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UV-shieldA few weeks now I run my own weather station, a Ultimeter2100 from Peet Bros. At least once a day I check my weather data against that from the neighboring Royal Dutch Meteorological Institute (KNMI). It turns out that my temperature readings are off a few degrees (too high) only in the morning. Which is not surprising when you consider my temperature sensor is attached to our chimney. This turn out to be the only place that has shade almost all day. Almost… But not in the early morning (only if the sun shines).
It seems I’m in need of a UV-shield for my temperature sensor. After visiting the local DIY-shop I sawed, I glued and painted… Some people asked me if I had build me a nice bird-residence, but no. It is an UV-shield! It’s a familiar construction for this application: because the strips overlap each other, the sun can not shine between. But the air can flow freely around the sensor. Which has two advantages: no warming up of the sensor by sun rays and no fast cooling down by water drops on the sensor when it rains.
My second comparing of data turned out way better, my UV-shield seems to work.

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second TM-D710After I bought my first Kenwood TM-D710 in 2012 I discovered this was the ideal rig for me, mobile as well as stationary. I use it primarily in the shack and took it with me in the car when went mobile. I figured it would be convenient to have a second TM-D710 main-unit in the car, then I only have switch the front panel between shack and car. In order to help me trace a second TM-D710 unit, I set a Google Alert on Kenwood TM-D710.
Forget totally about this alert until a few weeks ago I received a mail there was a new entry for my search term. I clicked it and it was an ad on a local sales site. After a short bid I got a message from it’s previous owner Rudy PD1RVM. So a long story short: a few days later my second TM-D710 arrived. It was still in it’s original box and in mint condition. After some short tests the rig seems fine and I had to determine which one to put in the car and which one stays in the shack.
I did some modifications (adding GPS to the display-unit, swapping the noisy fan of the main-unit). After some thinking I decided to use my old front-panel (with GPS-module) and the main-unit from the second TM-D710(with slightly more noisy fan) in the car. The front-panel of the second TM-D710 went to my old main-unit in the shack. No sooner said then done I tested the config in the car. Worked excellent!
But when testing the setup in the shack, it fails to connect to my weather station. That’s weird! Tried different things but nothing helps. I suspected the GPS-port on the front-panel of the second TM-D710. It had to do something to do with the port. Finally I took apart the front-panel from my old radio, connected the GPS-module to the standard Kenwood wire and connected it to the new front-panel. Indeed, also nothing.
Next step: take apart the new panel and find something blackened. But to my total surprise it wasn’t broke; there was a beautiful build in GPS-module as well! That explains a lot, when there is a GPS-module in it, the serial port is occupied from the inside. I’m never able to see any device I connect from the outside.
Tested the new front-panel in the car to see which GPS-module performed better. No doubt about it: it’s the one in the second TM-D710! It has a fix within 2 second where I had to wait at least a minute for my old GPS-module to get a fix.
Disassembled the GPS-module from my old front-panel and connected the weather-station again. Now it plays immediately.

Now I’m a proud owner of two TM-D710’s. One for mobile and one for my shack.

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Double quad 23cmWith the 23cm transceiver still in development, I need a 23cm antenna. I got interested in a double quad for 23cm.

Advantage of a double quad for 23cm over other designs is a great front/back-ratio and a large opening angle. I will use the 23cm transceiver mainly for chatting on a local repeater PI6NOS. There is a free-line-of-site from my roof to PI6NOS. No need for a huge gain to open the repeater. I’ve chosen a fixed antenna position.

A few guys at my local club build a 23 cm double quad themselves. It isn’t a very difficult job. Only thing I didn’t like about it is it has to be placed in a plastic container to be weather proof.
Last radio market I attended I walked by a stand of EPS-antennas. The owner Paul PA3EPS, builds beautiful antennas for HF and higher bands. In his line-up Paul PA3EPS sells a double quad for 23cm. It’s a bit pricey in comparison with DIY. But then again, if you focus on construction, used materials and the fact that is weather proof as is…. anyway,it wasn’t a difficult choice. I prefer excellent quality antennas on my roof in order to avoid unnecessary presence there. That has something to do with a fear of heights.

Before I attach the EPS double quad for 23cm on its final position in the mast, it might interesting to see if there is a significant difference in performance between the DIY double quad (not yet tuned) and the EPS double quad. Unfortunately I don’t own much measuring equipment for 23cm so the only way to roughly compare the two is to check the signal of PI6NOS on my 23cm transceiver with both antennas in the same place, connected with the same cable.
The result you can see in this video.