Sunday, March 24, 2019

KFF-3056 activation report

2.5 watts from the KX2 drove the HR-50 to 42 watts out with 12.5V battery

Today's activation of Sheldon State Park (KFF-3056) just east of Houston went well and resulted in a lot of fun contacts. And I did my best not to annoy the alligators.

Camera tripod on car top supports 17' whip
The main purpose was to test my Hardrock-50 amplifier on battery power to see just how much capacity an hour or two would require. For 40 contacts over a two hour period, the HR-50 used 4.4 amp-hours of juice. Less than I would have thought.

On receive, the amp draws 230 mA; on transmit - about 7 amps. This is with 2-1/2 watts from the KX2 driving the amp to 42 watts of output.

Power was supplied by an automotive-size deep cycle battery and was about 12.5 VDC. The KX2 was powered by a separate battery. From this, I'm guessing that an 8- or 9-AH battery would provide power to both the KX2 and the amp for two hours with capacity (or time) to spare.

Prior to getting on the air I went into the KX2's menu and set ATU-MD to 'BYP' to bypass it since I would be using the autotuner in the HR-50.

The antenna was a 17-foot telescoping whip attached to a camera tripod with a vise-grip mount that has fittings for a 3/8" antenna thread and an SO-239 connector - a handy gadget that stays in my car. I put the tripod on top of my car and laid out two 1/4-wave radials in opposite directions from each other. All contacts (except the last one) were on 20m, and all but two were CW.

Highlights of the activation were working my friend and outdoor QRPer Jim W1PID up in New
I drank Gatorade to act as repellant
Hampshire and also working XR0ZRC.

Jim posts write-ups and photos of his QRP excursions here. They are fun to read, especially when the summer heat keeps me indoors during our long summers. We've worked each other a number of times with each of us in various locations on all but two of the HF bands. Always a pleasure, Jim - thanks!

XR0ZRC was on 15m operating from Juan Fernandez Island and listening 1 up. I couldn't hear the stations he was working but I put the KX2's B-VFO up about 1.2 kHz and got him on the 4th call. His signal was quite strong and I knew I had a good chance of being able to work him.



  1. It was great to hear you out there this morning. There was one moment when you went from 339 to a solid 589 in the space of 3 seconds. Thanks for being out there

    1. I think that might have been due to the interface board coming loose from the connector on the back of the HR-50. On 3 occasions I had to re-seat it when I noticed the amp wasn't being keyed. I need to look at a way to have it more securely attached.

      73 - John