GMRS installation

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5280Ranger

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I picked up the MXT275 kit for my Ranger. I will be installing it sometime next week (hopefully). For power, the manual says to run it to a fuse. I like that idea, because I can run it inside the cab and not have to worry about breaking through the firewall. That being said, if direct to the battery is better, I don't mind.

What is the best practice for wiring up the radio? I'd prefer to have power switched, so I don't accidentally leave it on, but I can deal with direct power.

Thanks!
 

Sparksalot

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Definitely go straight to the battery. You’ll have less chance of noise induced through the power cable,plus your battery will act as a filter itself. Be absolutely sure to put an inline fuse in, as close as practical to the battery.
 

5280Ranger

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Definitely go straight to the battery. You’ll have less chance of noise induced through the power cable,plus your battery will act as a filter itself. Be absolutely sure to put an inline fuse in, as close as practical to the battery.
That’s what I wanted to know. Thanks!
 
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Sparksalot

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Good luck with your install. How are you planning to mount the antenna?
 

Prerunner1982

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The radio draws so little on receive that if you left it on and your battery dies overnight you have other issues.
As Rex said, direct to the battery is the best option.
Also you will need a different antenna to use with that hood lip mount, the ghost antenna is popular.
 

Sparksalot

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I have the magnet mount that came with the kit and this hood mount. I am not sure yet. I will update when installed.
Something to be aware of with a hood lip mount, or any hard mount really, is you will need to have metal to metal contact for the antenna to work properly. That mount looks like the screws will bite and provide it.
 

5280Ranger

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The radio draws so little on receive that if you left it on and your battery dies overnight you have other issues.
As Rex said, direct to the battery is the best option.
Also you will need a different antenna to use with that hood lip mount, the ghost antenna is popular.
I got the kit that is the ghost antenna in it. The price is really good for all the pieces that come with it. I’ll post up when I open it.
 

trail_runn4r

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Something to be aware of with a hood lip mount, or any hard mount really, is you will need to have metal to metal contact for the antenna to work properly. That mount looks like the screws will bite and provide it.
I have the lip mount and the 3db ghost antenna but I have installed it with some rubber padding so that it won't ruin the paint.... then another member pointed out that I needed metal to metal (lol thanks @Neal A. Tew) and it definitely works a bit better now.
 

TheBison

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I install radios in vehicles for a living (like police and fire vehicle radios). Definitely agree with what everyone has said about going direct to the battery, for the reasons they list plus many more (modern vehicle fuse blocks don't like tap-a-circuits for much more than an "ignition sense" ) and fuse blocks are easily overloaded with two-way radios they weren't designed for. If a radio isn't power switched (some have a 3rd wire besides "hot" and "return" that goes to a switched circuit) you can add a relay that's switched by a low-current tap into your passenger compartment fuse block to turn it on and off with the accessories. If you're concerned about getting through the firewall, I've found that almost all vehicles have plastic or rubber grommets located throughout the cab (under the carpeting) that are easy to drill through for wiring and you can just silicone them to seal them.

So, here's how I'd do it: run the main "hot" or positive cable through the body via an existing accessible plastic or rubber plug to the battery, adding an appropriate inline fuse as close to the battery terminal as possible. You can terminate the "return" or negative cable inside the cab - put a ring terminal on it and go to a seat bolt etc. or if you look around the passenger compartment fuse block there's usually a ground stud that lots of other black "negative" wires are tapped to from the factory electronics - no need to get another wire all the way up to the battery. Find a circuit in the fuse block that you can add a tap-a-circuit to (use a multimeter to check for a circuit that is dead when the accessories are off but hot when the accessories are on) and use that as the "trigger" for a 12 V relay spliced into your radio's power connection to turn it on and off with the ignition. It's super simple but if you need it sketched out just holler!
 

