I want the straight Scoop!

[dieselburner]

I have just purchased a 2x8 XForce X800 amp used. It has 2 2sc2290's driving 8 2sc2879's. I have a Bird meter that is set up for average power and peak power. When I set the driver to 3 watts dead key and have the bird set to average, I get 250 watts. When I modulate the signal it swings up to about 400 watts. When I set the Bird to read peak watts, I have 250 watts dead key and 1200 watts when I modulate. I measured voltage at the amp's input at 14.2V with the engine running with no key down and 13.6V with it keyed and modulated. Are these numbers in the ballpark for this amp? I thought it would do more than this but I do not have any experience with this amp. Any info would be appreciated. Thanks

 

[n0zna]

about right...dead key a little low...

 

[9C1Driver]

I would think it could/should do 1600-1800 peak. How big is your alternator?

 

[dieselburner]

157amp with twin batteries. Its in a diesel p/u. I am only getting a half volt drop on transmit so I don't think I have a charging problem...But maybe I guess.

 

[dieselburner]

Anyone have any experience with what these amps do?

 

[9C1Driver]

157amp with twin batteries. Its in a diesel p/u. I am only getting a half volt drop on transmit so I don't think I have a charging problem...But maybe I guess.

10-4 only reason I asked was this is off the X-Force site.




X800

Transistors 2 SC2290 driving 8 2SC2879
Dimensions H 5 1/2" x L 14 1/4" x W 13 1/2"
Amp Draw (continuous) 80
Amp Draw (maximum) 180
Class C
SSB Delay available
Pre-amp available
No Driver Required
Power Output (RMS) 850 Watts
Power Output (PEP) 1800 Watts

 

[wavrider]

http://www.datasheetcatalog.org/datasheet/toshiba/1468.pdf

There is the link to the specifications of the 2SC2879 transistors.

That is the straight scoop on what the components in the final section of that splatter box will do.

Hype in advertising is what you read on the manufactures site.

 

[Justme]

Most H.F. amplifier sections in amateur transceivers will use 2 of them to get 100 watts output.
There is a reason for that, IMD is the lowest at 50-60 watts output and going up steeply from there.
So, stressing these transistors to 150 -200% of their rated output is shortening their lifecycle and causing massive dirty output, certainly in Class C ...
You measure not only output power on your frequency but also the harmonic distortion.

There is no easy way to make that kind of power on the cheap and cheerfull way without causing lots of interference.
I would like to see the plot from a spectrum analyser on that amp running full power and have my eyes watering...

 

[w9cll]

You are getting 1200 watts pep out, do you really need more?

 

[psycho]

The alternator is insufficient. You need no less than 250 amps for the amp and truck itself.
The 1600 watts peak rating is at 15 volts.

 

[psycho]

You are getting 1200 watts pep out, do you really need more?

Would you be happy if you purchased a new Mustang 5.0 expecting the advertised 410+ horsepower only to find out it's only delivering 300 hp? It's not about what you need, but what you paid for.

 

[IRock817]

All radios and amps I've ever seen use what I'm calling false advertisement! If they used avg power numbers, we wouldn't be so likely to spend our hard earned cash.

 

[TonyV225]

You always Have to remember to take into consideration how these companies or builders do their testing. If its lab equipment or what they use in general. Also you have to look at where the amplifier is actually going to run efficiant and clean. For example I rememebr playing with the Texas Star 1600 I had sure it would do 1600 if ya layed the boots to it or even more if you pounded p!$$ out of it.


If I remember correctly that amplifier on the 11 meter band was rated at 1200 watts with its 8 X 2SC2879 transistors. 1200 watts!! Good lord THATS PLENTY!! And way more Than whats ever needed Ive never even had to run legal limit on the HF bands The biggest bang for your buck and greatest improvment thats going to be noticable is YOUR FIRST 500 WATTS Ive noticed and heard a huge difference in the first 250 watts aswell.

 

[w9cll]

Would you be happy if you purchased a new Mustang 5.0 expecting the advertised 410+ horsepower only to find out it's only delivering 300 hp? It's not about what you need, but what you paid for.

No but that s totally different animal.

 

[w9cll]

You always Have to remember to take into consideration how these companies or builders do their testing. If its lab equipment or what they use in general. Also you have to look at where the amplifier is actually going to run efficiant and clean. For example I rememebr playing with the Texas Star 1600 I had sure it would do 1600 if ya layed the boots to it or even more if you pounded p!$$ out of it.


If I remember correctly that amplifier on the 11 meter band was rated at 1200 watts with its 8 X 2SC2879 transistors. 1200 watts!! Good lord THATS PLENTY!! And way more Than whats ever needed Ive never even had to run legal limit on the HF bands The biggest bang for your buck and greatest improvment thats going to be noticable is YOUR FIRST 500 WATTS Ive noticed and heard a huge difference in the first 250 watts aswell.

And it's all going to depend on what your feeding it into. Feeding 1200 watts in at a 5-10% efficient antenna is a waste of wattage. Feeding 500 watts into a 70% efficient antenna is much better.

Sorry drifting off topic. OP hope you get everything you want out of that amp.