GrahamH's photos with the keyword: link

Satellite dishes for networked paging at a site previously operated by me. The hut was built by my former business and the tower and equipment box were provided by an earlier operator. Bald Hill, Tamworth. Terminated dream.

A two page test report for the transmission links for a two-way radio system. The links joined the track-side base stations and the control centre. The system is no longer in use. This is used for checking the links shown here: www.ipernity.com/doc/grahamh/24117033 E&M signalling over copper pairs in Australia was done using the 4W (1 pair each direction for the audio signal) circuit, ie no additional conductors. This is done in a similar manner to that used in feeding DC power to a condenser/electret microphone in a public address or studio sound system. The direct current for the signalling flows one way equally on both wires of a pair with the earth being used as the return conductor.

A two page test report for the transmission links for a two-way radio system. The links joined the track-side base stations and the control centre. The system is no longer in use. This is used for checking the links shown here: www.ipernity.com/doc/grahamh/24117033

General overview of the terrestrial side of the Train Radio system as built. This shows whether the radio base site was greenfield (1), used an existing building with a new mast (2) or used an existing radiocomms site (3). The type of linking, usually via a node, to the relevant train control location. View using this link to read details. www.ipernity.com/doc/grahamh/24117033/sizes/2048 See some of the sites using this link. www.ipernity.com/doc/grahamh/album/466749?with=24117033 or search using the Ipernity search box for 'countrynet'

General overview of the terrestrial side of the Train Radio system as built. This shows whether the radio base site was greenfield (1), used an existing building with a new mast (2) or used an existing radiocomms site (3). The type of linking, usually via a node, to the relevant train control location. View using this link to read details. www.ipernity.com/doc/grahamh/24117083/sizes/2048 See some of the sites using this link. www.ipernity.com/doc/grahamh/album/466749?with=24117033

A test sheet used to record basic measurements on a 4 wire plus E & M circuit. For this project the functionality was mostly derived from either two pairs of copper wires or a 64K slot from a 2M PDH stream. The links connected train radio base station controllers with the central control for the railway route. See www.ipernity.com/doc/grahamh/24117033/in/group/873405

Hard to return now. The address of the radio comms installation depot of my former employer, PMG/Telecom Australia. The old single story brick and corrugated asbestos sheet roofed factory/warehouse building is gone, see note.

Simoco (prev Philips) rack with Exicom link radio in the Gresham Train Radio hut. April 1994.

Who ya gonna call. A trafelite label. Excess to requirements. An order wire is a communication system for technicians which is available at many locations along a transmission route. It is similar to a party line telephone. This enables techs to co-ordinate maintenance and fault-finding. See note.