Category Archives: Event

RSGB AFS Phone Contest

On Saturday 16th January George M1GEO, Chris G8OCV and Dave M0TAZ took part in the RSGB AFS phone contest. The idea was to give the Secret Nuclear Bunker Contest Groups first outing of the clubs call MX0SNB. The clubs contest site benefits from having a large doublet antenna (40m per leg) 30m up on the large onsite mast.

Using the Icom 7100 and 100w we noticed quickly while it was possible to match the antenna it didn’t seem to be working very effectively. The shack is located 20m below ground, in the original Home Office radio room. Once inside the bunker you have no idea what may have occurred. We decided to go back up to the mast and check, and on taking the doublet down we discovered one of the 300 Ohm feeder legs had become detached.

The antenna is located close to 30m above the ground, and the mast is already very well elevated, making it sometimes hard to maintain a working HF antenna in the winter weather. A quick fix later and we was soon back on the air.

We operated from 3 till 5 PM and managed to work over 100 stations. The contest was well supported with many club stations and members from around the country. It was just a casual entry, but enabled us to get our club call on the air. Thanks to everyone we worked. 73 MX0SNB

50/70/144/432MHz Christmas Cumulatives

The RSGB 50/70/144/432MHz Christmas Cumulatives Contest series run from the 26th to the 29th of December each year and are intended as a bit of fun in the contester’s calendar. The contest exchange is the usual RS(T), Serial Number and 6 character locator (e.g. JO01DQ). These contests are really easy to become involved in, and often provide a good excuse to escape the house after Christmas.

This year, Dave M0TAZ, Dave M0YOL and George M1GEO decided to operate alfresco from the Bunker for the final two days (George having put in token entries on the 26th and 27th for 144 MHz from Home). We operated on 50 MHz, 70 MHz and 144 MHz for the full 2 hours on a picnic table, in large overcoats on cold winter afternoons, packing up in the dark!

144 MHz was to be our main band. For that we used an Icom IC7100 transceiver, DG-8 masthead-preamplifier (GM3SEK design/M1GEO construction), and 9-element tonna (10m AGL), powered from a large 60 Ah sealed lead acid battery.

50 MHz and 70 MHz were run as a sub station. Again, using an Icom IC7100 transceiver and an InnovAntennas 6-element dual band (50/70MHz) yagi (7m AGL), with an 85 Ah leisure battery. The battery also provided mains power via a small inverter, which charged the logging laptops.

The table below shows the number of QSOs made per band on each day, as well as the best DX station callsign, locator and distance. In order of fairness, we switched callsigns on the second day, all points awarded to the SNBCG.

Band	Info	28 Dec 2015 (M0TAZ/p)	29 Dec 2015 (M1GEO/p)
144 MHz	# QSOs	30	40
144 MHz	DX	MI0SMK (IO64XL 525km)	GD8EXI (IO74PC 430km)
70 MHz	# QSOs	7	10
70 MHz	DX	G4ASR (IO81MX 226km)	G4YHF (IO92XW 141km)
50 MHz	# QSOs	8	13
50 MHz	DX	GW5NF (IO81KQ 236km)	GD8EXI (IO74PC 430km)

The map below (click to zoom) shows the worked locators for the Contest. Almost all of the DX was worked on 144 MHz. Produced by OpenContest’s EDI Visualiser.

A very enjoyable activation. Even if it was a little cold! Lots more photographs here.

1.8 MHz CC AFS

Last night saw activation for the 160 metre club calls affiliated societies contest. This is a slow and relaxed contest, with an emphasis on beginners (full rules here).

3 members of the group decided to run the contest from the bunker as there is already an antenna suitable for 1.8 MHz on site. We carefully negotiated the car on to the field (in heavy rain), with the wheels slipping everywhere. As some of you may remember, we have had vehicles stuck in the field before, so it was our concern at 8pm at night with the farmer long since resting at home, that we mustn’t become stuck!

The field was boggy, but we managed to get close enough to run a coax to the mast, and set the station up on the car dashboard. Given we didn’t know the state of the antenna, we took a large ATU with enough inductance should it be needed, with the intention of running a long wire if the doublet had failed. The Icom IC7100 was used to provide the maximum 32W for the section of 160m in concern. Power was provided by a Honda EU20i silent generator. We also opted for a small fan-heater to keep the car warm and small table-lamp to provide light. Fortunately the doublet was okay, and we got underway.

Here we see Dave G7UVW operating the IC7100 through a rain-covered window.

Conditions were very down on last year’s event. The band was cursed with environmental noise. It also didn’t help that we had a dodgy piece of feeder coax, which was undiscovered until the last 15 minutes.

Overall, we worked 34 stations, and claimed a score of 564.

