My new Christmas present...suggestions please.

Right off the bat, I'd like to know how the seller is getting more RF watts out than he's supplying as DC input. He's kinda all over the map with his specs, giving varying input voltages, but even the most generous supplied DC (20 amps at 15 volts) yields a theoretical 300 watts of DC consumed. And RF stages aren't 100% efficient.
But the little thumbnail description of its specs *does* say that it can use, variously, either 2 to 6 watts dead key, or 12 watts (dunno if the 12 watts means peak or dead key; hopefully he means peak, so that the driver radio doesn't over modulate and then have the amp boosting a dirty signal.
But I don't understand how an amplifier that's only being supplied with 300 watts maximum of supply power is going to put out somewhere between 350 and 450 watts.

Maybe they're Santa Claus watts, or the same power that lets reindeer fly.........
73

 

I have the same exact amp. I swing 45 watts into it and I see 400 watts. You'll see the best results at 2.5 watts dead key. Run 8 gauge wire directly to the battery. That peterbilt will run the amp no sweat. You're wondering which radio to use basically depends on what you want. The General Lee or the Galaxy will run it fine. Get a CB Shop with a good rep to set your dead key. You may want to buy your own power meters for the truck where you can keep a eye on your wattage and your SWR readings. ***I would also get your CB Shop you trust to install a fan on that bad boy. Because it'll heat up fast on normal talking.***

 

If I'm not mistaken, I believe the knob on that box allows you to set the box for how much input watts from the radio you wish. I'd say you could probably get away with using whatever 4 watt deadkey/16 watt carrier radio you have.

45 watts swinging to 400 eh? The 2879's are only good for 100 watts peak. Must've been one hell of a happy meter, or maybe it was excess harmonics, since 45 to 400 far exceeds the 1:4 rule.

 

45 watts swinging to 400 eh? The 2879's are only good for 100 watts peak. Must've been one hell of a happy meter, or maybe it was excess harmonics, since 45 to 400 far exceeds the 1:4 rule.[/QUOTE]
A 2 pill with 2 2879 pills will do anywhere from 350-450. It's a proven fact. Ask any CB Shop. Even the amp builder himself knows it'll do that amount of wattage. Just my radio swings 45. I dead key 2.5 and swing 45. I see 400 right on the dot.

 

A CB shop will also tell you that you need an echo board will improve your modulation and blue light leds will make your radio get out better. They'll also tell you that a modulation limiter is useless and that 18 feet of coax are mandatory in getting a good SWR. What they don't tell you is they're con artists in disguise. Especially since they are no longer are required to be certified to work on your radio. The sad thing is those not in the know, namely some OTR truckers, actually "buy" into what they are sold.

A 2SC2879 Toshiba transistor is rated at 100 watts. Times that by two and you're looking at 200 watts. And that's PEP watts, and not RMS which is a more accurate measurement. In case you think I'm full of it, here's the spec sheet from the manufacturer themselves:

View attachment 2879datasheet.pdf

If someone tells you they're getting 400 watts from a 2 pill amp, they're either (a) lying to you, (b) their meter is severely off calibration and/or not set up right, or (c) the extra watts are actually harmonics, which are not even useable anyways.

Thanks for the clarification on the radio. Although over 40 watts of swing is a lot. For best results a 1:4 dk/swing radio is all you want. You'd probably be better at 8 watts of swing if you're only doing 2 watts drive. Not putting down your set up, just stating the obvious.

 

I'm guessing around 40. I'm really not sure. But the best I remember that's what they do. You'll see anywhere from 350-450 out of that linear. I've been into CB's as a hobby now for about 8 years so I know my stuff. Not trying to sound like a "know it all" but it's the truth that that box will do those watts.

 

well all i know is the hotter those 8 tubes get the better mine talks,but what do i know i leave the knowing to ray...lol