RaDAR – Equipment and purpose

Once again my amateur radio equipment has been refined keeping the purpose of minimalistic RaDAR in mind. I now only have a few rigs – each with a purpose.

B25 Ex-Military HF only radio – I use this radio at home running off batteries. It can easily be packed and transported to an alternative QTH. Although it was initially designed as a manpack for the military, it’s pretty heavy to carry. I use two 7 A/Hr SLABS wired in parallel as a power supply.

Smart Charger – Needed to charge sealed lead acid batteries (SLAB’s). No other charger is suitable. This charger ensures a decent charge without damaging the batteries.

HB1A CW Only 40m/30m/20m QRP radio – This tiny radio works well and although it was designed to be trail friendly I use it at home for ad hoc CW contacts from home. I use it with various hand keys depending on my mood or a Bencher BY-1 paddle for faster speeds. This radio always impresses me for it’s simplicity and what it can do. It has excellent audio!

40m End fed tuner and 20.2m long wire – My antenna of choice for 40m communications from home. Pretty slealthy too so it doesn’t attract any complaints and works extremely well. The tuner is fixed outside and fed with ten meters of LMR400 coax (It’s what I had).

TH-D7A(g) dualbander – This is the radio I use for duplex FM satellite communications and APRS. I use the plug in mic and headphones. APRS isn’t that popular in South Africa so it is seldom used. I power the rig externally using 12 x NiMH rechargable penlights which is a cheap and reliable solution.

Garmin Legend GPS – Used occasionally with the TH-D7A(g) for APRS or carried in the backpack for reliable navigation in unknown areas.

Philips MP3 recorder – Used together with the TH-D7A(g) for recording the fast exchanges while doing RaDAR SatComms.

YOTA 2018 Dualband yagi – Used for RaDAR SatComms while in the field. It’s compact and very lightweight. Designed and built in South Africa.

Arrow dualband satellite antenna with built in diplexer – Used on a tripod for fixed station RaDAR SatComms

Xiegu X5105 Multimode HF only QRP radio – This radio is a compact solution for RaDAR operations in the field. It excels here but only in the outdoors. It has a built in rechargeable battery and ATU. It has a built in microphone so the plug in microphone always stays at home. The audio quality of this radio leaves a lot to be desired but not quite that noticeable in the field where the wind mostly blows and the sounds of nature take preference. The communications audio with either SSB or CW is quite acceptable. Headphones CANNOT be used with this radio unfortunately the audio quality demoralises the operator!!!

40m to 10m link dipole fed with RG58cu coax and dual painter pole mast – My antenna of choice in the field. Quick and easy to deploy and strong enough to hande moderate winds using bungi’s as shock absorbers.

That pretty much wraps up my amateur radio kit. I am QRP only but from experience there is not much difference between 5W and a 100W if conditions are good. They should be good anyway if any effective communications need to be made.

73 de Eddie ZS6BNE


RaDAR – Feedback on the November 3rd challenge

Satellite passes formed the basis for my time line. I left home, on foot, at 11:00 CAT.

From experience I have learned not to rely too heavily on the satellites for RaDAR contacts during the challenge. Today was no different. As I got to my first destination I put up my link dipole barely two meters above the ground at the apex hanging from a tree branch. I also setup the satellite gear for a pass of SO-50 for 11:29 CAT.

In the meantime I browsed the 40m band and heard Kobus, ZS6BOS on 7.090 MHz calling from SOTA summit ZS/GP-016 at 11:22 CAT. We were both 59, NVIS comms looked very promising for a change! His grid was KG33VV and mine KG34AC18LQ. After browsing again I heard ZS3VDK/P6 also on 7.090 MHz operated by Kobus. I confirmed that I could log both call signs for RaDAR and SOTA. I used the internal microphone of the Xiegu X5105 which worked pretty well! It is no longer nescessary to carry a microphone. One plus point for RaDAR.

