Leicestershire Repeater Group
Providing a service for all radio amateurs
Welcome
Recent Blog Entries
by Peter G8DKC | 0 comments
by leicestershirerepeatergroup | 0 comments
by leicestershirerepeatergroup | 0 comments
by Peter G8DKC | 0 comments
Repeaters and Beacons
Located in Charnwood Forest, Leicester. This shows the details of site equipment. We shall be pleased to receive any repeater or beacon reception reports and these can be submitted by telephone, post, email or via the web.
GB3GV
TV repeater
FM Tx and Rx: Transmit: 1318.5MHz, Receive: 1249MHz.
Antenna: Alford slot on Tx and Rx.
Continuous operation with test cards, work in progress to improve Rx sensitivity and power efficiency.
Beacons
The 2.3, 3.4 and 10 GHz beacons are co-sited, 220metres ASL, at Markfield about 8kms north west of Leicester; locator reference IO92IQ,.
In 1981 the 10.400GHz, WBFM, beacon GB3LEX became operational and in 1985 was joined by GB3LES on 2320.955MHz.
Technical details:
GB3LES
In 1981 the 10.400GHz, WBFM, beacon GB3LEX became operational and in 1985 was joined by GB3LES on 2320.955MHz.
Technical details:
GB3LES
This is a 2watt transmitter, F2 modulated with callsign and QRA locator; ZM24J.
The NBFM transmitter comprises a 0.5watt Wood & Douglas source on 386.826 MHz which is filtered and then amplified to an output of approximately 10watts. A retuned Microwave Modules 1296 Varactor multiplier is then used to triple the input and after filtering drives a varactor doubler. The doubler, which is a VHF Comms design by DF7QF, produces, after further filtering, a final output power of approximately 2watts. A 25m length of FHJ50-2 coaxial cable is used to feed the RF to the antenna which is an Alford slot, the performance details of which may found in the Microwave Handbook chapters 14.29, 15.26. The antenna is contained in a 'radome' fashioned from 50mm diameter of gray plastic drainpipe. The transmitter and keyer were built by G4LRT. The Alford slot was built by G3JVL and G3WDG.
GB3LEX
Originally commissioned in 1981 the transmitter comprised a 200mWatt waveguide cavity Gunn oscillator, tuned to 10400MHz. WBFM modulation was applied via an offset varactor diode mounted in the waveguide cavity.
The beacon antenna is 16 slots in one face of a length of full height WG16 (UR90). The slots are equally distributed about the centre line of the broad wall. When the beacon was re-commissioned, following the collapse of the mast with loss of the waveguide feeder, it was updated to be a NBFM transmitter on 10368.955 MHz. The original waveguide slot antenna was re-used and this gives an ERP of 1W with a -3dB beamwidth of ± 90deg on a heading of 180 degrees.
GB3LEF
The transmitter comprises a 94 MHz source which is amplified and frequency multiplied to produce a filtered output at 3400.955MHz of 1.5Watts. The transmitter has been rebuilt, by G4LRT, using much of the hardware recovered from the Sheffield beacon, GB3UOS.
The antenna is a Alford slot in a plastic drainpipe radome.
Last updated: 4 July 2011
The NBFM transmitter comprises a 0.5watt Wood & Douglas source on 386.826 MHz which is filtered and then amplified to an output of approximately 10watts. A retuned Microwave Modules 1296 Varactor multiplier is then used to triple the input and after filtering drives a varactor doubler. The doubler, which is a VHF Comms design by DF7QF, produces, after further filtering, a final output power of approximately 2watts. A 25m length of FHJ50-2 coaxial cable is used to feed the RF to the antenna which is an Alford slot, the performance details of which may found in the Microwave Handbook chapters 14.29, 15.26. The antenna is contained in a 'radome' fashioned from 50mm diameter of gray plastic drainpipe. The transmitter and keyer were built by G4LRT. The Alford slot was built by G3JVL and G3WDG.
GB3LEX
Originally commissioned in 1981 the transmitter comprised a 200mWatt waveguide cavity Gunn oscillator, tuned to 10400MHz. WBFM modulation was applied via an offset varactor diode mounted in the waveguide cavity.
The beacon antenna is 16 slots in one face of a length of full height WG16 (UR90). The slots are equally distributed about the centre line of the broad wall. When the beacon was re-commissioned, following the collapse of the mast with loss of the waveguide feeder, it was updated to be a NBFM transmitter on 10368.955 MHz. The original waveguide slot antenna was re-used and this gives an ERP of 1W with a -3dB beamwidth of ± 90deg on a heading of 180 degrees.
GB3LEF
The transmitter comprises a 94 MHz source which is amplified and frequency multiplied to produce a filtered output at 3400.955MHz of 1.5Watts. The transmitter has been rebuilt, by G4LRT, using much of the hardware recovered from the Sheffield beacon, GB3UOS.
The antenna is a Alford slot in a plastic drainpipe radome.
Last updated: 4 July 2011