OTH Overland

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I agree with Bison's comments above, especially with newer vehicles that have canbus or similar systems linking all the computers together I like to keep all radios and other electronic gizmos as separate from the vehicle systems as possible to reduce interference, and allow me to shut down all accessory items leaving the vehicle systems stock if something goes wrong. I have installed a pair of power distribution bars inside my center console, and feed them directly from the positive and negative battery posts with a large fuse on the positive wire at the battery in case the wire gets damaged or shorted to ground. Then any inside accessory can be connected at that point (with an appropriately sized fuse for what it is feeding) without having to run separate wires through the firewall for each accessory. Also I feel it provides a better ground path by not using chassis ground. I have several high power radios in my rigs, so I have installed large gauge wire to the feeders to avoid voltage drop and overloading. I also install a heavy duty relay installed in the positive feeder to allow me to power down all the radios with one low amperage switch. I am controlling the relay from my switch-pros SP-9100 programable switch control system. I have the switch programmed with an adjustable delay off so I can listen to the radios with the truck off, but they will still auto shut off after a while. also don't have to switch them all off separately each time I get out of the rig. A bit overkill for just one radio, but then again all radio collections started out with just one. .lol

View attachment 201203
 

5280Ranger

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I have the lip mount and the 3db ghost antenna but I have installed it with some rubber padding so that it won't ruin the paint.... then another member pointed out that I needed metal to metal (lol thanks @Neal A. Tew) and it definitely works a bit better now.
That's good to know. I was actually worried about driving those screws into the hood, but it sounds like that's the way to go.

I install radios in vehicles for a living (like police and fire vehicle radios). Definitely agree with what everyone has said about going direct to the battery, for the reasons they list plus many more (modern vehicle fuse blocks don't like tap-a-circuits for much more than an "ignition sense" ) and fuse blocks are easily overloaded with two-way radios they weren't designed for. If a radio isn't power switched (some have a 3rd wire besides "hot" and "return" that goes to a switched circuit) you can add a relay that's switched by a low-current tap into your passenger compartment fuse block to turn it on and off with the accessories. If you're concerned about getting through the firewall, I've found that almost all vehicles have plastic or rubber grommets located throughout the cab (under the carpeting) that are easy to drill through for wiring and you can just silicone them to seal them.

So, here's how I'd do it: run the main "hot" or positive cable through the body via an existing accessible plastic or rubber plug to the battery, adding an appropriate inline fuse as close to the battery terminal as possible. You can terminate the "return" or negative cable inside the cab - put a ring terminal on it and go to a seat bolt etc. or if you look around the passenger compartment fuse block there's usually a ground stud that lots of other black "negative" wires are tapped to from the factory electronics - no need to get another wire all the way up to the battery. Find a circuit in the fuse block that you can add a tap-a-circuit to (use a multimeter to check for a circuit that is dead when the accessories are off but hot when the accessories are on) and use that as the "trigger" for a 12 V relay spliced into your radio's power connection to turn it on and off with the ignition. It's super simple but if you need it sketched out just holler!
Thanks for the 'how-to'! You're a couple hours from me, but maybe you'd be interested in lending a hand with the install (no pressure, I don't want to do my job when I am not working)... I'm good with mechanical stuff (usually) but electrical makes me real nervous. Fires and such.

I agree with Bison's comments above, especially with newer vehicles that have canbus or similar systems linking all the computers together I like to keep all radios and other electronic gizmos as separate from the vehicle systems as possible to reduce interference, and allow me to shut down all accessory items leaving the vehicle systems stock if something goes wrong. I have installed a pair of power distribution bars inside my center console, and feed them directly from the positive and negative battery posts with a large fuse on the positive wire at the battery in case the wire gets damaged or shorted to ground. Then any inside accessory can be connected at that point (with an appropriately sized fuse for what it is feeding) without having to run separate wires through the firewall for each accessory. Also I feel it provides a better ground path by not using chassis ground. I have several high power radios in my rigs, so I have installed large gauge wire to the feeders to avoid voltage drop and overloading. I also install a heavy duty relay installed in the positive feeder to allow me to power down all the radios with one low amperage switch. I am controlling the relay from my switch-pros SP-9100 programable switch control system. I have the switch programmed with an adjustable delay off so I can listen to the radios with the truck off, but they will still auto shut off after a while. also don't have to switch them all off separately each time I get out of the rig. A bit overkill for just one radio, but then again all radio collections started out with just one. .lol
Thank you for the insight, I really appreciate it. I have thought about running a direct power fuse block in to the cab and then going from there. I'll have to see what my needs are. I've been intrigued by the accessory switches that are Bluetooth from the cab, so you don't have to breach the firewall, though that wouldn't help this installation.
 

M Rose

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That's good to know. I was actually worried about driving those screws into the hood, but it sounds like that's the way to go.



