THE PA3CEG
23 CM GS35b PROJECT

This project was based on the latest information (April 2001) from Alex RW1AW. Some of the tubes dimensions in the cavity where hard to find, so they where made from massive material. Its takes a lot of time to make all the parts from sketch and finish them for assembling. Special attention, to optimize the airflow in the cathode compartment to cool down this part of the GS35b. Planning to cool  the air stream later on with a Peltier element, otherwise water cooling must also be possible. There is a lot off heat to exchange, due the low efficiencies on 23 cM.

EDITOR'S NOTE: Four attempts by four independent amateur radio operators to build this amplifier have resulted in similar results - about 600W output with detuning problems associated with thermal drift. We all hope Eene PA3CEG is successful at "taming the beast" - HI!! Caveat emptor!

dual-PA-a.jpg
dual-PA-a.jpg
23cM-GS35-compl1.JPG
23cM-GS35-compl1.JPG
23cM-GS35-compl.JPG
23cM-GS35-compl.JPG
23cM-GS35-compl2.JPG
23cM-GS35-compl2.JPG
GS-cap-a.jpg
GS-cap-a.jpg
23cM-GS35-compl5.JPG
23cM-GS35-compl5.JPG
23cM-GS35-cool2.JPG
23cM-GS35-cool2.JPG
23cM-GS35-cool8.JPG
23cM-GS35-cool8.JPG
23cM-GS35-cov1.JPG
23cM-GS35-cov1.JPG
23cM-GS35-compl3.JPG
23cM-GS35-compl3.JPG

After a few tests, the air cooler was changed due the distance (air gap) between cavity and cooler for proper cavity tuning.

See the part and construction details


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