It depends on the wattmeter. If the wattmeter had a PEP or peak-hold
mode, it would show the actual peak power. Many simple meters are
There are a number of meters on the market that show peak power. One you
latest QEX. You can read more about it and the simpler LP-300 kit on my
website... link below. They are both digital with peak-hold, but also
>-----Original Message-----
>Matt wrote:
>
>I'm a little confused about measured transmitted power when in SSB vs CW.
>
>As an example, I have an XV50 Transverter that is adjusted to produce 20
>watts RF out when using the K2 'tune' control. This output is adjusted by
>reading 20 watts on an external power meter. The power indicator LEDs are
>then adjusted to read 20 watts as well.
>
>When using SSB, however, the RF out is much, much lower, maxing out at 7-8
>watts PEP on the external power meter. The indicator LEDs, however,
>indicate 10 - 20 watts of power.
>
>I'm not certain I know how to understand what it is I'm measuring. In my
>mind, I think much the 20 watts RF out of a CW signal is actually carrier
>and of not much use. When in SSB, I want to think that I can still put out
>the 20 watts, only now all concentrated in one sideband.
>
>Why does the power meter fail to show the 20 watts?
>
> _______________________________________________
>
>Of course CW is ONLY carrier, on and off, so the information is in the
>keying. But when the key is down, you are putting out full power.
>
>Your transverter should be configured to put 20 watts out when driven at
>either 5 watts or 1 mW, key down in CW mode, depending upon whether you have
>the K60XV interface installed in your K2 and are using the RF output at the
>antenna connector or the K60XV connection.
>
>When your K2 is in TUNE, the power is reduced and no longer controlled by
>the K2's automatic power controlling system. That's so you can tune up with
>an ATU and the K2 won't go nuts trying to adjust its power output as the SWR
>changes. If you set up your transverter for 20 watts output with the K2 in
>TUNE, you may overdrive it in normal operation.
>
>SSB has a very low duty cycle. That is, the average power output is far, far
>below the peaks. You can raise the average power a bit using the K2's speech
>compression, but its average is still well below the peak CW level. The very
>brief transient peaks in your voice will hit full 20 watts out and unless
>your Power meter is designed to register peak RF and not average RF (like
>most meters) it'll show a much, much lower RF AVERAGE output even though
>your voice peaks are hitting 20 watts. The LED display on the transverter
>(and K2's RF bargraph) show the actual output, so you'll see them both
>flicker on voice peaks.
>
>Ron AC7AC
>
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