Judging by the sourceforge statistics, we actually have a sizable user base!!! (EEEK!!!)
I have not been able to fix the current branch. =((( And I'm going crazy without a working ktechlab to play with my brainstorms!! =((( I finally figured out how you are SUPPOSED to use transistors for IV conversion... Current mirrors can bite me, they're a fucking awful design!!! A transistor is inherently a current amplifier. To use it with a current output DAC, you need to find one with an extremely low Hfe (between 20 and 100 depending on the chip) and base resistance, bias it negative, and then put a really low load resistor in the collector circuit, if you have a differential output DAC, make a differential amplifier with a quarter to half an ohm in the emitter circuit... At least that's what ktechlab is telling me to do. =P The transistors will need to be as linear as you can find and good for at least 500mW of dissipation, possibly even heat sinked, the power supply will be putting out some pretty heavy current! =P The secret sauce is to hold the emitter circuit at -900mV. =P Since the impedance of this circuit is extremely low, you don't need an output buffer of any kind, so you have a one or two transistor circuit instead of a pile of opamps with dozens of transistors in each... I'm not saying this approach will technically outperform the opamp solution but it is definitely the "purest" approach to the problem. Your only other option is to use a 417 tube in the grounded grid transimpedence configuration. That may not be as good though. =\ I think it might be a good idea to go through my commits between Saturday evening and today and roll back some of the more drastic ones and hopefully at least make connectors visible again! =( I don't have enough skill with SVN to do this myself. =( I really do want to keep some of the changes, especially a few that exposed some latent segfaults, but I really need to do what's necessary to make it usable again. =( I'm looking at the SVN logs, the last "normal" commit was 309. Here's a keep/chuck list for the other commits. 310 was the one where I unmasked the bugs... (probably/hopefully keep.); In retrospect, I should have made these changes one at a time... =( 311 simulator cleanup. (almost certainly keep) 312 (keep). [[ this is where I made my big mistake of trying to clean up/refactor the Connector heirarchy in hopes of isolating some of the de-refferencing deleted memory bugs.. ]] 313 -- chuck/revert 314 keep 315 -- chuck/revert 316 -- chuck/revert [[ I then comited far too much of my failed refactoring attempt and got myself stuck in a big old hole...]] 317 -- maybe keep 318 -- would be nice if we could keep. 319 -- maybe keep. 320 -- revert 321 -- revert (see earlier). 322 -- revert 323 -- revert 324 -- revert Maybe I should waste my time breaking the KDE4 build... Can that be put in SVN pleez? -- New president: Here we go again... Chemistry.com: A total rip-off. Powers are not rights. ------------------------------------------------------------------------------ The NEW KODAK i700 Series Scanners deliver under ANY circumstances! Your production scanning environment may not be a perfect world - but thanks to Kodak, there's a perfect scanner to get the job done! With the NEW KODAK i700 Series Scanner you'll get full speed at 300 dpi even with all image processing features enabled. http://p.sf.net/sfu/kodak-com _______________________________________________ Ktechlab-devel mailing list Ktechlab-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/ktechlab-devel