SO-50 was about to come over the horizon. I waited, sitting on the ground, my ISS Detector app giving me precise direction and elevation information. It was coming in from the north. I sent the activate tone while it was barely at 5 degrees and amazingly SO-50 came to life. I called CQ for the duration of the pass with no replies. The satellite signal was excellent. I was using my YOTA 2018 satellite antenna and it worked perfectly for RaDAR. Pity there were no QSO’s ….. but I expected that so it was not too much of a dissapointment!!!

Then I went to 7.020 and called CQ using the morse code (CW). Daryl ZS6DLL came back to me at 11:52. I was 559 and he 599 from grid KG44BC. Sean ZS6SR called me at 11:58. He was 599 too. He gave me a 579 from grid KG33GV. At 12:04 CAT I was called by Tom ZS6OMT. He was also 599. He gave me a 589 from KG33NG in Potchefstroom. Forty meters was in excellent condition! This day I felt proud to be a radio ham. Interest in CW amongst quite a few ZS’s was picking up.

Having the required number of QSO’s it was time to move to my next location. I thought I’d pass by and say Hi to my XYL. I shouldn’t have done that, my neighbours were visiting and half way through a cup of coffee and rusks. Trying not to be rude I set up my SatComms equipment under a tree in the garden and excused myself for a few minutes.

AO-91 was coming in from the south at 12:44 and I listened for it’s carrier. Christi ZS4CGR called from grid KG20KF75FF and my new grid was KG34AC19FJ we were both 59 (FM). Tom ZR6TG called from KG33WG, both 59. I heard later that it was his goal to work my RaDAR station so I’m glad that was a success! Then Andre ZS2ZA called from KF26SB. By this time the satellite’s signal was very strong. Then the sat went past the equator and picked up the usual QRM from central Africa and no further QSO’s were possible. Actually I don’t think there was anyone else around anyway.

I joined my neighbours for coffee and rusks. I showed them a video a friend made of my “RaDAR Playground” before we were interrupted by another neighbour. So we sat talking for a while until they left and went back home. I bid them farewell.

So, having only three satellite QSO’s I needed another two. I set up the link dipole in the garden hanging from a tree branch. I called in on the AWA net (Antique Wireless Association) at 14:08 and got reports from Barrie ZS6AJY 559, Andy ZS6ADY 559 and Tom ZS6OMT again (I was in a new grid). The net is a weekly ragchew net not conducive to the rapid style of RaDAR but Barrie asked in CW if I would require individual info or run off. I didn’t want to bother them any further and I had no time to hang around listening to two minute-plus overs. I greeted all and bowed out.

I packed up the antenna having five, plus one QSO’s. In the meantime the XYL had started working in the garden and needed some plants to be planted. I felt guilty and opted to give her a hand. After all there was only another forty five minutes to go and I still needed to walk a kilometer and deploy with the hope of working someone. I’d already seen my friends Sid ZS5AYC and Adele ZS5APT were very weak. Usually forty meters was short skip and a channel into division five but not today.

All in all my RaDAR ops was a success I think. My kit worked and I have proved my decision to sell all my Yaesu equipment, the 897d and 817ND and all the rest for a Xiegu X5105 was the right thing to do. The X5105 performed very well in a RaDAR context.

CW was KING today – I liked that!!!!

73 de Eddie ZS6BNE

My Logbook  – Attached


RaDAR – Ammended rules for 2019 and beyond

RaDAR Challenge – 2019 and beyond

1. Aim

The RaDAR “Challenge” is a unique event aimed at promoting the use of Rapidly Deployable Amateur Radio stations. Categories (Fixed / Field / Moving) may be changed at any time during the challenge. The points system is so structured as to encourage portable RaDAR operations especially moveable RaDAR stations.

RaDAR operators are encouraged to be self-sufficient during each challenge, with not only power supply and communications equipment but food, water, protective clothing and shelter.

