Category Archives: Field Day

RSGB 21/28 MHz contest

The RSGB contest provided an ideal opportunity to focus activity on the higher HF bands. Previous John M0UKD and I had built beams for 28 MHz 3e beam and 21 MHz 4e beam using the design on DK7ZB website. 28 MHz is a compact design using a 3m boom, and 21 MHz is somewhat bigger at 5m boom.

The Racal PU12 mast was used for the 28 MHz antenna and Clark 10 for the 21 MHz antenna. Power was provided by the Honda 2KW silent generator and the radio was provided by George M1GEO the Icom 7700 delivering 200w RF.

The operating was alfresco as the October weather was sunny and warm. The shack table was positioned close to the mast ready for armstrong rotation The Clark mast was modelling some new blue legs, recently fabricated by Brian 2E0FHU. They worked perfectly and once assembled they provided a sturdy base.

A quick check with the MFJ analyser confirmed the antenna was spot on resonance, and so the CQ calling could commence.

Despite a valiant effort on both 21 and 28 MHz conditions did not support the number of QSO we had hopped, in fact you could say it was a challenge to work anyone at times. QSO could be hard to tease out, and we decided the best method was to work anyone we could hear. Some big DX did arrive, as we managed to work ZS6AI, ZS5DCF, CX8DS, VP8NO and PS8BR to name a few. The bands did seem to be open, at one stage we listened to a CW beacon in South America that was very loud (apparently 10w).

Despite the lack of activity or poor band conditions we enjoyed our time operating outdoors in the sunshine.

Both homebrew beams worked well, and this may well be the last time we operate outdoors in 2015.

Further picture from the day are available online.

Thanks to everyone we worked 73 Dave M0TAZ, George M1GEO and John M0UKD

EDIT (30 November 2015)

The RSGB results come through today, and we were pleased to have won the Powditch Trophy for the Leading UK Multi-Op station achieving the highest score on 28MHz. With the help of the team, M0TAZ M0UKD and G3SVK (G8OCV in support).

RSGB 2nd 70MHz Contest

We had some great September weather today for the 2nd 70MHz contest. We setup a station at the Kelvedon Hatch ‘Secret Nuclear Bunker’ as seen above, using a new 70MHz amplifier and a 4 element DK7ZB 12.5Ω Yagi as M0UKD/P.

QSO Map – 2nd 70MHz RSGB Contest

Conditions seemed quite normal, we worked no Scotland or Ireland but our best DX (as many others) was PA4VHF at 449km. Other highlights were GJ3YHU in Jersey and M1CJN/P in the North York Moors.

A very enjoyable day of operating and testing the new amplifier. Next week, it’s the Practical Wireless 70MHz contest, so lets hope for the same weather and some band openings perhaps? Maybe thats asking too much 🙂

The Claimed Scores are available. Thanks to Dave M0TAZ, George M1GEO, Dave M0YOL and Chris G8OCV for help & company! 73 de M0UKD – John.

RSGB 2nd 70MHz Contest at Kelvedon Hatch

Meteor Scatter Experiments

This weekend was very close to the peak meteor shower from Perseid. This gave us an ideal opportunity to try meteor scatter for the very first time, using a 9-element G0KSC antenna at 10m and 100w amplifier. The antenna had G7UVW‘s LNA adding a further 20dB of gain to the receive path at the mast-head.

Using WSJT we were able to decode a number of stations, although it took some reading, and trial and error to make our first QSO. The first QSO was with OK1UGA in JO80dd, some 1137 km. Through the course of the evening we completed the following QSO.

Callsign	QRA Locator	Distance (km)	Freq (MHz)	Mode
OK1UGA	JO80dd	1137	144	FSK441
DF5NK	JN59PM	812	144	FSK441
SP2FRY	JO83WR	1215	144	FSK441
S56P	JN76PO	1225	144	FSK441
OK1DQT	JO70IB	1027	144	FSK441
YU7TT	KN05FW	1662	144	FSK441
M1BXF	JO02FE	71	144	JT6M
F8DYR	JN07WL	487	144	JT65A
I6BQI	JN72AK	1456	144	FSK441
SM7FWZ	JO78MM	1134	144	FSK441
IZ3WQO	JN65CL	1110	144	FSK441

Since the use of WSJT is not much of a spectator sport, we also had a 20 metre beam up to shout on HF, which was later changed to 17 metres to avoid the ongoing CW contest. Full log breakdown here. Best DX was CE6SAX (12320 km) and YB3HJM (12280 km).

