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Xforce 200HD

Silanthunter, listen to everyone here except PHYSCO

Everything I posted in this thread is true. You are obviously not knowledgable on competition amps. Maybe you should just stay in the political topic and howl at the moon.
If you don't believe what I posted call Joe Robertson at davemade and he will enlighten you.
 
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Everything I posted in this thread is true. You are obviously not knowledgable on competition amps. Maybe you should just stay in the political topic and howl at the moon.
If you don't believe what I posted call Joe Robertson at davemade and he will enlighten you.
The phrase "competition amp" is a snake oil salesmans term to part a poor unsuspecting individual of his hard earned monies and Joe Robertson is a backwoods knuckle-dragger such as yourself and has many followers such as yourself who fit this description to the T.

I consider myself somewhat knowlegeable about how a push-pull type amplifier is constructed and of the principles on which it operates and I'm sure Joe has as much a clue as I do(who I still think is a clod) to which I'm sure if you asked him he would sell you a bit of that oil also.

I reiterate that physco is a keydown,groupy cheerleader who has no knowlegde of how an amplifier works, does not participate in keydowns :love: and his opinion should be avoided at all cost.
 
Almost every "competition" amp I have seen has had components upgraded (higher voltage rating, etc) in order to be able to run the amp at 16-20 volts. This is not "snake oil",it is only setting the amp up to be driven to the absolute limits and beyond of the output transistors ratings to where when it breaks...and it will, to save the low dollar parts they can't make big money off of. The money is in transistor replacement and the less that has to be done to get the amp back up and running is better for them. Many of those bigger amps don't last over one shootout without having to be rebuilt. But the money they chance to win will most of the time well pay for the repair.
A stock run of the mill amp can't take the abuse that the competition amps do.

BC
 
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Almost every "competition" amp I have seen has had components upgraded (higher voltage rating, etc) in order to be able to run the amp at 16-20 volts. This is not "snake oil",it is only setting the amp up to be driven to the absolute limits and beyond of the output transistors ratings to where when it breaks...and it will, to save the low dollar parts they can't make big money off of. The money is in transistor replacement and the less that has to be done to get the amp back up and running is better for them. Many of those bigger amps don't last over one shootout without having to be rebuilt. But the money they chance to win will most of the time well pay for the repair.
A stock run of the mill amp can't take the abuse that the competition amps do.

BC
Capacitors:
And if you look in anyother amp all the component values are already at 35 to 50 volts on the input values and 500v to 1kv on output components so the snake-oil accusation is valid.
Resistors:
And as far as resistors go I would never use anything other than carbon film, them far-proof (metal oxides) resistors tend to choke rf and should not be used and in the event of an imbalance in circuits such as the combiner sections on output stages the metal oxide resistor would be detrimental to the circuits basic purpose and these resistors are only used as indicators of an imbalance and serve no other useful purpose so in this case more is not more better.

All other components are the same so you're money is wasted on parts that should be perfectly good at lower values.
 
Those amps will take drive up to 120 watts peak and work like that for several years.
Actually the same keying circuit is used up to 8x 2879s. Larger than 8 transistors the only difference in the keying circuit is a larger electrolytic capacitor.
The relays in those amps are shockingly light duty.

On further examination no where in this thread is any mention on this amplifier being a (COMPETITION) amplifier and by your own admission the values used in the key circuit are sub-par for it's operation as constructed and as I recall (COMPETITION) amplifiers do not use a keying circuit and are actually manually engaged (KEYED) to prevent the (COMPETITION) in the event of the competitor (KEYING) early and inadvertently injecting reverse rf into the guys radio next to him thusly relieving him of any chance to compete.

:love:
 
"Those amps will take drive up to 120 watts peak...."

6W typical, 10W maximum for a single 2SC2879.

"Everything I posted in this thread is true. You are obviously not knowledgable on competition amps."

it's bullshit. Joe doesn't have a clue either.

http://www.firecommunications.com/trdbase/2sc2879.pdf
http://www.worldwidedx.com/search.php?searchid=82156
Transmitter Power & Harmonic Line-Section OverSampling

Well I had to give Joe the benefit of doubt not having spoken to him here.:laugh:
 
Davemade came up with some high quality designs, but those that have taken over his designs, often know only how to replicate them, and very little about actuall radio theory and principals.

I will state though, Xforce, Fatboy, and Davemade alike, still build the best amplifiers around, so you can't take that away from them.
 
I agree nightrider. Even though he gets credit the actual Davemade design was not his either. He got it from a Motorola design and adapted it for 11m use.

All I know is the X-Force 200Hd I ran with a Delta Force was kicking butt. With like a 3 watt deadkey and 35 er so peak watts in it was hitting 380 watts and wall to wall audio.
 
I was thinking around 3 watts. Take it on trial and error. I am looking for a 10 meter with variable power.Running a lot through it might get the neighbors upset. I run a dipole and when I get my license I will run late at night. I decided to go ham as there is no CB in my area.
 
I figure 3 watts is the most without tiring the AMP. Push the AMP and it's shelf life goes down dramatically.
 
I won the XForce AMP in a contest on one of my forums. It had no instructions.Anyone know where there is any? Been into radio's for ages and have been told not to drive one too hard. I would say no more then 3 watts.
 

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