2. Date and Time

RaDAR operators define their own operating time schedule. It’s up to each individual to plan his / her MAXIMUM, SINGLE PERIOD, FOUR HOUR ops. He / she should consider propagation with the ultimate goal of inter-continental RaDAR to RaDAR communications in mind. Share your plans with others to try and coordinate times.

00:00 UTC to 23:59 UTC on Saturday 6 April 2019, Saturday 13 July 2019 and on Saturday 2 November 2019. Twenty four hours will give equal opportunity to the international community of RaDAR operators.

3. Bands and Modes

All amateur bands are allowed including cross band contacts via amateur radio satellites. Modes – CW, SSB, FM or any legal amateur radio digital mode. As from 2019 the WARC bands will be INCLUDED. The RaDAR Challenge is not a “contest” as such, it’s an individual challenge.

QSOs via terrestrial FM repeaters should preferably not be used for the purpose of the challenge.

4. Suggested HF calling frequencies

See https://zs6bne.wordpress.com/2013/03/06/radar-calling-frequencies/ for the RaDAR Calling channels, the latest suggested international list of calling frequencies

5. Exchange

The RaDAR challenge requires more than a minimalistic information exchange. Accurate information exchange is considered more important than a large QSO count. Call sign, name, RS (T) report and grid locator. The grid locator of six characters is acceptable but should preferably be accurate to 8 or 10 characters for higher position accuracy (especially for moving RaDAR stations). Various smartphone apps are used for this or pre-planning using maps is an alternative.

6. Scoring (For determining your own success rate)

1 point per QSO. Individual QSOs could be per mode, per band, per satellite, per grid location. If the moving RaDAR station has moved the required distance contact can be made with a previously worked station, again. Suggestions have been made to call CQ including grid location, for example CQ RaDAR from grid KG34acXXyy, to help callers determine whether it is possible for a new contact with a previously worked moving RaDAR station.

7. Categories and multipliers

The following multipliers are applicable to determine the final score. If category / mode of transport changes were made during the challenge, than calculate accordingly.

X 1 – RaDAR Fixed station (in a building away from home)

X 2 – RaDAR Field station (camping)

X 3 – Moving RaDAR station – see modes of transport below.

Modes of transport and required movement distances (moving RaDAR stations only)

Vehicles, motorcycles and motorboats (motorised transport) – 6 km

Bicycles – 2 km

On foot and paddle canoes – 1 km

Wheelchairs – 500 m

Aeronautical mobile stations are considered moving stations and can communicate at any convenient time.

Note : Moving RaDAR stations need to make five QSO’s before moving to the next deployment point, thereafter they are required to move to their next destination. The move needs to cover the required distance before further contacts can be made. This requirement tests the ability to rapidly and successfully re-deploy your amateur radio station. In the case of satellite communications, plans need to be made carefully to ensure you are at your new position before the satellite comes over the horison. This adds to the fun of RaDAR.

If it be gentlemanly to make further QSOs before moving then please feel free to do so but the QSOs in excess of five per deployment point can not be counted for points. Your extra QSO’s may well help others to achieve their QSO count. Help your fellow ham to achieve his / her goals if the opportunity presents itself.

8. Bonus points (All categories)

Five (5) points for a minimum of one satellite OR digital modes QSO involving a computer, smart phone or digital modes device. (For clarity thereafter 1 point per Satellite / Digital modes QSO).

Five (5) points for the first successful same continent RaDAR to RaDAR QSO.

Five (5) points for the first intercontinental (DX) QSO

Ten (10) points for the first successful inter-continental (DX) RaDAR to RaDAR QSO.

9. Log Sheets

Log sheets must be submitted by 13 April 2019, 20 July 2019 and 16 November 2019 and sent by e-mail to edleighton@gmail.com Note: A photo of the station should accompany every log entry including each new location that moveable RaDAR stations visit. The results and photos are used to promote RaDAR and amateur radio.