Higher voltage = higher wattage output?

[hammer0630]

OK I just received a 47 amp 51 surge power supply because I always felt my Mega Watt S-400-12 power supply might be over taxed and not allowing my amp "RM ITALY KL-503" to work to it's fullest, but the Mega-Watt supply always ran cool and has never shut down. Well after checking the meter with the new power supply DK. and audio peaks I now know by comparison that the old Mega Watt is not only powerful enough but has absolute silence when in operation. The new one gave me 9 db's of hash like others I have tried. Now when I brought out the multi meter to check my voltage I noticed on my watt meter the wattage out put for example 12 watts flat vs.13.75 can mean a whopping 100 watt difference 13.75 is the higher reading of course. Now I know a little about automobile's and if you got a 12 volt reading you would soon have a dead battery and speaking on dead batteries say you have a good battery and alternator and left the lights on after getting a jump start and checking your voltage it would be common to get readings as in the high 14's. I also run a separate power supply for my 148, meter lights,etc. It appears to be a Trip Lite very large unit big heat sinks heavy but I do not know the output "no I.D. anywhere" but is also silent in operation. Now back to the question if I had this amp in my mobile which puts out more than 12 volts most of us would not worry so is the mobile base running higher volts and getting dramatically more watts is this somehow a false reading and would the amp soon go kaput I am running the same amps in both my trucks for nearly two years they run cool and still work. I really want the nearly 100 watt increase by running the power supply voltage at 13.75 but get the feeling I am going to get the air taken out of my balloon Hey thanks for reading guys!

 

[wavrider]

Google is your friend.

Power output formula.

P=E/I*efficiency

 

[hammer0630]

Google is your friend.

Power output formula.

P=E/I*efficiency

Huh?

 

[Captain Kilowatt]

Huh?

Well that answers some questions. :laugh:

 

[AudioShockwav]

I really want the nearly 100 watt increase by running the power supply voltage at 13.75

When the Motor/Alts are running, your truck is most likely running between 13/14 volts.
Resting voltage is a bit lower, but to get to the point, you are the only one that will ever know that 100 watt difference.
The guy on the other end of the conversation will be very very hard pressed to see the difference between, say 400 or 500 watts in an everyday QSO.
Short story...it is really not worth worrying about unless what ever you are going to do is going to double your power output.



73
Jeff

 

[hookedon6]

Well that answers some questions. :laugh:

yeah, I stopped reading about 1/2 way thru the post.

punctuation is a friend too

 

[bob85]

google that equation again

Google is your friend.

Power output formula.

P=E/I*efficiency

 

[hammer0630]

Nice! I guess asking a question about one hundred watts is ridiculous on this forum. I wonder how many people out there do not post any questions because of this ridicule they will receive. And no this is not a isolated incident. It's one thing to answer a smart ass question with a smart ass answer but this attitude of "you are not worthy peasant" is prevalent here or it's the same bunch talking all the time.

 

[Robb]

Nice! I guess asking a question about one hundred watts is ridiculous on this forum. I wonder how many people out there do not post any questions because of this ridicule they will receive. And no this is not a isolated incident. It's one thing to answer a smart ass question with a smart ass answer but this attitude of "you are not worthy peasant" is prevalent here or it's the same bunch talking all the time.

Don't worry about ridicule for asking a legitimate question. The Moderators will deal with those that ridicule. The only way to get an answer is to ask a question. You aren't born with this info tatooed to your butt; so ask away. Don't pay any mind to the mindless who can't figure that out.

As far as seeing more watts out with more voltage - provided there is ample amperage available too - sure it will.
The real question is not if there are going to be more watts; but what are the quality of those watts?
Or - am I pushing that amp closer to failure just for some more watts that no one can tell the difference with anyway?

 

[hammer0630]

Don't worry about ridicule for asking a legitimate question. The Moderators will deal with those that ridicule. The only way to get an answer is to ask a question. You aren't born with this info tatooed to your butt; so ask away. Don't pay any mind to the mindless who can't figure that out.

