Akademisk Radioklubb

LA1K / LA1ARK / LA1UKA

Author: LB0VG

Updates on the SSTV project

After a long break, Henrik LB5DH and I decided to start working on the SSTV project again.

This time we wanted to look on how we wanted to mount and secure the antenna up on the roof.

Handmade foot

We found an old foot on the loft, which seems to work well for our installation.
We later found that we could rest the antenna on the roof without it, but in the finished installation we will be sure to make use of it.

The antenna after taking it down

The mounting solution

For mounting the guy wires we drilled two holes through the pipe on the opposite sides of each other.
This way we got four points for securing the mast. Luckily we already had structures on the roof to secure it to.

Temporary length of wire added

The issues came when trying to tune the antenna. Even though the antenna tuned fine inside, it gave us different results with the best SWR around 100Mhz when we took it outside.

This drop was the closest to 1:1 ratio we could find.
We tried adding more spools, extending the wire etc with not too good results. We did have a drop at about 3-4 in SWR around 10-11Mhz, so we seem to be close.
It does seem like the antenna isn’t reading it’s full length, so we’ll have to do some more calculations before proceeding with mounting the antenna.

We’d also like to mention that the SDR dongle has arrived, and initial testing has showed us that the direct sampling technique will work adequately for us.
More info about this and the antenna is coming soon!

-LB0VG

NRRL Vintertest 2017

This weekend LA1K participated in the Norwegian contest ‘NRRL Vintertest 2017’.

The first two stages gave rather disappointing  results due to poor conditions and interference on the audio equipment in the building, but the third and final round gave us a nice score overall.

This was the first contest we’ve had with our Flex 6500 and we are more than happy with the results so far.

Henrik, LB5DH og Kristin, LB2NH kjører 40m

Henrik LB5DH and Kristin LB2NH on the 40m band

Mats LB0HG

Mads LB0HG on the Flex 6500 during the contest

Thanks to LA1BFA, LB6RH, LB0HG, LB5QG, LB5DH, LB2NH, LA2QUA, LB7RG,  LB7JG and LA3WUA for participating.

Flex 6500

After a long wait, we finally received our sample of the Flex 6500 this Wednesday. This was purchased as a replacement of our 756 Pro III as it has reached 10 years of use, and therefore will be put to use as our HF-radio number 2.

The package included a quick start guide, a CD for the SmartSDR software, a power and Ethernet cable and a FHM-2 microphone.
Flex 6500 radio

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SSTV decoder project

Henrik (LB5DH) and myself (LB0VG) are building a “fully” automatic SSTV decoder to be put up permanently in our club. The biggest part of this project is building an antenna from scratch.

The goal of the project is to have a SSTV decoder that in theory can be online 24/7 for displaying decoded pictures in realtime. In addition, it is also a rough way to display propagation for the 20m band. This will hopefully drive more attention to SSTV so that our club can become more active on digital modes.

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Lisenskurs

Akademisk Radioklubb are having a course in amateur-radio. The goal of the course is to undertake an exam, and if passed – recieve a callsign. The course starts Wednesday 08. of February, and will continue 4 or 5 evenings during February/March. There is no fee to the course, except a one-time fee for the license itself. We encourage everyone to participate in the course.

The course is held at Gløshaugen, classroom B22 from 6 to 8pm.
http://s.mazemap.com/2kkS5x9

The final summary and exam will be in week 10, further details will come soon.