Does having multiple RJ45 jacks degrade the Internet signal a lot?

I assume you're able to connect to the WISP radio via your broadband router. That's what routers do, they act as an interface between two or more networks.

That doesn't look quite as good as I'd hoped. Just thinking out loud, I wonder if you'd get more stability, more protection from the elements, and more protection from general damage by putting the vertical run inside a small conduit, and solidly attaching the conduit to the pole.

Reply to
Char Jackson
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Duh... or, you could just add a right angle Type-N connector and just move the radio out of the way.

I have a few if you're in a hurry (i.e. before it rains).

Also:

That doesn't look like it has much concrete in the ground. It's probably just fine when the ground is dry, but I hate to see what will happen when the ground gets wet, and the nearby tree branches start wacking the pole around. It's not going to fall over, but it might move around enough to loose the path:

Hmmm... are you sure the pipe is 16ft long? Judging by the height of the nearby picnic table (about 30" high), the mast looks like it's about 25ft high.

Reply to
Jeff Liebermann

Ummm... make that about 31ft:

Perhaps that might explain why you consumed so much CAT5?

Reply to
Jeff Liebermann

When I look back at it, it 'does' look a little shoddy just wrapped around the pole like a barber-shop twist.

That's a GREAT IDEA!

I could also, I guess, put the wire INSIDE the water pipe mast but I like the idea of strapping PVC conduit to the pole, alongside the pole, with the wire running down.

PS: I wish I thought of that 'before' I did it - but this suggestion will help others and I can do it in my retrofit when I add the TV antenna!

Reply to
Chuck Banshee

Hi Jeff,

My mistake for not providing useful data.

The hole goes 3 feet down inside a steel pipe sunk in the concrete (see pictures below). The soil is not like yours as you're on the western side of the fault line. You have topsoil on top of Gabrilan granite (the Salinian block).

I have highly deformed & easily broken up chert on the eastern side of the fault line, formed in the bottom of the Pacific Ocean when my side of the San Andreas fault was the edge of the continent.

I'd better run the calculations you suggested & report back.

Here are some pictures of the concrete & steel setup:

  1. This is the existing hole in the ground:
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  2. This is my ingenious (perhaps ludicrous) attempt at fitting a two-inch pipe in a 3.5 inch hole!
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  3. I modified a plastic 3 inch to 2 inch conduit bushing (removing the lip with a Dremel tool) as shown here:
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  4. I listened to the suggestion to use anti-seize on the threading:
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  5. Then I took 2 inch and 1.5 inch water pipe and strung them together:
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  6. Being all alone, holding pipe free to twist on threads was easier said than done:
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  7. Then I shoved the whole contraption 3 feet into the existing ground hole:
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  8. The bottom length is about six feet of 2 inch water pipe:
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  9. The top of the antenna is about 16 feet up:
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    Picture #7 above is the key problem.

I don't know if the plastic bushing will hold up (I wish I could have found a steel 3" to 2" adapter). Plus it's only at the top (with the bottom of the pipe three feet below able to wobble).

With no wind, it's sturdy - but winds easily top 120mph out here (more sometimes) so that might be a problem.

Here's the height:

- About 6 feet of 2" threaded water pipe stuck about 3' into the ground.

- A 10 foot length of 1.5 inch threaded water pipe

- A 2 foot length of 1.5 inch threaded water pipe

- Then antenna is about a foot square (give or take)

I'll do the calculations on the web site you suggested to find the loads.

Reply to
Chuck Banshee

Hi Jeff,

I appreciate the calculations.

You even made ME wonder if I had bought a 20 foot pipe instead of 10 feet!

It turns out that the table, because it's far away from the mast, looks deceptively small.

Here is a shot with a 3-foot yardstick and a 2-foot square next to the mast:

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Here is that same shot but I moved back to where the original picture was taken:
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The picnic table looks deceptively small. I'm not sure why but it must have something to do with the angles or distance.

The antenna looks to be about 15.5 feet above ground (give or take a half foot for couplings and mounts). And it's about 3 feet into the ground.

I 'could' dig it deeper if I need to as I have plenty of height.

I do agree with you - that it's still too tall (I guess I should take off the two-foot section on top). I only put it there because I bought it for the TV antenna but I'm not sure if I can get 'any' signal pointing southwest in the Santa Cruz mountains.

Reply to
Chuck Banshee

I agree.

Conduit is what I'll use then.

OK. The logic (once I know it) is impeccable. Will do.

Wow. Very nice. I didn't know about lots of them, for example, HomeTech Solutions off of DeAnza. Wow. More than I ever knew. Lots better than Home Depot! :)

Reply to
Chuck Banshee

In hindsight, since that was 5 feet of drilling (most of it air, of course), between floors, conduit would have been a good idea.

