Re: What happens if you exceed the wattage of a transmitter antenna

Just thought of one more issue. Some antennas have capacitors in them and they will have a limit of voltage and current .

Some antennas can heat up enough (usually the coils) to melt out the plastic parts seperating the elements.

Anyway it is usually the components that make up the antenna that determin how much power they will withstand.

Too much power and you either get a voltage breakdown of the components or a heat melt down of the components, or a combination of both.

Ralph Mowery wrote: ================== >

.... Phil

Sometimes they do, some times they don't.

Around 1980 some hams were sending radio teletype using around 500 watts into trap beams and melting out the traps. The antennas were rated for the full power limit of over 1000 watts. However as it turned out the

Ralph Mowery wrote: =================

** Once upon a time loudspeaker makers rated their products power handling based on normal home usage - even if used with a guitar amplifier. Then " hard rock " was invented and blew that method out of the water.

..... Phil

Talking about speakers I just love the way some computer speaker/amplifiers were rated for close to 100 watts but powered by a small wall wart of maybe 12 volts and 1 amp at the most and inside the speaker was marked for around 2 watts.

Ralph Mowery wrote: ==================

Except you would have to gullible fool of the decade to believe it.

...... Phil

E = I x R and P = E x I.

If you don't know/understand this, you have no idea of what things are capable or incapable of.

It is not so much the law of P = E x I, but the way it is applied.

There is a 'music'rating for the amplifier/speakers. Seems to sort of being related to radar power. You pulse the microwave device with a few micro seconds of power several times a second and get a peak power of many thousand of watts, but the average power is just 10 watts.

That doesn't mention pigeons or birds. I vaguely remember there was a connection to the need to clean out the horns, but it would seem to be irrelevant since they would have detected the radiation anyway.

Ah, maybe the pigeon s*it angle is a physics equivalent of an urban myth. I believe it was the temperature spectrum of the radiation that had to be determined, but I may actually read that article...

The excess noise measurement came first. Then Penzias and Wilson started looking for any possible terrestrial noise sources. Bird droppings are a lossy dielectric among their other less pleasant properties, so P&W cleaned their horn antenna carefully, calibrated the receiver, and so on, but the noise was still there.

There's still science today that's done that carefully, but I fear it has gotten a lot less common. (Certainly the quality of papers I get sent to review has tanked in the last 25 years or so--and yes, it's the same journals.)

Cheers

Phil Hobbs