Using pre-wired satellite cable for 50 ohm cell booster

[Joetiii]

I am installing a cellular signal booster in my 2015 Itasca Cambria and dread the thought of having to pull the 50 ohm cable through the walls from front of the rig to the fridge vent in the roof. Another easier option I am considering is to use the 75 ohm cable for the external satellite that already runs front to back. I then can use some adapters to connect the different ends and run the cable up through the rear radio antenna hole.

I am looking to hear if anybody has done this successfully?

I have read that there is some signal loss when combining the two different cables, but not sure if it affects performance all that much. Thoughts?

TIA

Joe

[BobC]

I haven't done this with a cell booster but I am a Ham (amateur radio operator) and have had to deal with many similar problems. As you probably know, you can buy impedance matching connectors. Here's one:

https://www.amazon.com/Connector-Con...3688463&sr=8-3

It may work without converters. You'll have a larger "standing wave ratio" than the ideal 1:1 ratio but, if your signal booster's antenna is good, the difference may not be significant. One person may tell you they tried it and it worked fine while another may have had problems. It all depends on their specific cable length, something known as the "velocity factor" of their cable and the equipment being used. This link will give you an idea of what's involved:

https://www.amazon.com/Connector-Con...3688463&sr=8-3

Trying it without converters won't hurt anything. If it doesn't work effectively enough, you'll have to use convertors. If I understand your setup, I think you'll need two convertors, one at each end of the 75 ohm cable. Even with the convertors, there will be some signal loss but it shouldn't be a problem.

[creativepart]

Back when I installed a Weboost Drive 4G-X (6+ years ago) I inquired about the same thing. Weboost tech support said not to do it. That the power loss would be so great that it would be the same as having no antenna at all.

First, there was the 75ohm conversion and next there was the cable loss with RG59 75 ohm F-Type Coaxial Cable (Sat Dish cable). Also, each connector/splitter robs more of the signal strength.

I have to admit, I did not try it. I just took their advice and directly wired SMA cable/antenna without any adapters or extra connectors.

But, if you search around you'll find that newer 4g/5g gear uses 2, 4, 6 or even 8 antennas and operates on multiple frequencies simultaneously unlike previous 3G and early 4G devices which used a single antenna and channel. Boosters are much less beneficial with current cellular devices and mostly a thing of the past these days.

[Joetiii]

Thanks Bob. I did see some posts that show guys replacing their speakers and there seems to be a little space to pull a wire through. If I can snake the cable through, that would be best. But those connectors would seem to work for me, though the outdoor antenna input is not a standard N type female. The SureCall Antennas appear to have a reverse polarity TNC female. I will search Amazon and see what they have that might do the trick.

[BobC]

Originally Posted by Joetiii

But those connectors would seem to work for me, though the outdoor antenna input is not a standard N type female. The SureCall Antennas appear to have a reverse polarity TNC female. I will search Amazon and see what they have that might do the trick.

There's always something to make things more difficult than they have to be. I have wall wort power supplies with a positive center pin (standard) in the connector and some with a negative center pin in the connector. Go figure.

[kvmllr]

I mounted our WeBoost antenna on the top of the ladder on our 3235 Voyage. I ran the cable through the slide seal to the booster. I wish the "pre-wired for wifi" would have been an actual link to an antenna cable.

[dtrower]

I mounted the Weboost Destination RV Booster in my 2014 Winnebago Tour and used the prewired satellite connector. The cables and connections were all exactly the same. We move approximately every two weeks and like not having to slide the cable through the slideout seals. I do not feel I lose any performance as the booster works extremely well.

[Bosse]

The cellular booster simply wants separation between the (primary) antenna that “connects” with the cell towers and the (secondary) antenna which “connects” with your devices. The greater the separation, the better. The primary should be a position with the least amount of obstructions to the cell tower. The secondary should service the interior of the MH, and could be installed indoors. However, since glass attenuates radio signals very little, you could locate it outside a window too. If both antennas are outdoors, you don’t have to worry about penetrating the “shell” of the MH! Just run the secondary cable back out via the fridge vent and route it on the outside. (Also ham, NO2W)

[Shedboy]

Originally Posted by BobC

I haven't done this with a cell booster but I am a Ham (amateur radio operator) and have had to deal with many similar problems. As you probably know, you can buy impedance matching connectors. Here's one:

https://www.amazon.com/Connector-Con...3688463&sr=8-3

It may work without converters. You'll have a larger "standing wave ratio" than the ideal 1:1 ratio but, if your signal booster's antenna is good, the difference may not be significant. One person may tell you they tried it and it worked fine while another may have had problems. It all depends on their specific cable length, something known as the "velocity factor" of their cable and the equipment being used. This link will give you an idea of what's involved:

https://www.amazon.com/Connector-Con...3688463&sr=8-3

Trying it without converters won't hurt anything. If it doesn't work effectively enough, you'll have to use convertors. If I understand your setup, I think you'll need two convertors, one at each end of the 75 ohm cable. Even with the convertors, there will be some signal loss but it shouldn't be a problem.

Agree completely - in a "pure" theoretical system 75 to 50 ohm transition yields a 1.5 SWR (standing wave ratio) - roughly a reflection coefficient of 20% and a power loss of 4%. Where does the 20% go? It is re-radiated in the coax feed line.


There are many other loss variables that override the known feed line impedance mismatch, 1. what frequency? 2. insertion loss of impedance matching devices 3. insertion loss of coax and added coax connectors.



Nothing ventured, nothing gained, there is no penalty for hooking it up as is, except any expense and time, nothing will be electrically damaged.

[Joetiii]

Originally Posted by Shedboy

Agree completely - in a "pure" theoretical system 75 to 50 ohm transition yields a 1.5 SWR (standing wave ratio) - roughly a reflection coefficient of 20% and a power loss of 4%. Where does the 20% go? It is re-radiated in the coax feed line.


There are many other loss variables that override the known feed line impedance mismatch, 1. what frequency? 2. insertion loss of impedance matching devices 3. insertion loss of coax and added coax connectors.



Nothing ventured, nothing gained, there is no penalty for hooking it up as is, except any expense and time, nothing will be electrically damaged.

Thanks, you guys, you have probably forgotten more than I'll ever know.

Anyway, a followup question..... my booster came with 40 ft of SC240 low loss cable with terminated ends on it. Since I will not need all that length, is it best to coil it up and Hideaway in my rig? Or should I cut to length once I know it works well and reterminate with the appropriate FME female?

That being said, can I use an F Type male to reterminate?