CQWW SSB 2015

This weekend saw members of the bunker group activating the site for the CQWW SSB Contest. Operating from the Dave M0YOL’s caravan awning, we set up two stations, one at each end.

We arrived about midday on Friday 23rd October and got setup. Dave M0TAZ was underway with the construction of his 21 MHz beam while George M1GEO and Dave M0YOL were setting up the caravan. Some time later the 14 MHz beam was built and put on the SCAM12.

Then food! Here, we see the pre-contest dinner inside the awning, with (left to right) Dave M0YOL, Dave M0TAZ and Chris G8OCV.

… and breakfast …

Station 1

Icom IC7700 HF transceiver
Heathkit SB200 amplifier
Yaesu GX600RC rotator

Station 2

Kenwood TS990 HF transceiver
HAL 1200 amplifier

Antennas

14 MHz 3 element homebrew yagi
21 MHz 4 element homebrew yagi
1.8/3.5 MHz doublet; 26 metres
28 MHz vertical dipole; 8 metres
7 MHz ground-plane vertical; ground level

The shack was powered by two Honda EU20i 2kW slient generators with phasing harness, delivering a solid 4kW of mains power. We were a bit worried with the heavy rain on Saturday, so we fashioned an umbrella to help protect the electrics!

During the evenings, it got pretty cold. Here, George M1GEO operates with hood up for insulation, while Dave M0TAZ’s amplifier reports 8C inside the shack.

Band conditions were good (and busy), and many QSOs were made over the weekend. At the start of the contest, some of the lower bands became very packed!

Overall, we worked 1434 in our casual operating weekend. You can see the full log here. Some interesting contacts include Tunisia, many Caribbean Islands, China, Ceuta & Melilla, French Guiana, Liechtenstein, African Italy, Japan, Australia and New Zealand. For more information, look at the full countries breakdown!

Band	QSOs
160m	66
80m	137
40m	276
20m	481
15m	348
10m	126
All	1434

A more comprehensive breakdown of QSOs per band can be found here.

Operator	QSOs
M1GEO	740
M0TAZ	551
M0YOL	143
All	1434

Much more analysis and breakdown can be found on the CQWW 2015 SNBCG pages. Analysis by SH5 v.2.39, Dmitriy Gulyaev UA4WLI.

A big thanks to Dave, Dave and Dave (M0YOL, M0TAZ and G7UVW) as well as Chris G8OCV, Pete G0IAP and George M1GEO for making the weekend possible.

Casual Operating in the Shack

This weekend a few of us decided to head down in to the Shack at GB0SNB to do some operating. The HF bands were full of stations in the Worked All Germany and BARTG RTTY contest, as well as JOTA activation stations.

In between working a few on HF, we managed to pull around 20 contacts on 2 metres, and had a nice pileup on 145.400 MHz.

Above Chis G8OCV and Dave M0TAZ operate on HF.

Here we see Dave M0TAZ operating on 145 MHz FM.

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).

Practical Wireless 70 MHz contest

The popular shortwave and ham magazine Practical Wireless runs a 70 MHz contest once a year. The contest attracts a number of entries from all around the country, including one keen team who climb Helvelyn in the Lake District (M0BKQ/P). M0TAZ’s entry didn’t include a 900m accent to the top of a mountain, since we operated from the Kelvedon Hatch Secret Nuclear Bunker. The location is around 130m ASL and affords nice views over the Essex countryside.

The Setup

Honda EU20i 2kW generator
Transceiver Icom IC7100
Mast Racal 12m PU12
Antenna M0UKD homebrew 4E
Linear amp M0UKD 160w homebrew

The activity started at 1pm and finished at 5; activity levels were moderate, with the first 2 hours being the most active. Many portable stations operate 10w or less so the amplifier and 160W did mean we sometimes had to listen very carefully to get a calling station’s details! People often assume that because they can hear you loud and clear, that their signal must also be good. The weather was sunny and this must have helped encourage people to operate portable outdoors.

We managed to work 47 stations: Our best DX was Scotland GM4JR at 454 km, and we were also pleased to work into Wales GC0VPR/P, GW0EIY/P and GW4EVX/P and also the Netherlands PA4VHF.

The QSO map pins indicates the location and number of stations worked.

Screen Shot 2015-09-28 at 11.10.34

Many thanks to John M0UKD for the use of his beam and 70 MHz amplifier, both worked flawlessly and George M1GEO, Dave M0YOL and Chris G8OCV for assistance with the mast and words of encouragement.

While we were busy on 70 MHz, some of the other guys were having a crack at the CQWW RTTY contest, which was also well underway.

Further pictures are available online.

Thanks to everyone who called, and hope to work you again soon.

73 Dave M0TAZ

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).