Cost Efficient Mobile Antennae?

[krnlpanick]

So I was just assigned an EFJ RS-3500 mobile unit and I need to figure out a couple items, including the best antennae for my money.

I have seen a few mentions of different antennae on here but figure it would help to illustrate my situation. I currently drive an Audi A4. So I want the antennae to be somewhat discreet (ie I don't want a huge antennae) but I also want it to be effective.

Also, there is the question of mounting it. My stock head unit in the Audi went out and I haven't replaced it yet, so I am now thinking of mounting both the EFJ and a new single-din head unit in the dash where the double-din head unit used to be. The only concern I have with this is heat. Is heat a factor on these radios?

I think I have a good plan for all the wiring figured out (if you aren't familiar, Audi wiring, especially audio wiring is not exactly intuitive to understand)

So, thoughts?

[denverpilot]

They shut down when overheated, sometimes just after they blow their final amplifiers.

EFJ are utter junk. I wouldn't trust my life to one.

Thankfully, the need to do so in CAP is relatively rare.

[denverpilot]

Caveat: The handhelds are just repackaged old Motorola models, and do ok. It's the mobiles that are trash.

[wuzafuzz]

Is the trunk lid metal?  (Gotta ask these days.)  If so, your simplest path is probably a trunk lip mount install with an NMO mount.  With the NMO mount you can easily swap antennas for different uses.  A cheap ham antenna will do well for repeater use.  If you venture into simplex or interop channels you may want a better antenna.

Without going into too much detail, your radio includes interop frequencies outside of the usual CAP channels.  Get with your local communications officer to discuss the frequency range you need to cover.   The antenna itself should be one with broadband characteristics.  Not all 2-meter ham antennas will pass muster for all our channels.

Denverpilot is right, EFJ mobiles have a spotty record at best.  They overheat easily, sometimes drop transmit power to uselessness, and may fail if you look at them sideways or hurt their feelings. 

[Eclipse]

[wuzafuzz]

ROFL.

Doing some DF work overseas?

[♠SARKID♠]

You seek a permanent mounted antenna, methinks.  A black, 1/4 wave whip mounted to the center of the trunk or just above the rear window would probably do nicely and remain in style; looks good on a lot of police cruisers.  As Wuzafuzz said, make sure it's a metal trunk lid.

As for overheating, I don't think you'll have an issue.  If you're concerned, you could try wiring up a small PC fan to blow over the heat syncs of the transmitter or the back of the remote head.

[Eclipse]

My 5100 is mounted in the glove box - never had a heat issue.

[wuzafuzz]

To expand on the heat issue, the radios have a fairly low duty cycle.  If you do much transmitting, like running a busy net, they will overheat quickly.  Running on low power helps but isn't a complete cure.

Most people transmit only occasionally, so low duty cycles aren't an issue.

[krnlpanick]

You seek a permanent mounted antenna, methinks.  A black, 1/4 wave whip mounted to the center of the trunk or just above the rear window would probably do nicely and remain in style; looks good on a lot of police cruisers.  As Wuzafuzz said, make sure it's a metal trunk lid.

As for overheating, I don't think you'll have an issue.  If you're concerned, you could try wiring up a small PC fan to blow over the heat syncs of the transmitter or the back of the remote head.

Yes - metal trunk lid and I had planned on mounting a 12v fan to blow across the back of both the radio and the head unit.

My 5100 is mounted in the glove box - never had a heat issue.

I thought about that for mine, no way, glove box isn't nearly deep enough for it.

The other thing I forgot to mention is that this is a somewhat temporary issue, as I am in the process of rebuilding an old jeep which is where the radio will go when it is complete. So making permanent modifications to the Audi is not my intent.

Good info on the EFJs - I can't justify purchasing a radio this year so as long as it will get me through until next year that is the most important thing. I will ping you guys again on where to go for a new radio when I get that far.

[Eclipse]

I thought about that for mine, no way, glove box isn't nearly deep enough for it.

Sideways with the display facing the driver.  The interior of my glove box unscrewed as one piece, so now the radio
is basically hinged as part of the door itself.

[SarDragon]

Is the trunk lid metal? 

If you intend to use a mag mount, it is essential for that metal trunk lid to be steel. Both my 'Burb and her Prius have aluminum rear hatches.

[Eclipse]

NHQ issued a quantity of N-mount antennas to go with the 5100s - you might check with your wing to see if they have any.

We call them the "baton", because that's what they look like - solid black, about 12" long with a >solid< spring at the bottom.
I mean  >solid<.

I have a 1/4-wave wire antenna on my truck, and I just drive into the garage and it bends over - about once a year(ish) it finally
breaks off and I just remove the stub and put it back in (my bud checks the SWR and I move on).

When wing issued these "batons", I put one on because they had a good rep with good signal, and frankly it looks cool.

Well the first time I pulled out of the garage, this thing just about tore out the garage wall, and bent back the roof of my truck.
(luckily it popped back up).

It's in the case now and only gets used for missions when I have the truck out for a couple days.

[cap235629]

This is what I use

it also is the antenna issued by national with the radios.  You don't need to tune it and it has a 38 Mhz range meaning it will cover any frequency from 138-176 out of the box with no modification.  I use it on all of my VHF applications.

[Eclipse]

Very similiar to mine which is also Maxrad.  This is the spring: 


But it has about a 6-inch "handle" below the spring.

I also had a real nice through-the-glass antenna which would not work on my truck.  Apparently Fords have some
metallic flake or something in their e-glass.  The wing DC bought it from me and it worked great on his Chevy
with the 5100s.

Regardless, if you're looking for "cheap" hit eBay, this stuff is being basically given away there.  Same goes for HT accessories.

[krnlpanick]

I will check with Wing first and see if they have anything they can send over. Beyond that I talked to a couple buddies offline too and one of them suggested a local HAM shop that would be able to fit me with something for about $50-60

Thanks all for the input!

[Eclipse]

For that much you should get about three antennas.

The mag mounts we use with out gel pack radios are about $12 each.

[Robborsari]

How about this one:

http://upload.wikimedia.org/wikipedia/commons/thumb/3/32/Traqueur_acquisition.JPG/220px-Traqueur_acquisition.JPG

[Eclipse]

That thing looks like it belongs on a Star Destroyer!

[SarDragon]

How about this one:

http://upload.wikimedia.org/wikipedia/commons/thumb/3/32/Traqueur_acquisition.JPG/220px-Traqueur_acquisition.JPG

I could drag that on a trailer behind the 'Burb!

[denverpilot]

How about this one:

http://upload.wikimedia.org/wikipedia/commons/thumb/3/32/Traqueur_acquisition.JPG/220px-Traqueur_acquisition.JPG

Want.

[krnlpanick]

Not gonna lie, I wouldn't mind having that sitting in my front yard - especially with a motor on it. I would cheerfully await the first door to door salesman approaching my home...