute to the loosening, so that has become another maintenance point to check, just like checking your cables and connectors.

You might think about sealing the wave guide/feed horn connection and checking the other screws while you're at it. You may want to put some silicone sealant on the screws and on the metal surface on and outside the "O" ring. Not much, just enough to keep the screws from loosening and to seal the contacting surfaces.

I think what's happening to folks is that these screws loosen up with time and movement, aluminum expansion and contraction coupled with handling causes the screws to back out and maybe the "O" ring to shrink a bit.

I've seen a rack at Home Depot of "O" rings in a variety of sizes; That should be a good place to look. Ace Hardware often has better "misc" hardware than Home Depot.

I'd swab out and air dry the unit (hair dryer?) before reassembly and I'd silicone and seal the connection with 100% silicone sealer.

I wouldn't do anything that would obviously void the warranty such as drain holes in the cover.

Good luck and please keep us all posted. I'm seeing more posts about this problem this year than last and I'm wondering if it's a developing problem for more users or if the percentage is static and we just have more users.

I worked in a field where we used o'rings to seal vacuum systems. O'ring can be from many materials, but are probably not real rubber. The reason for the grease is to seal little imperfections in all the surfaces, such as machining marks, etc. Silicon grease is very good for this. It's also very important that all the surfaces be clean. I wouls clean them with a lint free cloth wetted with alcohol. Lens cleaner would also be good. Also if I was having a problem I'd examine the surfaces with a magnafying glass to make sure there are no scratches etc.

Thanks for the feedback, Glenn. Unfortunately, putting a pinhole in the lens is what my installer told me to do yesterday. When it didn't help with getting rid of the moisture, I posted today to this group and got lots better advice. I never realized that a pinhole could void the warraty on the feedhorn since my installer recommended it.

The moisture went away nicely taking the feedhorn loose as per Don's recommendation. There is a lot of white powdery oxidation inside the eedhorn up close to the lens with particles of it on the inside of the lens that I can't get at. Is that going to affect the performance of the unit?

I got most of the white aluminum oxide out of the LNB by putting a piece of wet paper towel on the end of a "tool grabber" (for want of a better term) and was able to swish it around to loosen most of the oxide. Have it back in the sun to dry out again.

Would blue Loctite work as well on the screws as silicone sealant or just use the sealant on screws and O ring and flat surfaces like you suggested in an earlier reply to me, Glenn?

As long as I can remember I have always used Armor All on all my seals and gaskets, commode, regri, snap on hose attachements with o-rings?

Armor-All is really hard on rubber and actually causes it to rot prematurely (in spite of manufacturer claims). Vaseline or any other petroleum-based product will do the same. A little bit of silicone grease, just enough to wet the O-ring is recommended but not necessary. After the joint is sealed with the O-ring in place and the screws tight, a little bit of silicone sealant or Goop on the screws to keep them from rotating out is, I believe, what Glenn Simpson was talking about.

You can find silicone sealant at a SCUBA shop - it is used in lubricating equipment o-rings prior to assembly.

This is just a note to let everyone know that I have started using a dielectric grease in the connectors of all the cables used outside in setting up the sat dish. All shorting by rain and humidity have gone away. What a simple solution to a problem.

I have been using the dielectric grease for some time now with no problems other than the dirt (it doesn't bother me)and have had no problems with dropped signals even in heavy rains like we experience in South Florida. I actually put the tip of the tube alongside the center conductor and FILL the connection. I have really had no problems at all. In fact I now also use it for hooking up my Directv cables...we move every two weeks.

I have read all the psts in this thread with interest. I am wondering if you really used the dielectric grease "in" or "on" the connectors. My experience with putting dielectric grease "in" the connectors is that the grease interferes with the signals and causes all kinds of disconnects and other problems. The only way I was able to fix the problem was to flush and clean all the connectors. I have read that some guys use silicone lube on their connectors and it seems to work well for them. I spent the summer on the Oregon coast, where the month of May was a torrent. I didn't use grease or anything else on my connectors and had no problems with them. I did have the problem of a feed horn that had so much water in it that it could have sustained a small guppy.

Holey maloley - finally something I know something about here.


Anybody know what "dielectric" means? It means no electric shall pass. That grease is an insulator. Now why do some people say to
use it inside connectors?

Its properties supposedly allow it to be "moved aside" when the metal contacts touch. Well, I'm no chemistry whiz, but you can't convince me that ALL of the molecules of that stuff get "moved aside". Anybody who puts it inside coax or similar connectors is risking gradual failure of the connection, especially when it ages and the contact pressure starts to weaken from wear, vibration, whatnot. Shoot, at that point the "moved aside" stuff is probably going to creep back in!

After the connection is tightened, it might be useful on the outside, but grease attracts dirt. Silicone or even nail polish is going to seal the outside better. I really have no idea what this stuff is truly useful for. So now I will leave it to the dealer/installer folks who do use this stuff, especially inside the connections, to explain exactly why they do.

I'm not a dealer/installer, but the answer to the question is obvious - it is the subject line of this thread!

The tiniest amount of moisture inside the connector - the TINIEST amount - will cause more problems than is possible with just about any amount of molecules of dielectric that might - MIGHT - get between the two metal surfaces!

Corrosion, particularly of the copper center conductor, is a big cause of problems with these sensitive internet connections. I've taken apart connections that were sealed with dielectric two years earlier, and there was no corrosion of the conductor at all. Can't say the same when no grease was used, or when an o-ring was used.

I agree with Don's explanation and will go a little further,

Back a hundred years ago <g> when I was a young shaver in Electronics Engineering school, they taught us about good electrical connections and "gas tight joints". That phrase really means that for good electrical connections to be good and remain good, the two "wires" must be tight enough so NO air (or other 'nasties' like salt spray at the beach) can penetrate the connection point and start corroding. This is why a tight connection is required.

