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Amp?

Nick23

Desperado, 785
Aug 16, 2013
389
31
38
Bangor, ME
I just got a Cobra 29LX Camo with variable power. I want to hook it up to an amp, but I'm lost as to what to get. Its not for skip. I need the power to talk to my friend outside of town. I wanted around 800 watts. What amps would I have to get for that kind of output? I have all my ducks in a row, as far as coax and:bdh: alternator requirements. :bdh: :bdh: :ohmy:

Many thanks guys
Nick
 

You should not need 800W to talk that far.
I would suggest a Texas Star DX500. Drive it so you dead key about 100W and swing about 450 and it'll last a long time and sound good on the air. The difference in signal on the receiving end from 500 to 800W isn't much at all. The best way to increase your signal strength on the receiving end is antenna. Big gains can be found there, usually the most bang for the buck. What antenna are you running?
 
The new TNT or and X~Force amp with that is at least biased b. the new TNT amps are very well made IMO, or a Davemade. The TNT 800 would work well with that radio IMO. God bless.
 
So a 1x4 for this tuned Cobra. I was wanting to do an rfx75 to it but decided against it. I run a Predator 10-K 12 inch shaft.
 
Why is the TNT 800 rated at 800 watts and an Xforce standard 1x4 rated for 1100? Also, I'm guessing I should get the low drive amp? What would be the difference between a 1x4 and a 2x4 for this setup?
 
I just got a Cobra 29LX Camo with variable power. I want to hook it up to an amp, but I'm lost as to what to get. Its not for skip. I need the power to talk to my friend outside of town. I wanted around 800 watts. What amps would I have to get for that kind of output? I have all my ducks in a row, as far as coax and:bdh: alternator requirements. :bdh: :bdh: :ohmy:

Many thanks guys
Nick

Sort your antenna out. I can do 30 miles with 4W on flat ground mobile to mobile. More power won't get you over the radio horizon or over hills so if he's over 60 miles or so away or there's a hill between you and him you could have 800,000W and you'd not make it. I have a situation here where from my home there's a hill between me and a friend 12 miles away. 400W didn't make it but I can drive a mile down the road so the hill is no longer in the way and have no problem hitting him with 4W.

800W is going to require about 160A. Have you thought about how you're going to power that? You think you have your ducks in a row regarding coax etc but what coax are you planning to use and how are you planning to mount the antenna?

What do you think 800W is going to do for you other than get you a prize in a whose got the biggest dick in a willy waving contest amongst other equally stupid people who think you need hundreds of watts to talk to a guy down the road?

800W is half a S point more than 400W and only 1.5 S points more than 100W. Either of those are far easier to deal with installation wise than 800W.

You say you've got an alternator sorted. You do realise that you're going to have to sit there talking to your buddy with your foot on the accelerator revving the crap out of the engine because alternators put out next to nothing at idle? That is assuming of course that the engine doesn't cut out when you key up from all the RFI you're going to have getting into the electronics. If you insist on going down this path you're going to need a bucket full of 31 mix ferrites because you're going to have to put them all over the wiring harnesses wherever there's an ECU or such.
 
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So are you saying a straight 4??? Wouldn't this radio severely under drive it?

Under drive? No, not hardly. 2879 transistors have the reputation of making 250w per, but when you over volt/over drive them to do that is when the dash lights start going crazy and the engine stumbles and dies.
 
800 watts out at 50% eff = 1600 watts consumed at 13.8 volts which requires 116 amps just to run the amp. Extra is of course required for the driver and regular vehicle operations. Total current requirement is likely to be is excess of 160 amps.
 
And a class c amp is closer to 65-70% efficient. I ran 800w out of a 1x4 with a 135a alternator for a couple years when I got started. It didn't even dim the headlights.
 

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