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rar110
29th December 2008, 09:25 PM
Hi,

I recently received a Icom 440 for my birthday and an RFI CD5000 for christmas (to fit to the 110). (I currently have a single battery set up).

I was intending on locating the ICOM 440 inside the center console and the arial on the bar.

Should I connect the power via the ignition or direct to the battery?

Will I get better reception if I mount it at the bullbar or from an FFR (army fitted for radio) mount at the rear just above the filler point?

thanks

Peter

weeds
29th December 2008, 09:31 PM
mine is connect direct to the battery...i like to be able to have the uhf turned on with the ignition turned off


bullbar i would think, if you use a FFR mount your arial will be hitting you cab all the time

d@rk51d3
29th December 2008, 09:34 PM
Antenna position will probably have a similar effect either way. If you get one that is ground plane independent, I won't matter a great deal where you put it.

As for wiring, I generally run direct from the battery, with some fuses along the way. At least you wont need to leave the ignition on to use the radio.

If you forget to turn it off though, you can wind up with a dead battery. At least running through the ignition switch should save you there (usually).


A bit of a "catch 22" I'm afraid.

Sleepy
29th December 2008, 09:37 PM
Hi,

I recently received a Icom 440 for my birthday and an RFI CD5000 for my birthday (the 110). (I currently have a single battery set up).

I was intending on locating the ICOM 440 inside the center console and the arial on the bar.

Should I connect the power via the ignition or direct to the battery?

Will I get better reception if I mount it at the bullbar or from an FFR (army fitted for radio) mount at the rear just above the filler point?

thanks

Peter

G'day Peter

Some prefer ignition so that you don't accidently leave it on and drain the battery. I don't think you will introduce much intereference through the ignition. I would go straight to the battery. It is pretty simple from the centre box - don't forget an in-line fuse.

Being UHF the mounting won't make a huge difference - I would go for the simplest option. (The best spot for propagation is the centre of the roof! But not a popular option.) .

dmdigital
29th December 2008, 09:38 PM
The CD5000 is ground plane independent so won't mater being on the bullbar. I to wire UHF direct to battery. Think about where to mount the base unit as with the extension lead you can put in anywhere in the 110 and still have the handset next to you. If you want to raise the cubby up a little then it would fit underneath quiet nicely.

Xavie
30th December 2008, 05:30 AM
The ICOM units are designed to be connected to the battery according to the instruction manual I have.. Of course it is an issue if you leave it on and I have done it many times over night:eek: but luckily has not drained my battery to much.

amtravic1
30th December 2008, 05:41 AM
Dont know about the 440 but the Icom 400 can be set to switch itself off if left unattended after a period of time. Perhaps check the manual for the 440 however I dont think it is a problem wiring directly as it would probably take at least 3 days to flatten a battery to the point where you could not start the car if you have a decent battery.

Ian

dmdigital
30th December 2008, 05:46 AM
Battery drain from a CB UHF is minimal when left on, even when receiving. In the case of the IC-440 its listed as Rx (standby) 400mA and Rx (max audio) 1500mA.

weeds
30th December 2008, 05:49 AM
Current drain : (at 13.8V/27.6V, approx. ) with HM-182 Tx 5W 2000mA/1200mA Rx Max. audio 1500mA/1000mA Standby 400mA/250mA

weeds
30th December 2008, 05:50 AM
oops.....great minds think alike

JDNSW
30th December 2008, 07:44 AM
I have tried both direct from battery and via ignition. No difference in performance, but I have had flat batteries on quite a few occasions as a result, particularly with vehicles that are not regularly used. My 2a is now wired both ways - with a changeover switch so you can switch on the radio with the ignition off only when you really need to, but normally leave it on the ignition position.

John

d@rk51d3
30th December 2008, 07:47 AM
I have tried both direct from battery and via ignition. No difference in performance, but I have had flat batteries on quite a few occasions as a result, particularly with vehicles that are not regularly used. My 2a is now wired both ways - with a changeover switch so you can switch on the radio with the ignition off only when you really need to, but normally leave it on the ignition position.

John


Speaking of 2a's, are there any positive earth UHF sets around? I guess it's probably easier to convert the vehicle to neg earth.

waynep
30th December 2008, 07:57 AM
Battery drain from a CB UHF is minimal when left on, even when receiving. In the case of the IC-440 its listed as Rx (standby) 400mA and Rx (max audio) 1500mA.

Of course, the current will increase quite a bit whenever you transmit. Sometimes if you tap off an iginitio switched wiring, the wiring will not be heavy enough, and the voltage at the radio will drop when you transmit. This will cause a drop in transmit power or possibly even distorted transmissions.

If you really wanted the radio to go off and on with the ignition, I'd be suggesting you still wire the radio power direct to the battery but switch it via a relay from the ignition. ( similar to the setup for driving lights. )

Some UHF sets have an "ignition sense" wire that is basically does the same thing.

waynep
30th December 2008, 07:59 AM
Battery drain from a CB UHF is minimal when left on, even when receiving. In the case of the IC-440 its listed as Rx (standby) 400mA and Rx (max audio) 1500mA.

Of course, the current will also increase quite a bit whenever you transmit. ( I see for the IC-440 Tx current draw is listed as 2 amps which is better than the old 400 which was spec'd at 4 amps ).

Sometimes if you run the radio off an iginition switched wire, the car's wiring will not be heavy enough, and the voltage at the radio will drop when you transmit. This may cause a drop in transmit power. It would be hard to detect unless you put a power meter in the antenna line, but it would reduce your range a bit. ( sometimes might cause distortion or buzzing on your transmission too ).

Some UHF sets have an "ignition sense" wire that means you can wire the main power lead to the battery but switch the radio off from the ignition. The old 400 had this option via the accesory connector, I am presuming the 440 has it too.

rar110
30th December 2008, 06:06 PM
great advice as usual. thanks fellas.

dmdigital
30th December 2008, 06:46 PM
If you really wanted the radio to go off and on with the ignition, I'd be suggesting you still wire the radio power direct to the battery but switch it via a relay from the ignition. ( similar to the setup for driving lights. )
Always on the list of things to do but I never get around to it.