02 February 2014

Building a Bench Frequency Counter

Ok, so here's a radio post.. well sort of.

I have been servicing my old Ham Radio gear and found I really needed a Frequency Counter to help me sort out drift problems with the VFOs.  Anybody who reads the RSGB publication Radcom, will know EI9GQ's articles Homebrew.   One of these was a frequency counter based on a pretty simple PIC circuit - so I decided to give it a go.

The hardest part in the end was getting the PIC programming software (pikdev.free.fr) running on my Ubuntu PC and talking correctly to the serial interface for the programmer.  But after some great help from a kind Frenchman, I did get that part working - all a bit strange to start with as I haven't worked with a PIC before.

The picture below shows the completed counter circuit connected in this case to a test crystal oscillator. (So thanks also to EI9GQ for those great articles.)

The next problem was getting the counter calibrated. Following EI9GQ's suggestion, my aim was to use the Russian frequency standard transmissions on 9.996MHz as my reference, and then sync the test oscillator to that.  With no general coverage receiver to hand, I used a combination of WEBSDR and a simple computer spectrum analyser to identify the Russian transmission and sync up the test oscillator. I think I managed to get it to with about 20Hz or so, which is not a bad start.

Just need to get it boxed now....

03 March 2013

Installing JMRI on Ubuntu 12.04

Ok, this is as much for my benefit as anybody elses, as having spent quite a time trying to get JMRI running properly on Ubuntu, I feel I should record what the solution was, so I can do it again if needed...... done I must add with a lot of help from the guys on the JMRI Users Group.

 Maybe it will be useful to others, who knows.

Step 1. Ignore everything on the jmri.org website.

Step 2. Install the latest Java relaese by following the steps on this website.

Step 3. Download the newest release of JMRI from here Unzip it to somewhere you'll remember.

Step 4. Add yourself to the 'Dialout' user group:
sudo useradd ralph dialout

Step 5. Make sure you have the correct permissions to access the serial ports:
sudo gpasswd -a ${USER} dialout

That should do it!

For one step better refined, create a desktop icon that will launch the JMRI app you want - DecoderPro3 in my case  (thanks to Dave from Australia on the JMRI Users Group):

[Desktop Entry]
Name[en_AU]=DecoderPro 3
Comment[en_AU]=JMRI DecoderPro
Name=DecoderPro 3
Comment=JMRI DecoderPro

The above works for JMRI located in a JMRI folder in /opt (and you'll need root permissions to do that). Save this text as a file in /usr/share/applications.  You should then be able to drag it to the Unity launcher and off you go.


Runs a whole faster than it did on Windows too.

09 February 2013

After a couple of winters with lots of sunshine and not so much snow, it is nice to have such a long spell of proper winter weather - and Rory the Golden Retriever thinks it's the best time of year. Forecast is for another dump Mon/Tues, so looking forward to some more good skiing later in the week.

06 February 2013

Wow - finally made it back in. Had real problems getting the password reset actions to work..... So, time now to start resurrecting this blog I think.

24 August 2010

Where've you been?

Yes, ok, it has been a long time since we made a post. No excuse.

We are now in the thick of peak season though, so perhaps it is not hard to understand.

It's been a good summer here - or I should say, it is a good summer here, as it is by no means over yet. A lot of hot sunny weather in the Slovenian Alps. This year though, we have not had the regular and spectacular thunderstorms of last year, which is a pity. It has also made it much harder to keep the water butts filled up, badly needed for watering all the flower troughs.

On the plus side, all the fruit trees are heavily laden this year, much more so than last. Plumbs anybody? There's going to be a lot of them.

So hopefully won't so long 'till the next one.