13cm Transverter for GM0USI
2 minute read
September 2008
13cm transverter internals
Over the summer, if you can call it that, I built a 13cm transverter for Alan, GM0USI. This is a 12V (nominal) version of my own transverter, who’s PA runs from 26V. The 12V PA is effectively the same, but apparently optimised for 12V operation. Like my own transverter, this one is based around a DB6NT 144/2320 transverter built from a kit . . . But unlike my version, which is built into two back-to-back boxes, I decided to build Alan’s one into a single box ... See the photograph on the right.
Like the 26V PA, the 12V version gets very hot due to the nature of it’s Class-A design and thus warrants considerable cooling. This is achieved by mounting fans at both ends of a length of substantial heatsink and then enclosing the open fins creating a cooling tunnel through which air is forced. There is a temperature related voltage output from the PA board and this is used to control the temperature at which the fans come on.
On seeing the finished product, and comparing it to all my own transverters, Alan commented that it was almost as if I had set out to create a brand image. What Alan was referring to is the fact that on my home-brew equipment, the front panels are always black, and the LEDs are always in the same location. This gave me an idea ...
I suppose this is nothing more than pure self indulgence, but I do like the effect!
The job of painting the box fronts was no easy task considering that all the switches etc. had to be removed from the front panels. To recap . . . and from top down ...
Sound-Card Interface ...
144MHz I/F Routing Controller ...
Transverter Controller ...
HF Routing Controller ...
And finally my RF Speech Compressor.