Opamps, in SOIC-8
Merged #1233 into master.
Stefan DK3SB, sent me this picture of his version of my frequency distribution amplifier. He modified the PCB to make it narrower (160mm), to fit a Hammond
1455R1601 enclosure (about 25 euros from Farnell).
Nice work! KiCad sources and gebers hopefully to follow, on ohwr.org
Update2: Here's the 14-hour data together with a 14-hour noise-floor run. The ADEV and TDEV results are more or less instrument-limited. Only for phase-noise above 100Hz offset is the instrument floor significantly below the result for the distribution amplifier.
Update: Here's a 14 hour run of the residual phase noise, ADEV, and TDEV, as measured through the frequency distribution amplifier. Instrument is a Microsemi 3120A phase-meter.
Aivon has now produced around 16 of these distribution amplifiers.
Update: Molex R/A 'long-neck' SMA-connector:
I sumbitted a few pull-requests to the KiCad libraries with some parts used on recent boards. Let's see if/when they make it into the main/released libraries...
On the to-do list is to submit an SFP-connector and Cage footprint... (unless someone has already done that?).
Inspired by discussion on time-nuts, here's a revised noise-colour graph. There are a few updates: The PSDs (both phase and frequency) now cross at 1 Hz (with the relation between phase-PSD and frequency-PSD explicitly stated), and the ADEV/MDEV theoretical lines now include the formula for the pre-factor (the old graph only had 'proportional to' here).
It is left as an exercise to the reader to properly explain the ADEV pre-factor for flicker-phase noise :).
Might be some of the last weekends this season for biking in decent weather... Mostly easy but hilly gravel paths from Oittaa heading north to Solvalla, then back south along the main road.