[Elecraft] K3S Initial setup calibration problem

[Don Wilhelm]

Tom,

Have you checked that external wattmeter at 5 watts?
Many wattmeters when on the 200 watt range may not show any significant 
output until you get to 10 or 20 watts.

Use the 20 watt range on the wattmeter - and do not really trust it at 
the 5 watt level.  The diodes in many wattmeters are a potential problem 
and may not register anything unless the power is 10 watts and above. 
The exception is QRP wattmeters with op amps and compensating diodes.

If you have access to a 'scope with a 10X probe, that is more accurate.
Set the scope to read the RF voltage and connect it across the dummy 
load.  If your dummy load does not allow access to the coax center 
conductor, use a Tee adapter to access the center conductor.
The RF peak to peak voltage for 5 watts is 44.7 volts.

Bottom line - do not trust your instruments (wattmeter in this case) 
until it is proven trustworthy  at the power level involved.

73,
Don W3FPR

On 12/16/2017 6:20 PM, Tom Norris wrote:
> Newly assembled working great so far.
> At the Owners Manual Calibration Procedures pg 52 (Fred Cady book Elecraft
> K3S and P3 referred me to Owners Manual for some Calibrations after going
> through Configuring the K3S pg 26...)
> Wattmeter:
> Both CONFIG:TUN PWR and PWR SET to NOR (KPA3A not installed yet, all covers
> on.
> Low-Power (5 W) W mtr calibration
> On 20 meter band at 14.050
> On a 1kw Cantenna 50 ohm dummy load (ch'd w/ Ohm meter)
> Set power to 5.0 watts on K3S with Pwr knob
> Go to CONFIG WMTR LP showing
> Press TUNE (hear signal on Omni D) but does not register on ext W Mtr and
> cannot vary output with VFO A knob (which is the instructed 'Parameter'
> adjustment knob I assume?)
> Ext W Mtr is working ok with Omni D output