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R6+ / Cr, Sheeps Maybe
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Discussion Starter #1
Question for to the rally hams out there. If you have your radios permanently/ semi-permanently mounted in your vehicles, how do you have them installed? I'm debating a dash mount (nice flat tray already there) or some macgyvered set up with the cupholders. Having it on the center console or passenger seat is a pain when bouncing along stage roads. I have an F150 if that clarifies what I'm working with

Just looking for suggestions before I go out buying parts and pieces
 

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RallyX Weenie
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Here's my not-even-semi-permanent mount for my 2900 in my 4Runner:



Flat aluminum bent by hand. Ends plastidipped to make sure it sticks, as well as protect the glove box. Upper "hook" ends are trimmed w/ dremel to fit the latches - after this picture, I've bent them further so they're "captive" parts and don't come off the latches.
Latches from McMaster-Carr (6082A25) are pop-riveted on.
2900 bracket w/ mounting holes countersunk, then bolted to the aluminum.

Did just fine as 00 at Idaho in 2012, and plenty of just driving around.
 

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your other left, you idiot
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R6+ / Cr, Sheeps Maybe
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Discussion Starter #6
I have the 2900 already so the detachable faceplate option is out. Is there anything wrong with mounting it on the top of the dash? I've seen commercial radios mounted there a lot or is it not reccomended?
 

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I have the 2900 already so the detachable faceplate option is out. Is there anything wrong with mounting it on the top of the dash? I've seen commercial radios mounted there a lot or is it not reccomended?

Dash mounting has some issues if not done carefully and robustly, as in becoming an unguided, heavy missile in the event of an accident. Secondarily, there may be some concerns around theft due to the highly visible nature of the dash --- AND possible issues with overheating if it is being used while in full sun.

Here are some other options that I find helpful when working rallies. This is specific to Subarus, but most of the ideas could be generalized to other vehicles:
http://forums.nasioc.com/forums/showpost.php?p=31230062&postcount=442 and http://forums.nasioc.com/forums/showpost.php?p=31552612&postcount=472

Best wishes!
 

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Here's my not-even-semi-permanent mount for my 2900 in my 4Runner:



Flat aluminum bent by hand. Ends plastidipped to make sure it sticks, as well as protect the glove box. Upper "hook" ends are trimmed w/ dremel to fit the latches - after this picture, I've bent them further so they're "captive" parts and don't come off the latches.
Latches from McMaster-Carr (6082A25) are pop-riveted on.
2900 bracket w/ mounting holes countersunk, then bolted to the aluminum.

Did just fine as 00 at Idaho in 2012, and plenty of just driving around.
NICE idea and fabrication!
 

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I've done top-of-dash mounts before, including on my current car. I like that it places the radio where I don't have to look away from the road to see it, and where it won't break my (or my passenger's) knees in an accident. Cons are that it does visible damage to the dash (if you remove the radio later to sell the car, say) and running the wiring can be a little more challenging. It's certainly much better than having the radio loose on the seat, as far as crash safety goes.

I haven't had any issue with overheating with my radios, but I agree the possibility is there.

I no longer see theft as a big issue. Thieves generally aren't going to know what an amateur radio transceiver is; they'll be looking for expensive stereos, smart phones, or GPS units that can be easily grabbed.

The important thing is to make sure you've anchored the radio to a solid, metal part of the dash. This isn't *usually* too big a problem because most dashes are largely metal under the padding, for crash safety reasons. I prefer to use through-bolts and lock washers, the biggest size that will fit through the radio's mounting bracket. If access is restricted large self-tapping screws will work, but make sure they get a good 'bite' into the metal. If it starts to loosen, not only is it a crash hazard, but the rattling will drive you insane. (Stage roads can loosen up almost anything. Blue Loctite is not overkill.)

Investigate what's under the spot you're drilling into before you start drilling...hitting a dash wiring harness with the drill really sucks. ;) On cars with passenger side airbags you have to be careful the radio doesn't end up in the deployment area. On cars without airbags, try to put the radio where the passenger won't hit their head on it in an accident. My Mercedes had a great spot on the dash tray right next to the instrument binnacle.

For wiring, I ran the coax along the windshield seal up into the headliner; the power wiring runs through the trough between the dash and the windshield over to the side of the dash, where there was an existing hole next to the A pillar. Another simple and inconspicuous method on some cars is to drill a small hole through the defroster duct, under the dash, and run the wires up through it.
 

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Wherever you mount it, make sure the main body of the unit has free air flow. Overheating results in the same thing in all of these mobile units: The unit reduces transmit output power to protect itself. (They all have temp sensors inside of them.) It will cut back from 50W to 25W to 10 and even down to 5W if it has to. Mounting one under a seat in a tight spot, or in anotherwise convenient looking 'pocket' in a dash or center console will be a problem in this way. The glove box mount pictured is very good for airflow.
 

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Wherever you mount it, make sure the main body of the unit has free air flow. Overheating results in the same thing in all of these mobile units: The unit reduces transmit output power to protect itself. (They all have temp sensors inside of them.) It will cut back from 50W to 25W to 10 and even down to 5W if it has to. Mounting one under a seat in a tight spot, or in anotherwise convenient looking 'pocket' in a dash or center console will be a problem in this way. The glove box mount pictured is very good for airflow.
Mark is spot on with regard to his main assertion of ensuring good airflow to curtail onset of the overheating protection regime he described -- and he is an engineer, with far better credentials than mine. Those issues were on my mind when I mounted my radio under my WRX seat -- right next to a heat vent. Additionally, I was worried about the accumulation of dust which might cause heat build-up and fan failure -- and that passengers might damage the radio or cabling with their feet. Thankfully, after a number of years of use I can report that none of my worst-case scenarios have cropped up. I did check the radio more often when first installed, but now I just make sure to give the radio a good vacuuming a couple of times a year. My air-conditioning is not up to snuff, so I do have the windows down a fair bit and the fan on alot, but still no big dust issues. I have worked Sno-Drift a number of years and had the heat running a fair bit, with no issues. I have even run my SWR/wattmeter in-line for a number of rallies and never saw thermal protection implemented. Most radios will display some type of error message, so you shouldn't typically have to do what I did.
 

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Some things are learned by experience or experiment more than college degrees Dave...LOL...so I won't gainsay your experience one bit. And before folks get too panicky about my comments, I'll qualify it all by saying that this type of overheating in a ham mobile typically will only occur in heavy duty cycle usage, and can happen even if the unit has good airflow. Most rally control location radios will not see that type of high duty cycle use, and marshall locations will usually see even lower duty cycles. So for rally use only, it may not be too big a factor; just be aware.

A long rag-chew on the mobile while cruising around will put a higher duty cycle use than most rally use; the one time that a mobile in rally use will see a high duty cycle is if it is a temp net control or a mountain top relay. If you use it for 30 minutes or more almost constantly then you will need a fan on it regardless. But good cooling contributes to long life in electronics, so as a practice, keeping good airflow on a radio is a good idea.
 

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Linking with Mark's theme about long cycle use, I have a couple of 4 inch 12 volt computer system fans (scavenged from dead power supplies) that I can zip-tie to my radio in a pinch, should the duty cycle issues he has described rear their ugly head. Pretty cheap and easy accommodation... I have seen and/or worked the temporary net-control and mountain top relay scenarios Mark described, they are more common in rally communications than we would all like to admit, unfortunately.

I should have offered the caveat that my scenario of under the seat clean & cool operation (and no damage from feet/"cargo"), could well be a statistical aberration, and Mark's guidelines are definitely the more preferred protocol.
 
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