This is A Page Dedicated To The GB7IV D-Star Project
GB7IV D-Star Has Been Shelved & We Continued Our
Work Towards Progressing With C4FM On Site
You Can Read The History Of The Project Here In Our Archive


Band: 2M (RV62)

Output:145.7750 MHz
Input: 145.1750 MHz

This is a DIGITAL VOICE repeater.
(NOT licensed for ANALOGUE Voice repeat)

This DV is for D-STAR capability

11.8dBW 14.791 Watts ERP

January 2019
This is the GB7IV rack with IV in it, with the AC & DC shut down switches, the gap is for GB3 SU and its duplexers, on the rear panel in that gap can be seen the dual band repeater combiner.
Its not cabled up yet as its not yet needed! CLICK IMAGE

Antenna picturer of the IV aerial located SMC Chandlers Ford

Its a triband Colinear for 2m 6m & 70cm aerial height ASL: circa 60ft AGL

Also you can see on the pole: 40m & 80m Meter trap Dipole, and modified Log Periodic TV Aerial for FM band listening, doing long term weather survival tests.

GB 7 IV is a 2 Meter D-Star Repeater operating on 145.775MHz, previously in Chandlers Ford, Eastleigh, Hampshire.

GB 7 IV is funded by Ebay sales and donations from its users, The RF engineering work is undertaken by SHRG members, while The D-Star lad's concern themselves with the Internet side of things.

recently located at SMC, which is in an RF hole to the West of Eastleigh in Central Hampshire, it has not yet achieved interconnection with the rest of the world, and is thus is still a stand-alone D-star unit, Our Lad's have been working on the hardware, and software to achieve this aim, which included scrounging a suitable computer, and running Suitable software, and arranging connection to the Internet.

GB7 IV uses :
D Star repeater ID RP200V ERP of around 20Watts from the aerial

controller ID RP2C

Computer :

Running operating system :

PSU SMC FP 15 ( badged Yaesu unit )

Duplexers Wavecomm on loan from GB 3 SH

Rack generic 19"

Feeder RG 213

Mast 2" thickwall 20ft Aluminum mast

Aerial 6, 2 & 70cm Triband colinear

Battery back up not yet fitted


NEWS 2021
It is hoped that now we have duplexers and filters almost ready to go with this repeater. Sorry for the delays but as soon as its safe regarding Covid 19 we hope to get back on site and move forward with this repeater.

We are in the process of getting GB 7 IV moved to the Thornhill area of Southampton, this will give much improved coverage for base stations, mobiles and hand held stations, as this is a commercial site we will change over to a commercial grade monoband Marine White Fiberglass aerial from Procom: CXL 2 -1LW/l, this ground plane-less aerial, is just 1110mm long with 0dbd gain, and has a high wind speed specification and survival.


In preparation of Moving GB7 IV, work is progressing on its rack, the monitoring equipment, together with progressing its connection to the world wide D Star network.

The Cat 5 Cable has been pulled through, and connected to the computer which has been programmed up with the Centros operating system, we now await work at SMC to allow traffic, then it will be down to the D star lads to make the final connection to the D star network.

A back up 32AH battery has been fitted to get GB 7 IV over browns out and short black outs which are fairly common in
Chandlers Ford.

However the Computer, which is needed for Linking, will only have an UPS to power it down in the event of a 20 minute or longer power cut.

The D Star Icom Repeater surprisingly lacks any Meters or LEDS to tell us what its doing, so a 19" 3U rack unit has been built with the purpose of monitoring PSU / Battery Volts and Current drawn, thus showing its is receiving / idle or transmitting!

Monitoring of battery charge current and voltage, the photos show the Voltage Monitoring Fitted, however we await the Battery monitoring meter, which is on its way from China, as its 1/3 of the price of UK supplied models!


Prediction mobile coverage from new site
Thornhill early in 2017

The map below is from RSGB Repeater
Site from its QTH Chandlers Ford

work in progress the shinny 3 U front will be fitted with meters to the inverted shelf section above it..

The famous Chandlers Ford crows like the aerials too

Battery lurking rear of rack,
note fuses on both 13V & 0V cables

Monitoring of battery charge current and voltage, the photos show the Voltage Monitoring Fitted, however we await the Battery monitoring meter, which is on its way.

Sunrise from GB7IV in timelapse video 18 10/17 CLICK HERE Video From David Barrett Filmed 20ft below the aerial

GB 3 SH Duplexers on loan