In the afternoon, John M0UKD arrived with a homebrew 4 metre beam which he built on the Saturday (8th Aug 15) to a DK7ZB design.

We worked 40 stations in 2 hours, which I think is good for 70MHz. Our best DX was PA4VHF at 449km.

RSGB IOTA Contest

This weekend saw an activation by the contest group for the RSGB IOTA Contest. Members used the club callsign for the weekend event.

The Saturday was a good day, with a visit from RSGB Regional Rep Steve M1ACB, who declared our burgers and BBQ to be of suitable standard.

However, on the Sunday, following a day of heavy rain, the field was flooded and members were keen to head home for a rest!

Below, a map of the QSOs made. A full breakdown of the log can be seen here, for those interested. 476 QSOs were made as part of a casual entry.

Operation Bunker

Members of the contest group were invited to attend ‘Operation Bunker’: a military vehicle, memorabilia and re-enactment weekend attended by vintage military personnel from all over the South East. Of course, we obliged.

We operated the bunker special call GB0SNB from beside the main mast, using SSB, CW and Data modes. In total we contacted 368 stations in 47 countries around the world. Our furthest contact (best DX) was into Chile at 11,330 KM on 14 MHz digital modes. An interesting selection of contacts were made, including Japan and south Americas. Unfortunately no Oceanic stations.

You can take a look at the log (and other statistics) by clicking here. Some images from the weekend are available below, taken by Peter, G0IAP:

CQWW SSB 2014

The club took part in this years CQ World Wide contest this year from the Secret Nuclear Bunker. The event was organised mainly by George, M1GEO and Dave M0TAZ. We operated two stations, one on 20m with George’s monoband 3 element Yagi and one on 15m with Dave’s 2 element Quad. We also operated on some other bands with a doublet.

The total stations we worked was 1743. George M1GEO has compiled some very interesting statistics which are well worth a browse. Take a look at them. The full log can be viewed as a 35 page PDF file. Some photos can be seen in the gallery. More will be added as they come in! There is also a QSO Map.

We worked 109 countries in many CQ zones, 33 out of 40 were worked. It was a great event and one I’m sure one we will add to the calendar for 2015!

Below is a world map of the contacts that were made over the weekend. Click the image to view full size!

Activity Day

On Sunday 5th October 2014 a few of us got together at the bunker for a bit of casual operating. Several overlapping contests (Oceanic DX and RSGB 21/28 MHz) had lead to some activity on the higher bands, so we decided to see what was around, just collecting some DX. The standard invite went out to the local clubs and to usual individuals by text message. Dave M0YOL, Chris G8OCV and George M1GEO formed the core of the ops, but given it was short notice we didn’t expect hoards.

Conditions on the lower bands seemed poor, with 40 meters being a real struggle to keep regular QSOs. The IC7000 auto-caller was greatly appreciated. We set up station inside the back of my car, since this gives some shelter from the wind (and generator noise) as well as the boot hood protecting from rain (we didn’t need it). The picture below shows the setup, as well as the reflection of the mast in the laptop screen (and M1GEO).

During operation, we noticed that the antenna wasn’t performing as well as usual, and so we set off to investigate the problem. We found a break in the home-brew 3-inch ladder line which runs from the balun on the compound wall to the centre at the top of the mast. However, in the process of finding the problem, the amp had been powered into the unloaded balun and so the balun had become very hot dissipating the power from the amplifier – this in turn had melted the insulation on some wire (homebrew with plastic insulation and not PTFE or Teflon), and some shorts had arisen. Fortunately we had a connector block and a spare balun in the kit box, so were able to quickly address the problems. The QRO balun will be reinstalled once rebuilt (Chris G8OCV has ordered PTFE/Teflon wire at 12AWG, so 2.4mm diameter, 88A rated).

All in all, around 40 QSOs were made.

PW 4 metre Field Day

Dave M0TAZ expressed an interest in early September to take part in the 70 MHz Practical Wireless contest on the 28th of September. A few emails here and there to rally the troops and come the 28th we had a ready gang of radio amateurs.

By the time George M1GEO and Chris G8OCV arrived, Arentas 2E0WUF, Peter G0IAP and Dave M0TAZ were in the process of setting up.

Here, Dave M0TAZ operates the 4 metres station using his homebrew 6 element Yagi and Icom IC7100.

