Thread: UHF Radio Mounting

Originally Posted by HarryO

Admin - posted this but it disappeared - please delete if duplicate.

Hi All

A solution and a question.

Solution

I read the many posts about mounting UHF Radios with controls in the hand piece and did not really like them. Finally settled on mounting the Radio under the dash below the steering wheel.

If you look where the steering column goes through the bulkhead there are a few “available” studs - Only needed to welded up a 90deg T Mounting Bracket and bolt onto the stud.



Question
I want the Radio to turn on/off based on the RJ45 plug for the hand piece being plugged in/out. Has anyone come up with a wizz bang solution for this?

That’s a brilliant solution. Thanks, I need to mount mine also.

Why not turn it on and off with the power supply via a relay like everyone else?

Hi John

I want to wire it to the Aux Battery and guaranteed I will forget to turn it off.

This way it can be turn on while parked - and can be used without the ignition being turned on (and its pesky timeout).

Cheers

Hey Harry,

Just to get your scope clear. You want the power to come on when you plug the RJ into the bulk head and power off?

I think I have come up with something but just need to clarify it and draw the circuit

Originally Posted by HarryO

Hi John

I want to wire it to the Aux Battery and guaranteed I will forget to turn it off.

This way it can be turn on while parked - and can be used without the ignition being turned on (and its pesky timeout).

Cheers

One option to consider with the D4 is running the power via a relay which is triggered off the battery saver relay by adding a fuse tap to fuse 57 in the central junction box.

When the ignition is off this should stay powered up for 15 minutes after you turn off the ignition, or for 15 mins when ever you open a door (timer restarts every time you open a door).

It should also stayed powered up when the ignition is on.

Note: different for the D3. Need to tap the power supply to the glove box lamp directly.

I have not tried this yet myself but considering it for powering an android head unit myself.

Originally Posted by HarryO

Hi John

I want to wire it to the Aux Battery and guaranteed I will forget to turn it off.

This way it can be turn on while parked - and can be used without the ignition being turned on (and its pesky timeout).

Cheers

Like Josh asked, power it via aux battery and have it only powering up when you plug in the rj45 and off when you unplug the rj45?

Realistically, if the radio you've chosen doesn't have this function (I don't know of any at all) then building it is going to be much more work than its really worth.

Would having a switch on the dash work for you? In the end you'd have to remember to unplug the cable still with your desired solution and that's a crap spot to have to lean down to.

If I was to do it and retain the function you want (ie. Having the radio on when the ignition is on, but also having the option of using it when the ignition is off), then I would use a SPST NO relay. Have it's common terminal connected to your auxillary battery as the power source. Connect an ignition switched power source to the coil terminal to energise it while the ignition is on and also connect that coil terminal back to a SPST switch that is connected directly to a battery.

Essentially, if the ignition is off then you would flick the switch on, that would energise the relay and turn the radio on.

You could also just run without a relay using a DPST switch, but the relay is a more elegant, possibly safer (depending on the load and the switch used) solution.

I can draw it up properly tomorrow if need be.

Thanks for all the responses.


John & Josh that was the idea but when Chris put it like that he’s right - remembering to unplug it is as much hassle as remembering to turn it off! The thing that irritates me is the time-out on the ignition.


What I want is the UHF radio to stay on for about an hour or two after the ignition turns off (or switch toggled) so very similar to what Chris suggested. I will work something out with a SPDT delay off timer.


Chris - The Mic plug is not going to be all the way down there. It’s going to be run via an extension to a bulkhead RJ45 connector on the dash. No need to bend down - easy to access.