Aircraft transmitter power

[frostbite]

On another site I frequent, someone is making ridiculous claims about the output from aircraft radios.

Does anyone know the wattage that is normally fitted to commercial aircraft?

I believe it is in the order of 25w but stand to be corrected.

[BelArgUSA]

VHF transceivers do not require much power to transmit.
I heard anything from 28VDC -10 Watts to 50 Watts...
xxx
For HF it is a different story. Most of my career was using Collins 618-T.
From my pilot ground school notes from long ago - It is -
Input power 28VDC-40Amps - and 115VAC-400Hz - 100 Watts
Output in AM/CW modes = 125 Watts RMS
USB-LSB is 400 Watts PEP. SSB really "boosts" your power.
For transmission range, with HF, the higher power, the better.
xxx
Used to be a "radio-ham" and practiced on long "boring" oceanic flights.
And proper frequency selection is paramount.
Internet changed my hobby. South America to Siberia easier on the web...!
:ok:
Happy contrails

[frostbite]

Thanks for that. Pretty much confirms what I thought.

I believe the chap is talking about VHF AM and he's talking about huge power output (as well as a load of rubbish!).

[west lakes]

As a comparison our company P.M.R. (F.M. Private Mobile Radio ) which is a national system uses 12.5W base transmitters & 25W mobiles (vehicle fit)

[HEATHROW DIRECTOR]

Amazing what those 100W HF transceivers could do.. A pilot friend of mine was a radio ham, like me, and I've worked him in his "office" around the world.

[BelArgUSA]

LHR Director -
xxx
Well, when I used to do "CQ CQ Air Mobile" you should have worked me.
My QSL card was a picture of a 747-200 with my LU- call sign.
Made DXes from OZ/South Pacific to Europe on 20/40 meters voice R/T.
And from my city apartment using a window screen as antenna...!
The good old days -
xxx
Greetings to you -
:}
Happy contrails

[HEATHROW DIRECTOR]

BelArgUSA.. Great days indeed. I was driving to work at Heathrow one morning in the late 70s and a DC10 flew over on the ILS to 09L. At that moment a very loud American voice came up on 2m. I said "QRZ?" and he came back with a US/AM call. When we established contact I asked where he was...... it turned out he was flying that DC10!

Take OM.. 73 de G4DYO

[Ten West]

My handheld "Standard Horizon" marine transceiver for boating is only 5 Watts RMS and that has a useful range. Fixed boat ones are 25Watts and perfectly fine for all the places you're likely to want to sail for a day.

You really don't need masses of power for VHF transmissions. The biggest limiting factor for boats is the "Line of sight" nature of FM rather than lack of power. Not such an issue in an aircraft.

[411A]

I believe it is in the order of 25w but stand to be corrected.

Collins 618M3 VHF comm, 25 watts.
King Gold Crown KTR9000 VHF comm, 25 watts.
King Gold Crown KTR900/905 VHF comm, 20 watts.

I have two of the latter in my my private airplane, 40 years old, and they still work to perfection.

The King Gold Crown line was first introduced in 1968, and is of comparable quality to the Collins units of the period.