Category Archives: Ham Radio

144 MHz 1.25 kW Amplifier

Over the weekend I worked on my 1.25 kW solid state PA based on F1JRD’s design from Dubus using a MRFE6VP61K25H. I bought a complete kit at the Friedrichshafen Hamfest 2012 from F1JRD and F5CYS and built it up late 2013 but due to problems, I never had more than around 40W output. This weekend, with a new set of capacitors from ATC I rebuilt the output matching and fired it up once again. With my 1kW/50V power-supply I can get around 600W output, which his more than enough. This is still a work in progress, but things are moving forward with the project.

CQWW SSB 2013

This map shows some of the stations worked during CQWW SSB Contest, 26-27 October 2013. Operations using M0STO’s tri-band 4-ele Yagi and 300W from the Kelvedon Hatch Secret Nuclear Bunker (GB0SNB) operating as G3XBF.

We set out with the aim to work as many DXCC entries as we could within the 24 hours we were able to operate. Operations started at 16:40 UTC on the Saturday an finished at 15:10 UTC on the Sunday; operating most of the night. 54 DXCC entries worked.

The location details are from QRZ.com, where possible.

Map

Click the map once for image details, and again for high resolution image.

Photos

Here are a few pictures from the 2013 CQWW contest, taken by Peter Allen, G0IAP.

Pictures from CQWW 2013

M0STO setting up the EME SCAM 12 on the top field
Pictures from CQWW 2013

Moving the SCAM 12 to a lower field because of high winds
Pictures from CQWW 2013

M0YOL guiding M0STO in moving the beam in his car
Pictures from CQWW 2013

Erecting the HF beam on another SCAM 12
Pictures from CQWW 2013

G7UVW and M0STO tuning the beam & checking the SWR
Pictures from CQWW 2013

G7UVW and M0STO reflecting on the erection of HF beam and VHF EME beams (background)
Pictures from CQWW 2013

Inside the lockup at GB0SNB
Pictures from CQWW 2013

Tuning the linear up
Pictures from CQWW 2013

2m Yagi looking a bit bent, on the Az/Ele rotator for EME
Pictures from CQWW 2013

Both beams as coax is run into lockup
Pictures from CQWW 2013

G7UVW operating and logging
Pictures from CQWW 2013

M1GEO swinging the beam as G7UVW is operating
Pictures from CQWW 2013

G7UVW logging as M1GEO operates
Pictures from CQWW 2013

G7UVW drinking tea as M1GEO operates
Pictures from CQWW 2013

M0STO setting up EME equipment
Pictures from CQWW 2013

M0STO configuring HRD to track the moon
Pictures from CQWW 2013

M0STO deep in the settings!
Pictures from CQWW 2013

G7UVW and M1GEO tidying their “private” log, collecting their own DXCCs!

Marconi Centre & Lizard Wireless Station

During a family visit to Cornwall in July 2011, I had the opportunity to visit the Lizard Wireless Centre at Lizard, Cornwall and the Marconi Centre at Poldhu, Cornwall. This page just has a few pictures that I thought may be of interest. If you click the pictures, more details will appear about the image; clicking the image again will show the full resolution image. If you would like an image without the copyright notice, contact me – it’s not a problem!

The Lizard Wireless Centre

The first Coastal Path sign mentioning the Lizard Wireless Station.

Commemorative plaque outside the Lizard Wireless Station.

National Trust sign, also outside the wireless site.

View across the bay from the station.

The station (2 huts on left) and lighthouse site (right).

Final part of the footpath leading to the station.

Also near buy, the Lloyds Signal Station, used by Lloyds Insurance to keep track of ships.

The open sign and view out to see.

The (original) workshops as used by Marconi. Antennas located out of shot to right.

Inside the workshop, the Marconi station. Some parts are replicas, some original.

The Wireless Station’s QSL Card for their Amateur Radio Station, GB2LD.

The view from the workshop window.

My car, parked where sections of the World-War 2 Chain Home Radar were sited.

The Marconi Centre (Poldhu)

The start of the footpath leading to the Marconi Centre.

The outside of the Marconi Centre.

Sign explaining the view of the radio field.

Foundations of transmitter house, used for first Atlantic communications by Marconi (designed by A. Flemming).

One of the Marconi Centre’s modern Amateur Radio Stations (available for use by Radio Hams).

Chris, G8OCV works PSK31 from the Marconi Centre

A Morse key produced by Marconi’s Wireless Telegraphy Company Ltd.

Monument to Marconi standing in the old antenna field outside the Marconi Centre.

These images show the 4 plaques on the sides of the monument. Click an image to enlarge.

 

Click an image to enlarge