- finding similiar anomolies between simple RMAA tests, Bruel-Kjaer tests and theoretical simulations.
- of interest, at the moment, is harmonic/reasonant-coupling of all the PC switching supplies.
- including the local switcher supplying the SB0460 CA20K1.
- appears its "buck-noise" is coupling to the SB0460 ground plane and causing crap to appear in analog sections, above 32khz.
- OSCON's seem to have notched most of the parasitics down, by about -5 to -8db, depending on harmonic frequency.
- LM385 was to set "worst case" model reference and behavior template.
back to FFT's, Bode's and sims....
- hope you manage to get your backup card and sockets installed.
- would be interesting if I could send you "mystery" op amps and give you an additional headache. LOL
- and rock on with your "long leaded" by-pass stuff... planning to do a "long-lead" experiment to see interactions/coupling dynamics in a few days...
Picture: (new change: C72, OSCON 15uf @ 25vdc (-5vdc section)