posted
Note I didn't say tripod "ON" a boat. We've used our tripod system for several years as we travel in our converted bus but last year when we bought a recreational trawler we had to get used to using tethered Blackberries for occasional internet access. The marine satellite internet systems are way out of our price range so that wasn't going to happen. This fall I started thinking about how it might be possible to use our existing tripod system from the boat. When we came home from Texas we brought a 300' spool of siamese coax with us and today we are tied to the remains of an old logging float 3/4 of the way up Howe Sound, completely out of cell coverage but online thanks to our Hughes tripod sitting on the shoreline. I've got a few wrinkles to work out of the system but if you can read this then its usable. I guess the next step is to use Don's utility to update our location.
posted
Sounds like a good plan. As long as you can put the tripod on a dock or beach or something similar you should not have any more issues than any other ground based user. 300' sounds like a lot of coax but as long as you get the signal you should be good to go!
-------------------- Bill Adams Winegard Company Posts: 15677 | From: Traveling the Western US | Registered: May 2003
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posted
Well to be honest, 300' plus the roughly 50' that was already on my LNB didn't work. I don't know for sure whether I had bad ends on the 300' extension or whether it was just simply too long. It hung up doing ACP after I did a force range - I forget exactly what the error message was but it sounded like it could be a cabling problem. I ended up cutting about 120' off, putting new ends on that and got online with roughly 175 feet total coax. Sometime when we need a longer run I'll try the balance of the 300' spool which should give me around 225'. I think even when we're anchored as long as I shore tie I can make that work by running the coax along the shore tie line.
If we can make it work its a whole new potential market for you resellers because the marine alternatives are wicked expen$$ive.
posted
I believe the system is designed to work with 100 meters (328 feet) max. A US version of the spec likely says 300 feet (to use round numbers). This does not leave room for less than perfect connections, etc., and frankly, you will need high quality / low loss coax. If you use about 250 feet of good stuff, you should have margin for a bit of loss in connections. Speaking of connections, they are going to get bad fast with salt water - best make sure they are well coated in lithium grease. It won't hurt to losen and tighten them a little at each new stop. Finally, the coax will absorb water over time if sitting in it. You need to make sure it's somehow suspended out of the water, and stored where it can dry out when not in use. Other than that, it should be no different than parking an RV on the beach! By the way, several people that have a home base dock berth actually mount a dish on a pole on the dock. They disconnect the coax and head out for the day, tie up and reconnect when they come back.
-------------------- Terrestrial Wireless (finally found an alternative!) Posts: 233 | Registered: May 2007
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posted
In my experience 300' of RG6 will never work. The loss is just too great. The signal loss really starts to add up for anything over 150'. I tried 185' once and the transmit side loss was too great to pass CP, and that was with a 4w transmitter. For distances over 150' you need to think of using RG11 coax, with lower signal loss per foot.
[ February 08, 2012, 11:47 AM: Message edited by: Don - Oregon ]
-------------------- Don Marr WWW.OREGONRV.NET 541-683-5361 See where I am Country Coach Concept 40' F1 - D3|7000s|99W|LinkSys wireless with 1000mw WiFi amp & Ext. antenna Posts: 3364 | From: Eugene, OR | Registered: Jun 2004
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posted
Not to be contradictory Don, but if you replace RG6 with RG8 you will actually lose power due to impedance mismatch, not to mention what it's doing to your transmitter by using a 50 ohm transmission line on a 75 ohm system. RG11 would achieve what you want, or even RG7, but RG8 is a very bad choice as a replacement in a system designed for RG6.
-------------------- Terrestrial Wireless (finally found an alternative!) Posts: 233 | Registered: May 2007
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posted
Oh dear - what hope is there for a simple fool such as myself if you experts can't agree?
So help me here - I need 75 ohm and lower loss than RG6 - correct? I'd really like to cobble together something that gives me a reliable connection at a minimum of 300' total coax. Consistently getting closer than that to shore is likely to cause other more serious problems - like running aground, poking holes in the bottom of the boat, etc. etc.
And I know about mounting a dish on the piling at the dock but we have this bad habit of wanting to use the boat so when we're onboard we tend to be somewhere other than at the dock.
posted
I have never heard of RG8 but looked it up and could not find any usable information. I know that if you use some RG11 quad shield you will be able to extend your connection over longer distances than would be available with RG6. When the first looked at the DirecWay system back in 2001 they recommended their installers use RG11 quad shield only. I still have some compression fitting in the van that won't fit anything else and will likely never use again!
