ka9s@ihps3.UUCP (10/12/83)
I am looking for schematic diagrams and parts sources that will enable me to home-brew solid state tube replacements for my old DRAKE C-line. Years ago I purchased four solid state tubes from Sartori Associates Associates, W5DA and placed them in my R-4C. They have worked fine and I have no complaints. At the time I corresponded with Howard Sartori about the Solid Tubes and was informed that he could not develope a solid tube that would perform better than the glass ( 6BA6 ) tubes. Around the same time Howard published an article in QST describing his Solid Tubes: "Solid - Tubes - a New Life for Old Designs by Howard J. Sartori W5DA QST, April 1977, page 45 " Since that time technology has improved ( namely the invention of VMOS ) and I have decided to convert as much of the old C-line to solid state as I can. I wrote Mr. Sartori to see what new products might be available and if he had any new designs he might be willing to share with me. Howard now has developed solid state tube replacements for all the tubes in the DRAKE C-line ( including the 6BA6 ) with the exception of the 6JB6 finals and the 12BY7A driver. He promises to have a solid state tube replacement for the 12BY7A some time this fall. The bad news is the price of the Solid Tubes ( $23.00 each ) which I find to be a little prohibitive. Secondly Howard is not giving out any design information for these new Solid Tubes. After reading over the article he wrote years ago, it appears that he is using some very high voltage solid state devices and I do not know where to purchase them. I also feel that there must be better designs around now that VMOS devices are available. If any of you have the designs or parts sources I need, I would appreciate some mail to the effect. TNX n 73's Jeff Goodspeed KA9S -- ============================================================================== Jeff Goodspeed, Western Electric Network Software Center, ihnp4!ihps3!ka9s (312)-260-4838
jj@rabbit.UUCP (10/12/83)
I suggest that you look through the Supertex and Ferranti Power FET lines. You might also consider combinations of a Depletion(naturally0 JFET and an Enhancement V-FET for tube replacements. I don't know of any useful depletion mode Power FET's, partly because the mechanism that most of the Power FETS use is easier done in enhancement mode. With a few circuit componenets, though, making single device replacements for many low frequency tubes isn't impossible. I recently hacked up a couple of power fet's into an old tube (audio) amplifier for the heck of it. There weren't any real complications other than the fact that I had to make the bias supply positive rather than negative. If anyone out there has more info on these tube replacements, let's hear it! I'm interested for other than tube replacement reasons. <sigh> -- O o From the pyrolagnic keyboard of ~ rabbit!jj -v-v- \^_^/