Not being a writer, I found this undertaking to be something short of impossible. But, being a ham fortunate enough to have two or three home spun circuits that work very well, I felt 1 had to share my joy with others.

The units described here are all based on the use of inexpensive plastic FET's- The designs are by no means mine but rather ideas collected from many sources. The principle source, and that which prompted my experimentation with Ft 1 \ was an article written by W6AJF, Frank Jones, in the Sept. issue of 73 for 1968.

My first endeavor was to construct a pre-amp for 436 MHZ A I V. Being primarily interested in signal gain, 1 constructed a two stage unit employing the Union Carbide UC734E epoxy field effect transistor. This unit consisted of a neutralized grounded source coupled to a grounded gate. 1 used sockets in this unit mainly because I am new at transistor construction and didnT want to damage them while soldering. Also, as Mr, Jones points out, this allows the selection of tlic hest transistor for the first stage. I also shielded the drain from the source on both transistors and this proved to be very useful in preventing feedback.

0 0

Post a comment