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Getting a signal through metal walls?


GXExplorer

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Is there a signal booster similar to the WeBoost but for GMRS frequencies? I know that I could connect an external antenna outside then use an adapter to connect the coax to my handheld. But, I don't want to be tethered to a cable with a handheld so that I can RX and TX anywhere within my mobile home. My home is clad with metal on the exterior walls and on the roof.

 

Thanks.

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You could build a low power repeater. Problem will be you will need an indoor and outdoor antenna. When the repeater transmitting. You will lose half of the power to each antenna. Plus a mess of other things that could go wrong.

I had looked at passive repeaters/antennas. But the usefulness of them are low. In your case. I would investigate this an option. Don't expect much, but to spend money. You could try to build a dipole indoors connected to a yagi outside pointed at the area of intrest. But again passive repeaters aren't in high use for a reason.

Another option is to get a kg100g, or any radio with a Bluetooth option. With a Bluetooth mic and connect the kg to an external antenna.

For hams, I have contemplated buy a uv578 with Bluetooth head control mic. But always just walk over to one of my digital radios and use the hotspot. Haven't seen a gmrs (tuned) hotspot yet. Guess that will be on a to do list.

Sent from my SM-S901U using Tapatalk

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Yes, there are devices like what you are describing, however, the cost associated with them isn't what most people would consider reasonable. 

A typical DAS (distributed antenna system amplifier, known as a BDA or BI-directional amplifier for UHF frequencies is going to cost around 15 to 18 THOUSAND dollars.

This equipment is meant for providing coverage to public safety personnel when in a building responding to a call for service at the facility.

 

So what are other REASONABLE options for you and your situation that don't cost more than a decent used car?

First would be a base station radio with an external antenna.  This can be connected to a Zello interface that can be used with your phone and the Zello app.

This of course will work anywhere your phone will work if the computer interface is connected to the Internet.  Obviously your phone with need either carrier signal or be attached to the Internet wirelessly, but it's a workable solution.

A set up from that would be a Radio-Pro interface from CTI products.  Coupled to a MotoTRBO radio, the phone app that works with this interface will add the ability to select channels on the radio remotely.  This is not exactly cheap however.  So I would be looking to find a used interface and hope it works.  These interfaces typically come with a SINGLE license for the phone app so it would be a single connection sort of thing.  Again, completely workable solution.  I have this as well as Zello on a control station as a backup.  Both work fine.  Both are LEGAL methods of doing what you are talking about.

From here it gets into the sketchy stuff from a federal regulation standpoint.

NONE OF THIS IS SUGGESTED, while it's a technically workable solution, it runs afoul of regulations pertaining to radio communications.

First would be a dual band radio with an outdoor antenna with crossband ability. VHF-UHF and a VHF portable radio for communications to the cross band repeater where the cross band radio is programmed for the repeater on one channel and the other channel programmed simplex to communicate to the portable radio.

Second would be a set of back to back radios that did the same thing as the dual band radio.  Again, if you go this route, turn the power DOWN all the way on the VHF radio to eliminate (or close to it) the signal getting outside the building on the VHF side. 

 

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If you have a strong signal outside those metal walls - a passive repeater (just 2 antennas hooked together as described above by kidphc) is a workable solution. I usually tell people that a passive antenna system will fix a small problem in a small area.

You use an outdoor Yagi directional antenna pointed towards the repeater site, along with LOW loss (Heliax hardline is your friend for this type of setup) cable with the fewest possible connectors. Any loss is more loss than you want. Then install and connect an interior antenna in the center of the room/area where you need signal the most.  The antenna system acts as a conduit/pipeline for the signal - both incoming and outgoing... thus the passive repeater nickname. Plus, that sounds more exotic than "I'm gonna screw 2 antennas together back to back".

I've done setups like this for job trailers or basement offices, and while I tell the customer they can expect portable coverage within 8-10 feet of the interior antenna, they usually do better than double that. You should have an outdoor signal level above -85 dBm for this type of setup to work. Stronger levels are better, but if the signal level was that strong outside, you probably wouldn't be having the issue inside.

 

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