Terrestrial
Horizon produced a few models of terrestrial installation meters please scroll down for more information and downloads.
HDTM
The HDTM v1.5 and v2 terrestrial meter (v2 shown above) could store up to 31 DTT transmitters and used BNC input connectors, the older v1.5 also had an RF loop through output. These meters featured a serial interface for updates via an RJ45 socket on the side of the meter and came supplied with a custom programming lead (see wiring diagram PDF below). The serial models can use the 7.2V 3300 mAH battery packs that are more widely available however you should check that they are supplied with an adaptor for the smaller battery connector. To update these meters from a modern computer (without a serial interface) it will be necessary to obtain a USB to Serial adaptor, you will still need the original programming lead (joining the cables together). If you are using a USB to Serial adaptor you will need to configure it as COM1, 2 , 3 or 4. Both the v1.5 and v2.0 are DVB-T only models.
HDTM USB Plus
The HDTM USB PLUS featured and extensive transmitter memory and a UK post code look up function to list near by transmitters. Spectrum and constellation modes were available along with logging functions. This meter was DVB-T only and featured a USB interface for updating transmitter lists. HDTM USB Plus updates are not available, but the scan functions still enable the meter to be usable.
HD-T2
The HD-T2 featured and extensive transmitter memory and a UK post code look up function to list near by transmitters. Spectrum and constellation modes were available along with logging functions. This model also featured a USB interface and supported DVB-T2 modulation. HD-T2 updates are not available at this time.