146 MHz RB-TV

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UK radio amateurs with full licenses have been given access to an extension of the 2mts band between 146 and 147 MHz but only for experimental modes. This is done on a temporary basis and you will need to do an on-line application for a NoV to your current license using this link:

http://rsgb.org/main/operating/licensing-novs-visitors/online-nov-application/146mhz-147mhz-nov/

The RSGB band plan now includes (and encouraged) the use of Reduced Bandwith Digital ATV (RB-TV) using 500 KHz centered on 146.5 MHz. For more info on Reduced Bandwidth Digital television (RBTV) take a look at this RB-TV special edition of CQ-TV.

RB-TV equipment for 146 MHz

RB-TV on 146 MHz is not possible using "normal" DATV equipment and requires the use of equipment developed specially for the mode. For more technical details take a look at our getting started guide to RB-TV. Getting Started with RB-TV

Receive equipment

Due to the very low symbol rate, normal Set top boxes and satellite receivers will not receive RB-TV. The BATC minituner project was developed specifically to receive RB-TV - more details can be found on this wiki page.

Unless you use the new Serit tuner with your minituner, standard satellite tuners will not cover 146 MHz and you will need an upconverter from 146 MHz to L band - you can either home brew the upconverter or use one of the following:

You will probably need a filtered pre-amp - this design has proven to work very well on 146 Mhz RB-TV:


Filters

146 filter.JPG

Power amplifiers

Sam Jewell G4DDK, 8W amplifier kits, pcb, manual etc. http://www.g4ddk.com/144MHz8WPA.pdf

Anglia Live, suppliers of Mitsubishi power modules http://www.anglia-live.com/products/rf-products/rf-discretes-modules/rf-mosfets/list/perpage/21/page/1

60W power amplifier pcb (available from G4DDK above) http://www.ifwtech.co.uk/g3sek/vhfdx/gm3sek-pa-module-board