Work has begun in earnest to completely rebuild the Collins 30S1
amplifier using a novel approach. The plan is to maintain the exterior
aesthetics so it will appear to be a stock Collins but completely replace
the power supply and tube complement to achieve high power. All of
those components have been removed. The RF deck has been completely
gutted except for the tuned input and pi-net circuitry. The front panel
remains intact. If you visit the site listed below, the basic power
supply components are depicted. What will be apparent immediately is the
small space required to achieve the plate voltage of 5000VDC@ 2 amps.
The complete doubler rectifier, filter board with bleeders have been
fitted to a 6x9" board and nested above the pole pig transformer. I need
the current form that boat anchor to run the two planned tubes. I'll
maintain the choke input but will install a fully adjustable step start
option with a solid state delay timer for the Russian GS35S tubes. Great
tube, inexpensive to purchase, requires only a 3amp filament
transformer, almost identical characteristics to the 8877, but a bit
tall. In order to fit a pair into the Collins RF upper enclosure the
diagonal panel must be removed. I anticipate some problem there getting
cutting tools to fit in that limited space but it has to be done. As
work progresses, I'll keep you informed. Ron W2CQM/3
http://briefcase.yahoo.com/W2CQMron
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