That's good advice for next time!

Reply to
Chuck Banshee

Hopefully, someone who's done it will weigh in before it's officially declared a good idea. I suppose you'd cap the top of the conduit to keep most of the water and some of the critters out, or use two 90 degree fittings so that the Ethernet cable enters the conduit going up, over, and then down the length of the pole. Or something like that.

Reply to
Char Jackson

Argh. I've never seen it done by running the cables through the mast, even with a tilt up mast derrangement.

Drivel: This isn't a tilt over mast, but is kinda cool for keeping the antennas from digging a hole in the ground when lowered.

However, running coax up the center of a monopole for cellular service is standard procedure. The differnce is that the monopole is MUCH larger than the suggested water pipe mast. This offers easier access, additional support points, and less of a mess. Monopoles do have their problems, as these links illustrate:

The problems with running wires down the center of a mast are not very obvious:

  1. The top of the mast looked like a coax "fountain" with all the cables dripping out of the top in all directions. It was truely ugly.
  2. There is no way to secure the cables except at the top of the mast. The entire weight of the coax is supported only at the top. I would have expected the cables to stretch slightly. Instead, the sharp turn made by the coax cables going out the top caused the center conductor to cold flow through the dielectric, eventually shorting the cable.
  3. If the mast is tilt over, as is quite common, the cable out the bottom has to include a rather lenthy service loop. If you're going to secure it short pipe stub, you run the risk of cutting the cable if you lower the mast to the ground.

Bottom line: Lousy idea.

Reply to
Jeff Liebermann

We were talking about a vertical conduit, not the mast.

Single Ethernet cable in this case. When taken in context with the looks of the concrete base and the overall appearance of a water pipe mast, the level of beauty is not out of line.

Yes, there are ways to secure the cable but they haven't been discussed.

I haven't heard of any plans to tilt this mast.

You're probably right, even though each of your objections doesn't actually apply in this case.

Reply to
Char Jackson

I really recommend the right angle N. It makes it far less likely to break the wifi adapter. Incidentally, ALfa has a similar device called the tube.

Reply to
miso

Good point as the Bullet M2 is a cantilevered arm with all the force concentrated at the attachment point.

But, wouldn't a short N-female-to-N-male pigtail be even better (with the bullet tie-wrapped to the mast, for example)?

Reply to
Chuck Banshee

About the same as far as RF loss is concerned. Much worse if you consider water incursion. If you wrap the right angle connector, there will be no movement to break the waterproofing seal. However, with a pigtail, unless the M2 is properly secured to the panel antenna, it's gonna leak. If you're really careful to use a drip loop and plenty of slack, you might be able to secure the M2 to the mast, but I think the first time you move the mast, you're going to loose the seal.

Incidentally, my method of waterproofing is to mummify the connector using 1/2" or preferably 1" teflon pipe wrap. On top of that, apply a layer of 3M Scotch 33+ 7 mil electrical tape. All it does is hold the teflon tape in place. Spray with a thin coat of clear Krylon spray to make it UV proof.

Reply to
Jeff Liebermann

I had a temporary setup that got blown down by the wind. It was the one time I didn't use a pigtail. It smashed the Alfa 036H. The PCB has a bulge under the RPSMA connector. It also smells bad when powered up. I suspect it draws more than the allowed half an amp off the usb bus because the notebook was very unhappy booting up with the damaged unit attached.

I got the tube version. It is about $10 extra. No adapter required, i.e. it goes right to a N connector. [Like when did that become legal?] I use the elbow. I may mount the "tube" in a metal box just to make it more rugged. I find the tube version is slightly more sensitive than the 036H that Alfa sells. Not a big difference, but a step in the right direction.

It comes with a heavy usb cable of the "extension" flavor. I have a few real watertight feedthroughs I've got from junked NEMA boxes. I don't think the scheme alfa uses is really watertight on the USB side.

Anyway, a pigtail is probably more likely to fail than a right angle connector.

I don't suggest people purchase antennas with pigtails on them. That seems like a design destined to fail.

Reply to
miso

Photomast looks real Rube Goldberg. Just how expensive is a news van with telescoping mast?

In the photomast wmv file, it looks like they get it tilted up just in time before a car go barreling by.

My recollection is there are military antennas where the mast is the coax, so to speak. That is, support and RF feed are one item.

In any outdoor design, there is the school of "weep hole", and the school of watertight. Some people claim sealed units really aren't sealed, so whatever water does get in will eventually do damage. Hence they come up with a weep hole. The other school of thought is to seal everything up like a drum.

