I spent the day designing and building a RF Line Sampler for my new oscilloscope which will be used to monitor transmitted signals. I built a simple 10:1 resistive divider in a box which is inserted in the feedline. I used 100k/10k resistors which seem to give good results at these power levels.
The transmitter is putting out a string of dots at approximately 1000W into a 50 ohm Dummy Load.
This is a close up of the oscilloscope screen.
The keying looks a bit hard, the trailing edge in particular, I would appreciate it very much to receive reports on the quality of my CW signals.
I have performed the Key Click modifications on both my Yaesu FT1000MP transceivers, and I believe they are as clean as they can be in this respect.
The scope is triggered by simply feeding the combined keyer signals to the B input and selecting the B channel to act as trigger.
The result is that there is no display on the scope until I touch the paddles or generate cw from the logging program – the scope then shows a stationary display of the RF envelope, which enables accurate measurements of delay times and sequencing can now be adjusted to perfection.
The scope is showing the RF envelope of 1KW with a string of dots at 50WPM.
I have now made some measurements and adjustments to the sequencing. The CW rise time of my Yaesu FT1000MP MK V measures 6mS, the decay time is 4mS. I adjusted Menu setting 7-4 Bk-in-time = 10ms, Menu setting 7-5 Keyer Delay to 0.10 (10mS). Sequencer settings are PTT= 10mS, CW=10mS, PreAmp=20mS, LINEAR=10mS…..
PTT delay in Win-Test was set at 10mS.
The radio with the linear amplifier is now incredibly smooth and responsive, I have never experienced anything like it before.
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