With all that said, I have hated "F" connectors ever since then. They are not the best connector we could be using, but unfortunately we are stuck with them. I read with interest the discussion about a year ago about using BNC connectors in place of "F" connectors. "F" connectors were kind of OK for inside the house in the early days of cable TV, but now we are expecting them to be almost 'microwave' connectors.

As most have found out, it is the center connector that is the main 'trouble maker'. Because it uses plain copper (or even worse copper clad steel), it is already corroding before you even start hooking up the dish when the cable is manufactured. A more 'noble' metal such as gold would be much better (but way too expensive), but even nickel wouldn't tarnish as quickly. BNC connectors do have a actual "contact" at the center instead of just
stripped wire. Using a good quality dielectric compound inside the connector is the best thing we can do to try and seal out the corroding gases and create that 'gas tight joint' that we all want. IF you have the thought that it is an insulator and therefore is a bad thing, that means that your connectors are already bad. IF they had a tight grip on that center conductor as they should, the 'grease' would only be sealing out the air. IF the grease is causing you problems, it is either the wrong kind of stuff (as always, good folks might sell the wrong stuff due to bad suppliers or not understanding the basic science - not to mention the scam artists around every industry - anything for a buck types). Assuming that the grease isn't contaminated and that the connectors are good to begin with, the grease can only help stop the corrosion problem with the bare copper center conductor in a F connector. IF the "mess" is objectionable, my recommendation is to make pigtails to the factory connections and grease them up and use the new ends as your make and break connections. IF you do this, be prepared to replace these connectors (both male and female) every few months, more often when near the beach and/or monsoon seasons. Once the center conductor 'grippers' no longer 'grip', you will have bad connections as a chronic problem and every time you open it up and reconnect it, you will scrub some corrosion off and "fix" it for a short while, but it will return.

Americans (and most other folks) want a "quick fix and forget" life as well as most also want to buy the lowest cost item (or the discount store wants to sell you the lowest cost item while telling you that it is the best that money can buy). I guess that this is how the "F" connector has lived this long, and it does work OK for most, but it is also the source for grief for lots of folks and good hard earned cash is spent in waste due to them.

So, given new, good connectors, the dielectric grease is the best insurance that you can get for long term 'trouble free' connections. It will NOT fix a weak or corroded center gripper in an old connector. It will be messy in everyday on and off connectors. Electrical tape and/or silicone glue and/or finger nail polish are only stop gap "fixes" (closing the barn door after the cow gets out) and may help, but the grease makes a physical seal to the air that is the main culprit.

I installed cable (TV) for several years before retiring. We were issued a dielectric grease and this grease was NEVER installed within the cable. It was applied outside after the connection was made, and then a rubber boot was slipped over the connection.

Additionally, great care was taken that all the insulation was removed from the center conductor, as well as making sure no fragments from the shielding shorted out a bright connection. It only stands to reason, that with the additional care that needs to be taken with these connectors, that the application of ANYTHING that may degrade the connection (an insulator) should be avoided at all costs.

Interestingly enough, another option for preventing the penetration of moisture into the internal working of the connection is when the compression (or crimped) fitting is pushed onto the properly prepared cable, you push it through a tiny bit further (approx 1mm) than normal. This allows the center insulation to seat against the barrel (female) connector and seal the center conductor from outside contamination. With due precautions, the outside portion (shield) can also be sealed, whether with tape, nail polish, or dielectric grease.

Clearly this has reached an insurmountable impasse and my personal opinion is that those who believe in di-electric will always believe in di-electric and continue to use it. Those that do not will still not. Thanks to everyone for their input.

To help put this subject to rest I will quote FSB_050518_01C:

Inspect all outdoor F-connectors and replace them with compression type connectors from the HNS approved list in Table 1 and weatherproof them with dielectric grease and silicone tape. Use self-fusing sealant such as Mocap or GB Electronics silicone tape.

All F-connectors installed outdoors must be filled with dielectric grease before connecting to the radio or ground block and then wrapped with a self fusing tape such as MOCAP orGB Electronics silicone tape. Install the F-connectors on the cables and fill them with dielectric grease.
Dielectric Grease

- CROSS DEVICES "STUF" (Available through local and online distributors) - STUF Dielectric water proofing filler for electronic connectors.

- SYNCO Super-Lube (Available through local and online distributors) #21030 3 oz. tube/#41160 400 g. jar - Multi purpose PTFE synthetic grease that can be used as a dielectric water proofing filler for electronic connectors

- BOSS® 440/Perfect Vision (P-10)/PVSG440 - Silicone General Purpose Compound designed as a protective compound for electronic and electrical apparatus.

Weatherproof Tape

- MOCAP (Available through local and online distributors) - Silicone self fusing tape Used to wrap outdoor connectors to provide additional weather protection.

- Gardner Bender/GB Electronics (Available through local and online distributors) - Silicone self fusing tape Used to wrap outdoor connectors to provide additional weather protection.

Note:All the above text was directly copied from Hughes FSB Available to all installers. This is a HNS Spec install.

This week I set up at the beach for a 6 months stay. Sand is a real problem and if you drop the cable end only once it picks up grit.

I found that a can of compressed air, Q-tips and a can of contact cleaner really help. By running the Q-Tip around the inside of the connector helps to remove the grit. (Having "True Grit" is not always good.

A small piece of Black sandpaper [silicone carbide] used on the center conductor to brighten it up makes a big difference.

If I could find an EXTREAMLY SMALL, FINE wire brush it would help to scrub the inside threades of the fitting.

All this followed by grease seems to seal very well.

WD40 is used an all other moving metel parts to prevent rust.