While Dave M0TAZ was operating on 70 MHz, George M1GEO, Chris G8OCV and Peter G0IAP did some operating on 40 metres, and worked 81 stations during the operation on Sunday afternoon. The station was pretty al fresco, with the radio stacked on some boxes and the operators chair being an old toolbox.

HF SSB & 144 MHz Trophy

This weekend Dave M0TAZ took part in the 144 MHz trophy contest as well as a few HF stations in the RSGB HF SSB Field day from the Bunker site. He kindly provided this report.

The contest attracts activity from all over Europe, and on Sunday it also coincides with the low power back packer series. The contest has a number of categories from 24 hours to 6 hours. Dave M0TAZ decided to opt for a casual entry on Saturday only, operating for just under 4 Hrs. The contest was very busy, with a lot of high power multi-antenna UK stations with exceptional signals.

Using a Icom IC-7100 with 50w and a 12m mast supporting a 9-element tonna, Dave was able to work 41 stations.

Some DX highlights for the day was

DL0GTH in JN50 @741 KM.
DA0FF in JN40 @ 688 KM
DL0GM in JO31 @520 KM

You can view the claimed scores here: http://www.rsgbcc.org/cgi-bin/claim.pl?Contest=144MHz%20Trophy&year=2014

On Sunday, Dave decided to work a few HF stations, the RSGB SSB Field day continued
until 2PM local, so set up a simple station using 100w from the Icom into a doublet antenna 20m per leg fed with 300 Ohm ribbon cable.

With the able assistance of Fred G3SVK we worked 35 stations quickly before getting sidetracked by some JA stations calling on 21 MHz.

After a few calls I was able to work:

JA7NVF
JA1OGI
JM1PLN

I also operated on 5 MHz and was able to work Mal G3KEV/p in Scarborough and Peter G4LNA in Hertfordshire.

A map showing the QSO completed on 144 MHz is available here: https://maps.google.com/maps?q=http://www.rsgbcc.org/vhf/kml_files/2014/ONatUP7C7ck9GURxR8dAElXIfGezADV

Dave M0TAZ

Work The World

This weekend sees activation of GB0SNB for the contest group’s Work the World Weekend. A chance for members to operate outside of a contest and to experiment with equipment in a less intensive style field day.

The weekend started off in a very informal manor, with Chris G8OCV relaxing in the sunshine whilst waiting for other members to arrive. At 8:30am, the WX was good and the sun warm!

The day progressed well, with Tony M0HQE and Chris G8OCV assembling the 3 element Yagi on 17 metres.

Attention then turned to erecting Dave M0TAZ‘s 2 element Quad. Here, we see Tony M0HQE and Alan G3RJI in the foreground with Graham M0PAX and Dave M0TAZ in the background.

Taken just as the sun was setting, the two large antennas can be seen with the club caravan and members vehicles. The black dot suspended above the caravan is part of the 40 metre dipole configured as an inverted-V.

Here you can see the 17 metre station, consisting of an Icom IC7700 with logging laptop, tea mugs, paddle and microphone all cosily settled inside the club tent.

Meanwhile, Dave M0TAZ operates with relative comfort inside the club caravan. He’s using a Kenwood TS590s on 40 metres with the dipole, managing the massive pileup. He was alternating between 20 metres and 40 metres, SSB and data modes.

In total, we made just shy of 1000 QSOs during the weekend. The total was 973. Not bad going at all, and I think the RSGB Bureau will be busy! The breakdown goes something like this:

Band	SSB	CW	RTTY	PSK	Totals
40 metres	120	0	0	0	120
20 metres	138	221	36	39	434
17 metres	72	347	0	0	419
Totals	430	468	36	39	973

It is worth noting here that all of the CW QSOs were made by Fred G3SVK!

During the weekend we managed to work 68 separate DXCC entities, 16 on 40 metres, 47 on on 20 metres, and 41 on 17 metres.

The weekend saw a few firsts for GB0SNB. First QSO with Anguilla (VP2E), Bahrain (A9), India (VU2), China (BY), Mongolia (JT) and Puerto Rico (KP4) to name a few.

GB0SNB/MX0SNB/M0SNB – Kelvedon Hatch Secret Nuclear Bunker

RSGB affiliated amateur radio contest group & special event station in a RGHQ 5.1 Cold War Nuclear Bunker, hidden in the depths of Essex!