Thanks for the 'how-to'! You're a couple hours from me, but maybe you'd be interested in lending a hand with the install (no pressure, I don't want to do my job when I am not working)... I'm good with mechanical stuff (usually) but electrical makes me real nervous. Fires and such.



Thank you for the insight, I really appreciate it. I have thought about running a direct power fuse block in to the cab and then going from there. I'll have to see what my needs are. I've been intrigued by the accessory switches that are Bluetooth from the cab, so you don't have to breach the firewall, though that wouldn't help this installation.
If you are going to run a dedicated fuse block into the cab, you still want to isolate your comms circuits straight to the battery. LED lights, fridges, and cheap inverters cause RF to back feed into the receiver and cause a whine. You want your radio circuit isolated from all the other circuits, hence wiring straight to the battery is recommended.
 
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5280Ranger

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I did get the radio installed. I wired it directly to the battery and was able to test it out. It worked flawlessly. Thank you for the recommendations. I have pictures in my build thread, but I am going to take some better pictures (a bit more detailed) and post them here. The hardest part was getting wiring to the engine bay. I tried the firewall grommet and had no success. The engine bay is *real* tight in the Ranger. I ended up poking a hole through the drain plug in the passenger's side floorboard and using some silicon sealer to seal it up. Time will tell if it leaks, but I am really hoping not...

I ordered some pieces from Bullet Point to mount the handset, as the sticky mount Midland provides failed after a couple days. I don't want to futz with it, so a mounting arm and clip has been ordered. I have the Built Right Industries dash mount installed already, so now we wait for parts.
 
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reaver

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If you are going to run a dedicated fuse block into the cab, you still want to isolate your comms circuits straight to the battery. LED lights, fridges, and cheap inverters cause RF to back feed into the receiver and cause a whine. You want your radio circuit isolated from all the other circuits, hence wiring straight to the battery is recommended.
I realize this is probably best practice, but when you helped me with my aux electrical system, we ran it from the secondary fuse block.

I've not noticed any noise in real world use so far.

I did get the radio installed. I wired it directly to the battery and was able to test it out. It worked flawlessly. Thank you for the recommendations. I have pictures in my build thread, but I am going to take some better pictures (a bit more detailed) and post them here. The hardest part was getting wiring to the engine bay. I tried the firewall grommet and had no success. The engine bay is *real* tight in the Ranger. I ended up poking a hole through the drain plug in the passenger's side floorboard and using some silicon sealer to seal it up. Time will tell if it leaks, but I am really hoping not...

I ordered some pieces from Bullet Point to mount the handset, as the sticky mount Midland provides failed after a couple days. I don't want to futz with it, so a mounting arm and clip has been ordered. I have the Built Right Industries dash mount installed already, so now we wait for parts.
Congrats on the 275! It's a great radio, and you'll be very happy with it. I have one in each rig.
 
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LONO100

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I picked up the MXT275 kit for my Ranger. I will be installing it sometime next week (hopefully). For power, the manual says to run it to a fuse. I like that idea, because I can run it inside the cab and not have to worry about breaking through the firewall. That being said, if direct to the battery is better, I don't mind.

What is the best practice for wiring up the radio? I'd prefer to have power switched, so I don't accidentally leave it on, but I can deal with direct power.

Thanks!
The best way to hook that up is to take the time to go through the firewall and connect directly to the battery. This will give you the cleanest connection and power which is important if you want to optimize radio performance. Make sure to buy a little inline fuse holder that you can run on the positive wire and then conmect that to the battery by crimping the appropriate size ring terminal. Use the recommended fuse, that should be in the install manual. Also make sure your ground is solid and secured. A loose ground will give you inconsistent performance. Hope this helps.
 

M Rose

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I realize this is probably best practice, but when you helped me with my aux electrical system, we ran it from the secondary fuse block.

I've not noticed any noise in real world use so far.


Congrats on the 275! It's a great radio, and you'll be very happy with it. I have one in each rig.
Yes we ran it to your aux system… hooked up strait to the battery…your radio is still isolated from the RF generating things… if you add LED lights in the future we might have to look into rewriting your radio… but until then we are fine.
 

ptgarcia

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I recently rewired all the accessories on my truck and installed a Blue Sea Systems fuse block. Using 4 awg I connected it directly too one of my starter batteries (I have two in my Cummins Ram), then connected my radio and LED lights to the fuse block. So far, I have no noise or interference in my old Icom IC-V8000 radio.