TM4 Radios (Legacy)
In order to increase performance and reduce price, Racelogic have released a number of different telemetry modules and DGPS base stations. Local restrictions on radio use have also required the production of European (E) and US (U) variants of the telemetry modules. For these reasons, VBRTM4E telemetry modules may only be used with other VBRTM4E modules, VBBS2/4Es and VBBS3G/4Es; VBRTM4U telemetry modules may only be used with other VBRTM4U modules, VBBS2/4Us and VBBS3G/4Us. Operation with unit types other than those listed is not possible. Please contact Racelogic or your local VBOX distributor if you wish to purchase VBRTM3E or VBRTM3U modules for use with older equipment.
Due to the frequency-hopping nature of the VBRTM4U (required by law for US operation), the performance of these modules is lower than that of the VBRTM4E. In particular, the amount of data that can be transmitted in a given timeframe is lower. For this reason, it is necessary to reduce the amount of serial data output by the VBOX, either by reducing the serial rate or by reducing the number of channels sent via serial.