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How much can i drive a dave made amp

Yes you can drive your big radio into a 2 pill and , like I said before, IF you are careful with everything it will live.
But it is risky and it dies on you, no one to blame.
PC, I think you are well versed in how things work and would not expect an experienced operator run that setup into a 2 foot fiberglass no ground plane antenna with some crappy coax and cheap connectors.
But for a casual user that does not have a good working knowledge of RF this might be a recipe for a melt down.
In this case we are talking about a Big Radio driving 2 x 2290 driving 4x2879's
The 4 at the end are sitting in a electric chair.
If anything goes wrong you can kiss the 4 Toshiba's good by, along with what ever else going up.
They are expensive, ya you can still get them but you are going to whip out the platuium card.
I get a bad feeling when I smell 10 Ohm smoke.
It is much better to over build/buy and drive it easy than run things on the edge were a small mistake will ruin things.
Even the 2x6 is better because at least you have a couple more devices to spread out that drive.
( if it is splattering the whole band part of it might be the radio that is driving it has an issue)
Again, this is my opinion after playing radio for lots of years.
A lot of people bag on Hams that run a 2Kw Amp but if you are only running it at 50% output and something squirrelly happens a little further down the coax, it stands a better chance of surviving.
And at that output it runs cooler and should live longer.
Now.
If you have a reason to try to extract every last watt out of each transistor then yes, you can drive the Snot out of them and volt them to insane levels.
It will shock you how much you can force a transistor to output.....for a little while.
How long depends on how well you prepare before you stress the device in use.
And keep a spare bucket of replacements handy.
If you want them to last a long time, over build , give yourself lots of headroom and don't run things on the edge.
2 cents.

73
Jeff
 
Good point. I hadn’t really looked at like you said, the experienced vs. the inexperienced. Everything else is all good points as well, exactly why I said it’s not the greatest idea but possible.

There are some that want every last watt, the meter worshippers I guess is a good term. I agree 100% that it’s better to ease it along than wring it out.
 
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Yes you can drive your big radio into a 2 pill and , like I said before, IF you are careful with everything it will live.
But it is risky and it dies on you, no one to blame.
PC, I think you are well versed in how things work and would not expect an experienced operator run that setup into a 2 foot fiberglass no ground plane antenna with some crappy coax and cheap connectors.
But for a casual user that does not have a good working knowledge of RF this might be a recipe for a melt down.
In this case we are talking about a Big Radio driving 2 x 2290 driving 4x2879's
The 4 at the end are sitting in a electric chair.
If anything goes wrong you can kiss the 4 Toshiba's good by, along with what ever else going up.
They are expensive, ya you can still get them but you are going to whip out the platuium card.
I get a bad feeling when I smell 10 Ohm smoke.
It is much better to over build/buy and drive it easy than run things on the edge were a small mistake will ruin things.
Even the 2x6 is better because at least you have a couple more devices to spread out that drive.
( if it is splattering the whole band part of it might be the radio that is driving it has an issue)
Again, this is my opinion after playing radio for lots of years.
A lot of people bag on Hams that run a 2Kw Amp but if you are only running it at 50% output and something squirrelly happens a little further down the coax, it stands a better chance of surviving.
And at that output it runs cooler and should live longer.
Now.
If you have a reason to try to extract every last watt out of each transistor then yes, you can drive the Snot out of them and volt them to insane levels.
It will shock you how much you can force a transistor to output.....for a little while.
How long depends on how well you prepare before you stress the device in use.
And keep a spare bucket of replacements handy.
If you want them to last a long time, over build , give yourself lots of headroom and don't run things on the edge.
2 cents.

73
Jeff
Thanks Jeff ill be using it in base with a SPT500 from 1975, and its for good Dx in short period not to be chattering long periods, ive been thinking of the step attenuator and a representative at stryker told me it safe for the radio and will not over drive the Dave made Base amp the radio is set to 2 watts dead key modulates 40 watts peep and the amp is putting 800 watts dead key and 1200 peep modulated
 
I remember a 'worldwide' CB operator from around 1979 who loved his Yaesu FT101.

And his Pride DX300.

His buddies kept telling him he could use them together. Just turn the carrier down.

Yes, the carrier would turn down below 4 Watts on the FT101.

But turning down the mike gain to keep the peaks below 20 Watts? Sure, so long as you keep it turned down that low.

Naturally, he blew up the Pride. I showed him how to turn down the Yaesu, and then predicted that sooner or later he would sneeze with the mike keyed, and "POOF!".

Sure enough, he would get told his "britches got dusted" and would start cranking knobs.

Shortly after, would come the "POOF!".

The third time he blew up the Pride, it damaged the Yaesu as well. By that time he decided that maybe I was right telling him not to use that radio with that amplifier.

Third try ( or third "POOF!") was the charm.

73
 
Thanks Jeff ill be using it in base with a SPT500 from 1975, and its for good Dx in short period not to be chattering long periods, ive been thinking of the step attenuator and a representative at stryker told me it safe for the radio and will not over drive the Dave made Base amp the radio is set to 2 watts dead key modulates 40 watts peep and the amp is putting 800 watts dead key and 1200 peep modulated

I just can't see the amplifier lasting very long at all.
I drove a 2 x 2879 Toshiba's with a Stryker 955. Second key up, and the transistors were roasted.
I will be surprised if the 2 x 2290's don't go before the 4 x 2879's ......
 
If you turn the carrier down and adjust the mic gain to keep the pep power where is needs to be you can get away with it. Make a mistake and it will cost you. If anything goes into oscillation at such low power levels all bets are off. I used to run my S9 with a 4 pill xforce and it was a sweet set up.

If you want to post a good pic of the inside I will show you how to bypass the 2 pill section when I have time to set in front of a PC. It may be the weekend but I'll get around to it. It consists of removing a resistor, moving a piece of coax and disconnecting the b+ wire from the 2 pill.
 
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