On Wed, Nov 01, 2006 at 10:58:02PM -0500, DJ Delorie wrote: > > > It all depends on what you're into. I've been discussing a > > project with a friend that would involve building what amounts to a > > copy of the PDP-8 ("Straight-8", no suffix) with individual > > transistors. It's fun, cool, and highly educational in a number of > > areas.
Now I am rebuilding the Ronja receiver with individual transistors instead of the NE592. The dynamic range was low, the chip operated out of the specified thermal range and you had to pick up transistor pairs with similar amplification. Only now I discovered the beauty of symmetric limiting amplifiers, current sources and cascode configuration. Now I have two stages, the first is 4-transistor and the second 6-transistor. I want to make 3 stages, 6 transistors each and today I have to go into a shop again for another 10 transistors, because I have just 1 left here. Transistors are cheap. Transistors are fast. Transistors have almost unlimited operating temperature range. The manufacturer doesn't keep the secrets of operation away from you. You can implement interesting functions by clever arrangement of them. I am looking forward to the day when the receiver will be finished and I can place a "fully transistorized" and "19 transistors" retro labels on them :) Finally people will stop asking "where can I get that NE592 circuit" and "my Ronja doesn't work on short distances". Does it matter if you solder 14 pins of NE592 or 5 3-pin transistors? CL< > > Are you going to be true to the time and use TO-92, or "cheat" and use > SOT-535's? > > The Museum of Science in Boston has a computer that plays tic tac toe. > It's made of wooden Tinker Toys. > > > _______________________________________________ > geda-user mailing list > geda-user@moria.seul.org > http://www.seul.org/cgi-bin/mailman/listinfo/geda-user _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user