CALCULATE AVERAGE POWER TO PEAK POWER

[TonyV225]

Does anyone know the formula for this?? I had it somewhere and was just thinking about it and wanted to show my kids this as there getting ready to study for there General tickets. It was kind of a cool and simple meathod and Im having a brain lock and cannot remember how it worked.

It had to do with if your looking at an average meter thats accurate you could ad on a percentage that brought you close to your peak power. If someone here knows or remembers it please help LOL!! Ill keep looking through books and notes here. Thanks in advance....Tony

 

[Qwazyone]

Average power x 1.707 sticks in my head for some reason, but some brain cells were lost studying for extra

Proof brain cells were lost, in the Arrl general class manual page 4-6 Vpeak= 1.414 x Vrms

 

[W5LZ]

Avg power times 1.414 is Peak power. Peak times .707 is Avg. Peak time 2 is Pep.

 

[Beetle]

Avg power times 1.414 is Peak power. Peak times .707 is Avg. Peak time 2 is Pep.

Peak x 2 is peak-to-peak, not PEP.

 

[TonyV225]

THATS IT!!! AVG x 1.414 =?? I had to laugh because actually 414 is one of the area codes for Milwaukee Wi which is how I used to remember this duh!!! Thanks again for the help!!

 

[W5LZ]

... we're talking Bird watts, ain't we??

 

[Shockwave]

Formulas and calculations are not my strongest areas. However, something is telling me peak power is more then 1.414 times average. We agree that peak voltage is 1.414 times RMS but what is happening to the current has been overlooked. Power is volts times amps. If you raise the peak voltage 1.414 times, you have also raised the peak current into the 50 ohm load by the same amount. The end result is a larger figure.

 

[jazzsinger]

Avg power times 1.414 is Peak power. Peak times .707 is Avg. Peak time 2 is Pep.

you can't use the same forumla for converting current or voltage rms to peak and vice versa on power.

for 100% modulation Peak Avg power is 1.5 times Avg/Peak carrier power and pep power is 2.66 times Peak Avg power or 4 times Avg/Peak carrier power.

Avg carrier power is the same as Peak carrier power because there is no modulation to swing it forward.

for a 4 watt carrier modulated at 100% positive modulation you should see 6 watts Peak Avg forward swing on an Average meter and 16w PEP forward swing on a PEP meter.

as beetle correctly says 2 x Peak is P-P not Pep.

Confused,you will be.:headbang

 

[jazzsinger]

... we're talking Bird watts, ain't we??

Are Bird watts special watts? Because if they are you'd be better talking zetagi or dozy watts or even better AM Power watts,now they give real impressive power figures,a bit like antron/solarcon and at one time sirio gain figures.


AM Power watts combined with antron/solarcon gain are my particular favourite,then anyone can run kw+ from a barefoot export radio.If your really power mad you can throw in some pama coax cable loss figures and your barefoot radio is verging on broadcast standards.

The other benefit i love about using AM Power watts is they come with copyrighted hydroponic cooling system so you never need a fan,lol.

 

[Captain Kilowatt]

I'm not sure there is any formula that can be applied and be accurate unless a pure sine wave is being used to modulate the carrier.The power will have to be measured and not calculated. Everyone's voice is different and has a different average to peak ratio which will be reflected in the average/peak ratio of the power output from the radio. Let's throw in some processing just to screw things up a little while we are at it.

 

[jazzsinger]

I'm not sure there is any formula that can be applied and be accurate unless a pure sine wave is being used to modulate the carrier.The power will have to be measured and not calculated. Everyone's voice is different and has a different average to peak ratio which will be reflected in the average/peak ratio of the power output from the radio. Let's throw in some processing just to screw things up a little while we are at it.

Yep i should have stated in my previous post modulated to 100% with a pure sine wave but i assumed everyone knew that was the case, Bad jazzsinger.

a human voice will have a peak to avg ratio of between approximately 2:1 and 1.53:1 depending on the voice,which equates to about 50% to 65% duty cycle.Which is why if i'm not mistaken 2 tones instead of one are used in ssb pep measurements to roughly approximate the human voice and is the reason when a radio is setup that way will show slightly different pep levels depending on who's speaking into it.if a single tone were used it would show 100% duty cycle which is far higher than the human voice would drive it.

of course i could be wrong,wouldn't be the first time :headbang:headbang

 

[TonyV225]

Captain you guys are killing me and Jazz abot snt me into a full cardiac arrest with the laughing I did at his last reply!!! I understand theres no true way of calculating down to the last watt but I know that a person can get closer to the ballpark figure....Well closer than what some meters show thats forsure and that is what I was after.

I will explainm to the kids that this is only a ballpark figure aswell and is not a guarantee spot on way to do this bu6t as I said it a better figure than what some meters show. I actually checked this 1.414 against a True Perak reading meter here and it is surprisingly close to what Im seeing give or take.

Jazz apparently I need the Am Power guide to RF transistor secrets so I can really impress my kids with all this magic that one can peform to get that extra gain this proffessor has figured out.

 

[jazzsinger]

Jazz apparently I need the Am Power guide to RF transistor secrets so I can really impress my kids with all this magic that one can peform to get that extra gain this proffessor has figured out.

Yep,your quick to catch on to the mythbusting secrets of AM Power supremacy Tony.Makes the screwdriver experts guide to systematically destroying cb's look like an extract from Grimms fairytales.

 

[TonyV225]

LMA:laugh:RTF!!!!!!!

 

[W5LZ]

Define peak envelope power.