1.3GHz Transmitters

Television transmitters for use in the 1.3GHZ band usually generate their frequencies directly at the desired output frequency. One of the most common designs is made available from the Worthing and district video repeater group. The design that they continue to market and support was designed by Alan Latham G8CMQ he ran a company called Solent Scientific. This design has been available for a number of years and offers good value for money, you can also add on a 2-channel phase locked loop. This addition allows you to have two xtal-controlled channels. Most local amateurs have one of these as the repeater input frequency say 1249mhz and one as a simplex frequency such as 1255mhz for local working. Construction at these frequencies can be a little tricky for the beginner, but most groups have someone available to offer help and assistance.

The BATC also sell a PCB for construction of your own transmitting equipment, a full kit is available from Mainline Electronics of Leicester.

This design in it's present form has a free running oscillator stage and produces approximately 1W output from a solid state power module. Power modules are a very cost effective way of producing power output in the 23cm band.

The price of these modules are not expensive (Approx. £75) considering the simplicity of their use, which requires only a handful of external components. They are very rugged and stable, and do not exhibit any of the of the sensitivity to handling of some Pa's. However, they are only about 25% efficient and must therefore be very well heatsinked if overheating is to be avoided. The SC1040 at full output will liberate about 50-60 W of heat. However, if kept cool by adequate heat sinks (which may be fan cooled if necessary) they will operate at these power levels for literally years as the operators of GB3ZZ will testify.