[Elecraft] P3 New LVL Cal Function (Beta 0.41)

[Amateur Radio Operator N5GE]

Thanks, Bill!  I printed the instructions and will try it later today.

73,
Tom
Radio Amateur N5GE
QCWA Member 35102

On Thu, 11 Nov 2010 03:18:25 -0800 (PST), Bill W4ZV <btippett at alum.mit.edu>
wrote:

[snip]
>Al must have forgotten to include the instructions.  The following is
>PRELIMINARY ONLY but should get you going:
>
>Amplitude Calibration
>
>The P3 comes with a default amplitude calibration that works well with a K3
>transceiver that either was manufactured after approximately 9/1/2009 or, if
>an earlier unit, has the IF output buffer gain modification described in the
>application note on the Elecraft web site.  If you have an earlier unit
>without the modification, or you are using the P3 with a different model
>transceiver, or if you just wish to obtain better amplitude accuracy on the
>P3 display, you can do the following calibration.
>
>The recommended test frequency is7040 kHz at a signal level of 50 microvolts
>(-73 dBm) using a calibrated signal generator such as the Elecraft XG2. 
>However, any frequency and power level within the range of the transceiver
>and P3 display will also work.
>
>* Make sure the the P3 IF IN is connected to the transceiver IF output.  If
>the transceiver is a K3, connect the RS-232 cable as well.  Turn off the
>preamplifier and attenuator on the K3.  If you have the KRX3 installed, make
>sure SUB is disabled.
>
>* Connect the signal generator to the transceiver antenna input.  If it is a
>K3 that includes the KXV3 or KXV3A option, it is best to use the RX ANT IN
>connector to eliminate the possibility of damaging the signal generator if
>the K3 transmits accidentally.
>
>* Set the signal generator for 7040 kHz at a signal level of 50 mV (-73
>dBm).
>
>* Set the SPAN on the P3 to 100 kHz, and tune the transceiver to
>approximately 7015 kHz so that the signal is centered on the right half of
>the display.  Set the SCALE to maximum expansion (10 dB) and adjust the REF
>LVL to about -78 dBm, in order to place the peak of the signal about half
>way up the screen.  You may notice a slight variation (~1.5 dB) in the peak
>signal level with small adjustments in the transceiver frequency, as the
>signal is tuned from pixel to pixel across the display.  Adjust the
>frequency for a maximum reading.
>
>* Tap MENU, select Lvl Cal, tap the knob, and adjust the level calibration
>until the signal is at -73 dBm on the display.
>
>You can also calibrate a receiving or transceiving converter, either the
>K3's optional internal K144XV or an external device.  If you plan to do the
>above calibration on a standard frequency, do it first since that
>calibration is added to the converter calibration.
>
>* Set up a signal generator, the transceiver and the P3 in a manner similar
>to the above to obtain a signal near the center of the right side of the
>display and approximately centered vertically, with the P3's SCAN at 100 kHz
>and the SCALE set to 10 dB.
>
>* Tap MENU, select XV Gain, tap the knob, and adjust the knob to select the
>desired converter band, 1-9.  Tap the knob again and adjust the gain on the
>selected band so that the signal is at the the correct level on the display.