Mid Sussex Repeater Group

GB3HY is a 70cm amateur repeater located at Hayward’s Heath, West Sussex, operating on channel RB5 (RU250).  The unit provides excellent coverage of the central Mid-Sussex weald area, radiating from a 6dB gain omni-directional four-stack dipole aerial.

First commissioned in June 1989, the repeater has undergone a series of upgrades and modifications to bring it to its present-day condition.

History:                         First operational using Pye 460 series units
                                     Upgraded in October 1992 to Motorola MICOR units
                                     Recently upgraded to Tait T800 series units

Location:                       Princess Royal Hospital       QTHR: IO90WX
                                      Old Water Tower                   NGR: TQ339231
                                      Hayward’s Heath                  Latitude: 50.99173144°N, Longitude: 0.093448086°W
                                      West Sussex

Channel Frequencies: Transmitter output 433.125MHz     Receiver input 434.725MHz

Current Equipment:      RF rack comprising Tait T800 series units
                                     Single-aerial working
                                     Motorola four-cavity band pass-and-notch duplexer
                                     Logic based on 87C51 micro-controller designed and built by Paul, G0OJA
                                     Battery backup using two 12V 92Ahr batteries now operational
                                     Implementation of remote control and status-monitoring system in progress

Operating Parameters:    25W ERP
                                        25kHz channel spacing, 12.5kHz being considered
                                        Access by CTCSS only on 88.5Hz (code E)
                                        Time out period 5 minutes
                                        Call-sign and location text sent every 15 minutes when in beacon mode
                                        Call-sign text only sent every 15 minutes when in repeater mode
                                        End-of-over indicator text K, planned to be B when operating on battery backup

Organisation:                  Funded solely by donations from users
                                        Donations are welcome; please contact Gordon, G3XTH, g3xth@msars.org.uk

Engineering Team:        Repeater Keeper:                 Gordon, G3XTH
                                       Engineering Support:            Paul, G0OJA
                                                                                     Alan, G8YKV
                                                                                     Phil, M5BTB

(click any of the images for a larger version)

Coverage Map

Old Water Tower at Princes Royal Hospital

Pre testing of new Tait Hardware

Side View with some members of the installation team

 Phil M5BTB and Gordon G3XTH

Rear view showing duplexer

Front view with doors and blanking panels removed

Front upper view

showing front of Tait hardware and main, test and reserve feeders

Front lower view

showing front of Tait hardware and location for backup batteries

Side view

showing duplexer, pre-amplifier and Tait hardware shelf rack

Rear view

showing Tait hardware shelf rack and RF cabling

Lower view showing

Charger for backup batteries, DC/DC inverter and electricity consumption meter

Backup Batteries, after instalation, with protective covers removed

Cabinet cover, added to prevent water ingress

Page last updated 16/04/2010