GPSDO, sub-ppm frequency accuracy in your home lab
Combining very low drift of readily available (second-hand) OCXOs with a GPS receiver for a calibration-grade frequency reference in your home lab.
Several prototypes of MarME’s design of the GPSDO
Initial Prototypes
For lowest jitter a GPS receiver dedicated to timing (LEA M8T) was used
GPS Receiver
Measured on a counter with ultra-stable OCXO option a deviation over 900 s is shown of only 1.1 mHz on 10 MHz
10 MHz stability
Repair of an HP 8591E spectrum analyzer
MarME obtained a broken HP 8591E, with the message it had a strange glitch in amplitude. This turned into an extensive repair, finding three different faults in the same unit. Apart from a fried input attenuator and some strange bodged-in resistors, a lot of the calibration trimmers needed new alignment.
Athlete Analyzer
An Android app, built together with Claude, that measures jumps, sprints and barbell lifts from a phone video, and states the measurement error next to every result. Work in progress.
Custom R&D
An overview of different R&D projects
Custom microphone amplifier
For electronic starter signals during track & field events, a battery-powered amplifier was requested. Gain and single-ended-to-differential conversion.
Tube amplifier with Nutube
Preamplifier with multiple inputs using Korg Nutube
Strain monitoring
Custom project making a wearable used to monitor lower limb impact
Custom R&D projects
Working together on custom R&D projects respecting your wishes.