I bought an old NEMA box, which in theory is sealed, but noticed they stuffed it with desiccant packs.

Back to CAT5, I notice Moto Canopy setups leave the data cable exposed.

Come to think of it, I've seen some satellite hookups where the coax is in the LNB(F) support arm.

Reply to
miso

Dunno. Here's the MCI MMDS site survey van circa 2001:

I think it lasted about a week before it fell over.

I'm in the weep hole skool. My logic is that the only effective water seal is a pressurized box. Anything less will eventually leak water. So, unless it's hermetically sealed, and dry air pressurized, it needs a drain hole.

Yep. As long as the connector drains water out of the package, it will work. Gold on gold connectors won't rot. Maybe do it like the telcos and smear some silicon grease into the connector. Seems to work for the outdoor POTS NIU.

Yep. All of mine. The compression style F connector is a good water seal. (Note: Not all F connectors are suitable for outdoor use).

Reply to
Jeff Liebermann

Marine boxes are sealed and do a good job. We'd add a block of camphor before we closed them up and over near 40 years of working off shore never had a box leak (save ones that were mechanically damaged)

Reply to
NotMe

I suspect Jeff is closer to reality, though I don't doubt your boxes didn't leak. For electronics, just moisture in the air is enough. You would probably need a nitrogen purge and pressurization scheme for electronics. Some camera housings work that way.

Camphor fumes are to reduce rust. I don't know the chemistry behind this, so I don't know how effective this scheme is for electronics.

A weep hole doesn't keep out salt.

Fry's has the satellite F connectors. I'm not really impressed with the satellite coax they sell, though I use their patch cables for temporary setups.

Quad shielded coax has been at buzzword status for a while. Almost like drop forged. [Yeah, we dropped that wrench before shipping it to Harbor Freight.] Yeah, there are four shields. Not the greatest shields.....

Reply to
miso

Not nitrogen. Too expensive. Just dry air will work.

In a past life, I designed marine radios for Intech Inc. We learned quite a bit about water proofing. Much of it was learned the hard way. Most of my radios would work after the boards were soaked with a bucket of water. There's no magic there, just use low impedances for literally everything and fairly wide trace spacing. However, I had to also deal with vendor supplied SCADA hardware, which was full of dense PCB layout, high impedances, RF sensitive design, and other nightmares. Kinda like what you find in the typical consumer grade wireless router. The decision was made to not modify the design, but rather to protect the sensitive SCADA boards. I won't go into all the things that didn't work, but I will say that the only thing that worked every time was a pressurized box, vertically mounted boards (so that they drain) and dry air. To prevent condensation in case the dry air went away, there was a small heater to keep the temperature above the dew point. My idea of dry air was a bicycle pump with an air compressor dryer filter attached. Add a gauge, a desiccant cartridge, and the usual warning labels. If you think you can do better with other technology, you're welcome to try.

Dunno. Most of my stuff was aluminum. There are products that you can insert inside aluminum tubing (such as for hang gliders and antennas) that prevent internal corrosion. I don't know the chemistry offhand.

Actually, a weep hole has its place. If you can't pressurize with dry air, then you have to find a place for the water to escape. Water will eventually evaporate in temperate climates making a weep hole functional. However, puddling is very bad. That's why I mound the boards vertically (so they drain).

The absolute worst idea is somewhat sealed box, that's not pressurized. It works like a water pump. Water collects on the box seams. The sun comes up, heats up the box, causing some of the inside air to leak out. The sun goes down, the box cools off, and a partial vacuum is created inside the box. This sucks the water sitting on the seams into the box. The next day, the process is repeated. Eventually, there's quite a bit of water inside the box. It doesn't just sit on the bottom of the box. It evaporates when warm and condenses on the electronics. It's MUCH better if the water drain out the bottom after every cycle instead of being trapped inside.

I make my own CATV cables. The compression type of F connector is quite waterproof. I've also used it at 2.4Ghz. Works fine. You'll never notice the 50/75 ohm mismatch as the reflections are all lost in the high cable losses.

Quad shielded exists only because the FCC demanded that CATV leakage be very very very very low. The only thing that does that is quad shielded. If you have an ingress problem, use quad. Otherwise, double shielded (foil + braid) works just fine. My most irritating problem with RG6a/u is the unplated copper center conductor. It like to corrode, especially when the mating connector has tin plated contacts. I've been experimenting with electroless silver plating the copper, which seems to help.

Archived notes on corrosion by a real expert (not me).

Worth reading methinks.

Reply to
Jeff Liebermann

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