Category Archives: Amateur Radio

Shack 2.0

So, several months later, house move complete and it is time to get a shack operational again.

I am a fan of keeping things running when the power goes out. From a Amateur Radio Communications perspective, I have had a 80Ah battery in the shack for over 10 years and I have been using a West Mountain Radio Super PWRgate PG40S and Rigrunner 4010S to power my radio equipment and to keep the battery charged. My current ‘desktop’ is based on a Intel NUC 7i7BNH these along with their LCD’s are running off an older APC Smart UPS 1500, which gives between one and two hours of run-time should the power go out.

While everything was in boxes, I purchased a West Mountain Radio EPIC PWRgate (I wonder what adjective will be used to describe the 4th Generation!) this device can charge Lead Acid, AGM/GEL and LiFePO4 Lithium battery types, and, what attracted me to it is that it has a built in Photovoltaic (PV) Charge Controller. Which removes the need for a dedicated Charge Controller.

Sometime during the move, the old AGM battery died (Ophelia was its final ‘performance’). New shack, new battery, a Trojan EverExceed ST-1280 was ordered from O’Connell Batteries in Cork and duly arrived.

Plug-and-play? well not-exactly. After looking at the specs, the default ‘AGM’ setting in the Epic PWRgate needed some adjusting to avoid overcharging the battery. The battery specifications say 2.35 Volts per cell (for 12 hours), so the ‘Max charge voltage’ needed to be dropped from 14.4 to 14.1 volts, and the PSU set to 14.2. On Linux, the Epic PWRgate appears as /dev/ttyACM0, guessing I used 115200, N81, no handshaking and its console immediately popped up.

Battery:  1-Disable, 2-Gel, 3-AGM, 4-LiFePo4, 5-Other:    <3>: 3                
Reset to default values (Y,N):   (Y,N) <Y>? n                                   
Max charge voltage in Volts:    <14.10>:                                        
Max charge current in Amps:    <10.00>:                                         
Min charge current in Amps:    <1.00>:                                          
Trickle current in Amps:    <0.25>:                                             
Recharge voltage in Volts:    <13.49>:                                          
Max charge (minutes):    <720>:                                                 
Retry after abort (minutes):    <240>:                                          
Min supply voltage for charging in Volts:    <14.15>:                           

Once out of setup mode, it spits out readings about once per second. This includes what the state of the chargers is, the power supply voltage (PS), Battery voltage and charging current (Bat), Solar Panel voltage (Sol), Number of minutes in this charging state (Min)

 Trickle   PS=14.22V Bat=13.61V,  0.05A  Sol= 0.04V   Min=962  PWM=337  adc=6                                                    
 Trickle   PS=14.22V Bat=13.61V,  0.05A  Sol= 0.04V   Min=962  PWM=338  adc=6                                                    
 Trickle   PS=14.22V Bat=13.61V,  0.05A  Sol= 0.04V   Min=962  PWM=339  adc=6                                                    
 Trickle   PS=14.20V Bat=13.62V,  0.05A  Sol= 0.08V   Min=962  PWM=339  adc=6  

Hopefully the battery is as reliable and lasts as long as the last one!

EI7CDD DMR Repeater, Retevis RT8 and GPS functionality

Last week, I gave a short talk on DMR and Brandmeister at the South Eastern Amateur Radio Group club meeting. There were quite a few members present and there were plenty questions.  The full presentation is available from here, but what is new (since the IRTS AGM presentation) is this image taken from Xastir.


This is a track formed by a numberof GPS position information beacons from my Retevis RT8 Radio, the data bursts are received at the EI7CDD DMR Repeater, and then forwarded to the worldwide APRS Internet Service backbone before appearing on the map.

What is interesting to me is that the RT8 was just thrown on the dash of a van, no special effort was made to optimise its position, the terrain is by no means flat, undulating would be the best description, and yet, the RT8 was still able to hit the EI7CDD repeater from up to 20k away.

EI7T at Ballinacourty Lighthouse

Late last year, it was suggested at a Tipperary Amateur Radio Group club meeting that we should do something ‘different’ in 2017.

The suggestion was made to Activate a Lighthouse for the International Lighthouse and Lightship weekend.  Given the lack of lighthouses in Tipperary, I made the suggestion that we use Ballinacourty Lighthouse.  I had assisted EI2GN with an activation there years before and my recollection was that it was quite accessible.

Due to work commitments, I was late down to the site so kudos to EI3ENB, EI2HI, EI4KN and EI5JF for getting everything set up.  I thoroughly enjoyed the operation before I had to head away again.

Andy, EI5JF, made a short film (and took some pictures) of the operation, which isn’t too bad considering the material he had to work with!

Certificate surprise!

I got an email from my better half this morning asking me what deliveries I was expecting as the postman had left a note.  I couldn’t think what it could be and quickly forgot about it.

Much to my surprise, this it was is was…

Shadow-beacon experiment
What a lovely certificate for my (fairly minimal) participation in the experiment.  In fairness the photograph taken with my phone does not do it justice.

APRS activity in Ireland

In a conversation  late last year (at the TAPR DCC)  I was asked what is the actual level of APRS activity in Ireland.  Thinking about the answer for a while, I realised that I really didn’t know, and that got me wondering how to go about visualising it.

I quickly came across  Leaflet.heat, a Leaflet plugin plugin for generating heatmaps, so I  bodged together some python to grab packets of moving stations from the APRS-IS backbone and put them into a format Leaflet.heat can read.  After gathering about 6000 data points, here is what it looks like:

So, there you go, it is fairly conclusive that Cork city has the most ‘on-air’ APRS activity. This is followed by Waterford area, Galway area and then the main motorways.

Ham Radio… Now What?

I was looking for something to watch/listen to while tidying up my inbox today after being away for three weeks or so.  We took in the ARRL/TAPR Digital communications conference while in Florida. As I enjoyed this years DCC so much,  i went looking for last years DCC banquet speech.  Ward Silver, N0AX, gave an excellent talk on the direction the hobby should take for it’s second century.  I particularly liked his comment about contesting and being “able to heard the world turn”. Thanks to Gary Pearce, KN4AQ for attending the DCC and working so hard to make the videos available (feed the pig!).

SSB Field day 2015

Last weekend, I joined other members of Tipperary Amateur Radio Group on the farm of Paul, EI3ENB for the SSB Field day.

EI5HBB operating
EI5HBB in Search and Pounce mode.

40m and 80m Dipoles, with the Tribander at the left of the picture.

Unfortunately we weren’t able to get any decent runs going on 20m or 15m which would have helped our score quite a bit, however Eoghan, EI5HBB was at the microphone when we got a decent run on 80m for about 90 minutes in the early hours of Sunday morning.


EI7IG's suite
My comfortable accommodation for the night.

Looking forward to next year already!