HamRadio Exibition

A few impressions from the HamRadio 2016 in Friedrichshafen. The spiderbeam antenna behind my VW camper unfortunately belongs to the neighbor 🙂

The Kenwood TH-D72 radio will have a successor. It’ll become available end of 2016. Added features are D-Star, SSB (rx only), color display, 220 MHz option (probably not in Europe).

Sometimes I’m thinking that if I didn’t spend my money on all the cheap radios and parts, I might have been able to afford a Hilberling already.



Grossfunkstelle Nauen

I recently passed by the first and biggest commercial radio station Nauen in Germany (not far away from Berlin). From here the first German trans-atlantic contacts were made. The hight of each of the four rotating antennas is 80.5 m (264 ft). There is a smaller rotating antenna nearby which seems to be out of order, but you can have a closer view at it.

First SSDV Floater

It took us about half a year to develop a float capable camera tracker, but now it’s real! We’re just observing the first ssdv pictures coming in and (almost) everything works great. The total weight of the hardware (including 8 solar panels) is just below 30 gramm. We have chained 3 Qualatex 90 cm diameter balloons in a row and each of them has 14.3 g lift. This leaves us with about 9.5 g free lift (considering the tape weights 3.5g which we used to glue the ballons together). Due to some wind in the morning we had a hard time to clear the houses and trees at launch, but eventually we succeeded.

Life tracking & SSDV Links:


Wow! Munich International Airport.

Pecan Pico 7 (“Pecan Comfort”)

Have you ever dreamed of a pico balloon floater tracker with a camera & SSDV? Do you want a crossband repeater? Want enough power for the ISS to post your positions on ARISS? I have pushed Sven (DL7AD) to design such a dream tracker based on a STM32F429 BGA version. His result is truely amazing. We’ve received the PCBs and the stencil two days before Christmas. We didn’t have all components in stock, but we tried to build a development model for the lab so that we can start testing. Basically the power regulators are missing, but we can supply the needed voltages externally from the lab power supply. Initial power up testing was successful. Let’s see how programming will work…


Total weight: < 6 gramms

Documentation and software development at Sven’s GitHub:

Small Tracker – Big Balloon

This is our first launch with a Pecan Femto 3 tracker. With broken off pin header the weight of the complete PCB is 0.91 g (0.032 oz). However there is a big LiPo battery (11.5 g, 560 mAh) on board this time. The total payload weight including solar cells and mounting was 14.34 g. The balloon was custom made by Uta (1.40 m x 2 m). Total lift 12.3 g. Track DL7AD-12 in aprs.fi or at tracker.habhub.org .


During the night the temperature dropped below -52 degrees Celsius. Obviously the LiPo battery didn’t make it and first the GPS stopped and later the transmit ceased entirely. We were lucky enough that the balloon came back to life in the morning at rising temperatures. We were happy to observe a further ascent up to 14.5 km altitude. The balloon appears to have a tiny pinhole because it slowly descended and landed in the mine fields near Sarajevo (Bosnia Herzegovina). Do not recover this payload!

Pecan Femto 3

Sven (DL7AD) has designed another miniature tracker board and we have soldered two PCBs last week. We have still two minor hardware issues that could be patched and the software needs to be re-written due to the new micro-controller. Current state is that on one board the GPS is unresponsive and on the other board the transmitter is broken. However that’s enough to work on the software for now. We’ll solder up some more boards next week and hopefully we’ll get a full working tracker soon.