[Elecraft] Test Equipment Procedures

[Don Wilhelm]

Roy,

You should be able to measure the RF output waveform directly with the
'scope.  Connect a 50 ohm dummy load to the K2 antenna output and connect
the 'scope probe across the dummy load.

To measure power, use the basic formula P = Vrms*2/R
     Your 'scope will easily show you Vp-p, so you must convert your reading
to Vrms before   applying that formula.  If you juggle with the formula for
a 50 ohm resistance and RMS to PEAK conversion, you will find that the
formula becomes P = (Vzero-p)*2/100 so for 100 watts out, you will see 100
volts zero to peak or 200 volts peak to peak.  For 5 watts, you will be
looking for 22.36 volts zero to peak or 44.72 volts peak to peak.

While the 'scope is connected to the dummy load, you can look at the keying
waveform directly - just set the time base and triggering to give you a nice
stationary RF envelope display.  Similar for the SSB envelope, but the SSB
pattern will not tell you much unless you feed the audio with a 2 tone
signal.

For those not having a 2 tone signal generator, you can use the sound card
output from your computer.  Load and start one of the PSK31 programs, set it
to transmit and it will send the idling tones (which is a 2 tone signal).

73,
Don W3FPR

----- Original Message ----- 

| Ok guys, I got this great Tektronix 200mhz scope, 250mhz probes, a
Tektronix
| freq meter and a K2/100 working FB. I want to check #1 power output #2 SSB
| envelope #3 CW waveform #4 output freq and I want to do this, if possible,
| using 5 watts and 100 watts. I also don't want to damage my test equipment
| or my K2/100. I'm looking for ideas on how to connect the test equipment
and
| scope setup.
| Thx
| Roy Vickers (KF5YU)
|