Site Records

SiteName: Rugby Radio Station

OS Grid Ref: ('C' Building) SP553747

Sub Brit site visit 28th May 2003

[Source: Andrew Emmerson]

Sub Brit visit to Rugby Radio Station, 28th May 2003
Sunny weather again favoured this visit to BT's Rugby Radio Station in Middle England on Wednesday 28th May. It was the western half of the site that we visited; the 1953 HF transmitter house and office complex is on the other side of the road.

Photo:The VLF Transmitter Building (C) at the top of the picture with the generator hall at the bottom
Photo from Rugby Radio Museum

Our purpose was to see the 'C Building' transmitter hall of the original Rugby radio station that was erected in 1926. One of its first links was the transatlantic telephone connection to the USA, replaced after the first underwater telephone cable (TAT1) was opened in 1956. Until 31st March Rugby operated a 16kHz VLF transmitter (callsign GBR) for transmitting to submarines as at Criggion but this is now out of use.

The sole remaining task of Rugby radio station is transmitting the time signal (callsign MSF) used by the radio-controlled clocks you buy at Argos, Maplin Electronics and elsewhere and this will continue until BT's contract expires in 2007. In the near future all the antenna towers will be demolished except the two holding the 'T' antenna of MSF.

Photo:The tuning coil and the coarse variometer (left)
Photo by Nick Catford

Our tour first visited the coil room on the upper floor of the transmitter hall. The vast arrays of copper 'plumbing' were similar to those of Criggion but in the larger building looked more impressive. All of this was supported on wooden framing held together with plastic bolts (no ironwork allowed that might detune the radio performance). The apparatus was built to carry 1000 amps of radio-frequency current, although it normally operated at 750 amps. The frequency transmitted was 16kHz normally, although tests had also been made at 22kHz. The transmitter valves operated with an anode voltage of 12 kilovolts, supplied by some pretty powerful power transformers or else by standby generators that we saw later in the power hall. Transmissions were normally MSK (Minimum Shift Keying, a form of FSK-Frequency Shift Keying-used to carry digital information on a radio carrier) and occasionally A1 (on-off keying or 'OOK').

Photo:The transmitter hall
Photo by Nick Catford

The architecture of the transmitter hall was a restrained neo-Georgian favoured by the Board of Works and we noted what appeared to be some artistic stained glass in the windows. In fact it was blue and purple plastic to filter the colour of sunlight that might otherwise trigger the fire alarms (the place suffered a disastrous fire in 1943, not due to enemy action).

We then went downstairs to see the transmitter room. Much of this was very 1960s in appearance, with polished grey metalwork, bronze control panels and engraved Perspex signs. The spare valves are kept in a teak and glass display case, looking just like a museum! All the old valve monster transmitters are now disconnected, with just around the corner the modern solid-state Telefunken MSF transmitter and an older standby unit for MSF.

The old MSF (C2) Transmitter

The Museum

Then to the power hall and its gallery, where the staff have assembled a very worthy museum (which it is hoped will find a new home shortly).

Close to and surrounding the transmitter hall are several elderly and fairly stout telegraph poles with long arms and many insulators and wires. The arrays are striking as they look incredibly neat and tidy to the trained eye. In fact these are all connected to earth and form an 'earth mat' to improve the radio performance of the transmitter.

20 yards to the south of the generator hall are the buried fuel tanks for the generators. They consist of into two bunded concrete lined rooms linked by a door between; each room is big enough to house a couple of squash-courts. There are four massive oil tanks, two in each room. The tanks are semi-sunken with three metres below ground and three metres above which is covered with soil and grassed.

We had a walk to one of the towers and a quick photography session. In the distance was the 1930s-built HF (short wave) building, now disused, and nearby two wartime Nissen huts still used to house stores. And that was it.

This visit was a private trip arranged by a Sub Brit member, with numbers strictly limited by our host. Many thanks are due to the BT staff, who showed us round and answered our questions with great patience.


Eight of the twelve 820' masts at Rugby were due to be demolished during the evening of of 19th June 2004. For the full story and pictures click HERE


Articles in the Post Office Electrical Engineers' Journal and Radio Bygones
Creighton, J.L. The New Very-Low-Frequency Transmitter at Rugby Radio Station. POEEJ January 1969 (Vol. 61), p.232

Gracie, J.A. Rugby Radio Station. POEEJ April 1939 (Vol. 32) p.16

Faulkner, Brian. Rugby Radio Station. Radio Bygones , April May 2002, pp 14-20 (substantial article on the station's history).

'Something in the air - a guide to the Ruby Radio Masts' by Pete Chambers (for further details including how to obtain a copy click here.


Connected Earth web site
A history of Rugby Radio - excellent technical history

All archive photographs are © Rugby Radio Museum and are reproduced with permission

Andrew Emmerson
Bob Jenner
Steve Pell

Nick Catford
Rugby Radio Museum

For further photographs of Rugby Radio Station click here

[Source: Andrew Emmerson]

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