As far as seeing more watts out with more voltage - provided there is ample amperage available too - sure it will.
The real question is not if there are going to be more watts; but what are the quality of those watts?
Or - am I pushing that amp closer to failure just for some more watts that no one can tell the difference with anyway?

Thank you, I know about the number of watts it takes to make another S unit now that I wish I didn't know it separates the men from the boy's. I am not sure what you mean by "the quality of the watts" and I have the amperage needed also. I think what makes me wonder about this voltage thing is I have never heard a word about this when wattage is or was such a big thing that something as simple as this can bring you so many more watts.

 

[Robb]

Thank you, I know about the number of watts it takes to make another S unit now that I wish I didn't know it separates the men from the boy's. I am not sure what you mean by "the quality of the watts" and I have the amperage needed also. I think what makes me wonder about this voltage thing is I have never heard a word about this when wattage is or was such a big thing that something as simple as this can bring you so many more watts.

Radios and amps can generate artifacts/harmonics. Pushing up the voltage in an amp is just going to create more by aggrevating this condition. Makes a radio sound like crap. These get dumped on the bands and might even create a legal issue (getting busted by the FCC is easier when your station does this). Try running the amp at 13v instead of trying to push it towards 18v. Less power out; but runs cooler and less harmonics.

 

[W5LZ]

Increasing the input voltage may increase the output power but not as much as you might think. That's where that efficiency part of the equation comes in. It will also depend on if that amplifier has a voltage limiting circuit. The average efficiency of most solid state amplifiers is around 50%. So, don't expect much increase in output power.
- 'Doc


(All RF is AC, not DC, so typical automotive electronics won't apply.)

 

[Robb]

IIRC, hammer0630 uses an RM Italy KL-503 amp. There are some guys on the internet that run as much as 20v into this amp and getting nearly a kilowatt of power out of it. But that is kinda misleading. Even if it can be run up that high in voltage - and it survives - just how many of those watts are actually on the target freq being used? Probably no more than that amp is rated at - maybe 3 or 400 watts. The rest end up as spurious harmonics.

Sure, a meter may show a kilowatt of power output. But power meters are dumb (even the best of them); they just register power output. But does not tell you that they are going everywhere besides the target freq. Put a low pass filter on the output of the amp and then put it into a meter. The results will be different. Bet it shows far less output then. Some of those harmonics are still on that band that the filter isn't catching (eg: adjacent channel 'bleedover'); so it will still register some of it for that total output figure. But not honest, on-target watts . . .

 

[hammer0630]

That is some good info guys, and running 20 volts to me sounds crazy my supply can not go over 15 volts and I am running 13.75 volts which brought me up quite a ways from where I was at, and should be some what accurate. My extra watts is not a toy to me it is needed for two way communications cell service is very bad also and I live in the mountains. I don't talk skip and there is not another base station in my whole county. And I am far away enough from the Highway channel 19 is always blank here.

 

[psycho]

IIRC, hammer0630 uses an RM Italy KL-503 amp. There are some guys on the internet that run as much as 20v into this amp and getting nearly a kilowatt of power out of it. But that is kinda misleading. Even if it can be run up that high in voltage - and it survives - just how many of those watts are actually on the target freq being used? Probably no more than that amp is rated at - maybe 3 or 400 watts. The rest end up as spurious harmonics.

Sure, a meter may show a kilowatt of power output. But power meters are dumb (even the best of them); they just register power output. But does not tell you that they are going everywhere besides the target freq. Put a low pass filter on the output of the amp and then put it into a meter. The results will be different. Bet it shows far less output then. Some of those harmonics are still on that band that the filter isn't catching (eg: adjacent channel 'bleedover'); so it will still register some of it for that total output figure. But not honest, on-target watts . . .

Who has been running 20 volts into KL-503? Run them over 15 volts or overdrive them and they pop like a bubble.