-------------------- Bill Adams Winegard Company Posts: 15677 | From: Traveling the Western US | Registered: May 2003
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quote:Originally posted by No Alternative: Not to be contradictory Don, but if you replace RG6 with RG8 you will actually lose power due to impedance mismatch, not to mention what it's doing to your transmitter by using a 50 ohm transmission line on a 75 ohm system. RG11 would achieve what you want, or even RG7, but RG8 is a very bad choice as a replacement in a system designed for RG6.
you are right it was RG11 that I used a couple of years ago on that long run. The rec cable was functional with RG6 so I just needed the larger coax for the transmit side. With the RG6 on the transmit the signal was just barely under the minimum requirements, with the RG11 the signal was normal.
[ February 08, 2012, 10:16 AM: Message edited by: Don - Oregon ]
-------------------- Don Marr WWW.OREGONRV.NET 541-683-5361 See where I am Country Coach Concept 40' F1 - D3|7000s|99W|LinkSys wireless with 1000mw WiFi amp & Ext. antenna Posts: 3364 | From: Eugene, OR | Registered: Jun 2004
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posted
Bob, RG11 has a bit more than half the line-loss of RG6, so you can go almost twice as far.
Note: RG11a is not the same thing, and is high loss, so make sure it is RG11.
There really isn't another good choice. I've used RG-8 and the more modern LMR-400 with Cisco access points, but as noted they are 50-ohm and not suitable for use with our 75-ohm systems.
One of the reasons that 300 feet of RG-6 might work for someone and not for another is that they are on different L-Band transponder frequencies.
RG-6 has a loss of roughly 10dB/100 feet at 990MHz, but has a loss of 12dB/100 feet at 1410MHz. That is a significant difference - more than 50% greater loss from that 2dB change.
posted
This forum is such a wonderful resource. Thank you guys.
Here's the location in question:
Its an old logging float about 2/3 of the way up Howe Sound. We came up here looking for a runaway bluenoser that hangs out here for the winter. He's got his work-in-progress homebuilt sailboat side tied across the float from us. We stayed a few extra days because he doesn't have a generator so he is really appreciating our Onan (which has blessedly decided to work this week). Once I get the 300 foot thing figured out I'll post from some really great locations but this one isn't too shabby a view.
posted
You might consider moving your modem to the antenna location and using CAT 5 cable-- Good to 100 meters or so--
Power requirement is relatively low for the modem and xmtr-- Maybe too much for POE but easily doable with a small gauge ac cable--
Edit-- I see standard POE good to 13watts and POE plus to 25 watts so there may be a way if you do a bit of research-- (I know the power supply is rated higher but what is the actual measured draw of the system?)
ReM
[ February 08, 2012, 12:46 PM: Message edited by: ReM ]
posted
You would need a watertight encloser for the modem, perhaps a modified Pelican case would work. Having it remain watertight and yet breath would be the issue.
-------------------- Don Marr WWW.OREGONRV.NET 541-683-5361 See where I am Country Coach Concept 40' F1 - D3|7000s|99W|LinkSys wireless with 1000mw WiFi amp & Ext. antenna Posts: 3364 | From: Eugene, OR | Registered: Jun 2004
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quote:Originally posted by Don - Oregon: You would need a watertight encloser for the modem, perhaps a modified Pelican case would work. Having it remain watertight and yet breath would be the issue.
That's part of the reason why I haven't gone that way and why I want to avoid going there. If I can get 300' with coax then there's no big gain by using Cat 5. In addition to keeping the modem dry there's the whole issue of transporting 110V power to shore. Obviously that can be done but I think the risk of water intrusion to the coax is less than the risk of AC power and salt water. On balance I don't think there's one perfect solution but keep the suggestions coming. Boating in the Pacific North Wet means that you have to boat in the rain and today it has been absolutely pissing down. A great day to have a good furnace, a dry boat and an internet connection.
posted
beautiful country up there - i came down highway 99 from lillooet to vancouver, which hugs the opposite shore of the sound, and vowed to come back some day.
i hear you on the problems with maintaining a tripod rig in a marine environment. due to mrs. campskunk's preferences for camping location, mine has been in salt spray all down the pacific coast highway and here in FL for four of the last six months. i'm finding all the parts, no matter how small, that aren't stainless or aluminum. i fabricated new thumbscrews out of stainless hardware with molded epoxy knobs - the old galvanized stuff that came with the dish attached itself solidly to the threads in the stand body when i left it set up for two weeks plus on the oregon coast. almost all the knobs broke off in the process of disassembling it.
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