Heathkit DX-60A (part 2)

Waters Dummy Load - Wattmeter and DX-60A producing power
Waters Dummy Load – Wattmeter and DX-60A producing power

Getting ready for the serious RF and insuring that both the band switch of the DX-60 and the VFO were both set to 40 meters, I placed the meter switch in the PLATE position, set the Mode switch at first on AM and then to CW and using the Tune and Load caps, I was able to find a dip in the Tune and started increasing the Loading -always maintaining a resonant condition. Noticing the meter on the Waters, I saw the power starting to increase slowly (which is what I was aiming for). It initially read 12 watts and slowly increased to 35 watts. I kept taking rest periods as I was not confident of all this loading on the final (6146) and on the high voltage plate circuitry. Continuing on, I managed to get the Plate current to a resonant 100 mils  (which was a very low current according to the manual)but the power output was at 60 watts which is about the normal power out for this rig. My best guess is that the metering circuitry is off (for whatever reason) but the proof of the Drive and Final Amplifier circuitry is in the resultant output. Wow, really was not expecting that much power!

The Heathkit Lineup -  SB-303 receiver, HG-10B VFO and DX-60A transmitter.
The Heathkit Lineup – SB-303 receiver, HG-10B VFO and DX-60A transmitter.

My next task was to ensure that the signal that was being produced was a clean, stable and acceptable signal. Initially I would listen on my Icom IC7600 with no antenna and the attenuation fully on. If I tuned the receiver to a frequency 75 or 100 kHz off the transmit frequency, I knew I would be able to locate the signal on the scope of the 7600 and if it appeared too large I would not monitor it for fear of receiver overload. I packed up the rig, brought into the shack and started to connect the required cables and my paddle. Since I was not going to use my straight key or one of my Bugs, I decided to use the new Begali paddle I had purchased in May at Dayton. Since these old rigs did not have a built in keyer I would utilize my K1EL Winkeyer to key the rig which provides for grid block keying. With everything connected and my Steppir Yagi tuned for 40 cw, I set the grid drive to 2.5 mils and started loading the antenna. At 12 watts I could see the signal on my IC7600 Spectrum Scope and it was not a tremendously strong signal so I tuned the receiver to it. The sound seemed pure, the frequency was stable (I had warmed it up for over 1/2 hour) and I could not detect any key clicks or a chirp. I also monitor my RF output of my station through a Wavenode RF sensor. This sensor has a pickup that allows me to feed the signal to my oscilloscope and monitor it (I usually monitor my SSB waveform  to ensure its linearity) but I am also able to monitor the CW waveform. As my Winkeyer was running my stored CQ, I watched the CW trace on the scope. The envelope looked great- clean and even through CW pulsing. So far, so good. The next item I needed to accomplish was an actual CW QSO. So I made sure that my SB 303 receiver was on frequency and started calling CQ on 7027 Mhz. I was sending at about 27 to 29 wpm but not getting any responses. Uh oh!

TO BE CONTINUED……..