Curious about what the “10 MHz” connector on the back of your test equipment is?  Interested in calibrating an SDR to reduce tuning error?  Do you want an accurate frequency source for tuning radios?  How about a super accurate sense of what time it is?  This week, Dr. Frank Howell K4FMH joins Jeremy and George to talk about GPS Disciplined Oscillators and Frequency References for your workbench. News Hurricane Watch Net - https://www.hwn.org/ Icom IC-9700 - http://qrznow.com/icom-ic-9700-vhfuhf1-2ghz-prototype-transceiver-shown-at-tokyo-hamfair-2017/ Circuit Board Printer - Voltera - https://www.voltera.io/ Circuit Board Printer - BotFactory - https://www.botfactory.co/page/homepage Workbench KF7IJZ’s Workbench Remote Airspy Server w/ ASUS Tinkerboard Airspy SDR Receivers Airspy R2 - 24Mhz - 1.8Ghz 10Mhz Bandwidth SDR Receiver - $169 - https://v3.airspy.us/product/a-airspy/ Airspy Mini - 24Mhz - 1.8Ghz 6Mhz Bandwidth SDR Receiver - $99 - https://v3.airspy.us/product/a-airspy-mini/ SpyVerter HF Converter - $49 - https://v3.airspy.us/product/a-spyverter/ ASUS Tinkerboard I Used a Tinkerboard because I had one, but I would recommend an ODroid device instead - http://www.hardkernel.com/main/main.php Tinkerboard Hardware - https://www.asus.com/us/Single-Board-Computer/Tinker-Board/ Tinkboard Linaro Linux Distro available on that page under Downloads Armbian Distro for Tinkerboard - https://www.armbian.com/tinkerboard/ Good review of Tinkerboard - https://forum.armbian.com/index.php?/topic/4614-asus-tinker-board/ Software Spyserver for ARM 32 Bit - http://airspy.com/download/ Airspy on ARM Instructions (do this first) - http://photobyte.org/running-spyserver-raspberry-pi-3/ Arduino MIDI Mute Button Hardware Adafruit Pro Trinket 5V - https://www.adafruit.com/product/2000 Adafruit 24mm LED Arcade Buttons - https://www.adafruit.com/product/3430 Adafruit MIDI Jack - https://www.adafruit.com/product/1134 Arduino MIDI Wirting and Communication Guide - https://www.arduino.cc/en/Tutorial/Midi Use “Debounce” Example code from Arduino IDE Arduino MIDI Message Guide (code is deprecated, but message formats are relevant)- http://little-scale.blogspot.com/2011/08/simple-examples-of-sending-midi-data.html Eagle Best Practices 1/16” Margin around the edge of the board Avoid acute angles on circuit traces Vias should be at least 0.04” in size Traces should be at least 0.03” in size Keep good space between signal lines and ground planes/traces Other Links Perseus SDR - http://microtelecom.it/perseus/ SDR Console Software - http://sdr-radio.com/Software/Download1/Download RF Space - http://rfspace.com/RFSPACE/Home.html Cloud SDR - http://www.cloud-sdr.com/ SDR# Tuner from Mouse - https://www.rtl-sdr.com/building-a-tuning-knob-for-sdr/   KJ6VU’s Workbench RIDGID Toolbox for KX3 Project - http://www.homedepot.com/p/RIDGID-22-in-Pro-Organizer-Black-222571/205440492 BBC Micro:Bit - http://microbit.org/   K4FMH’s Workbench Trimble based GPS GPSDO 10Mhz / 1PPS Clock - http://www.ebay.com/itm/Trimble-GPS-Receiver-GPSDO-10MHz-1PPS-GPS-Disciplined-Clock-sine-and-square-wave-/252162780444?hash=item3ab612ad1c:g:o2IAAOSw1WJZHdMY PCTEL GPS (L1) 26dB Timing Antenna Kit - http://www.ebay.com/itm/PCTEL-GPS-L1-26dB-TIMING-ANTENNA-KIT-GPS-TMG-26N-W-Mount-Kit-/263159662203?epid=1209248913&hash=item3d4589c67b:g:KU0AAOSw8gVX3BPx Six Output Video Distribution Amplifier - Sigma Electronics VDA-100A - https://www.ebay.com/sch/i.html?_odkw=SIX+Output+Video+Distribution+Amplifier+Sigma+Electronics+VDA-100A&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.XSigma+Electronics+VDA-100A.TRS0&_nkw=Sigma+Electronics+VDA-100A&_sacat=0 Leo Bodnar Precision 2 Output GPSDO (450Hz - 800Mhz) - https://v3.airspy.us/product/lb-gpsdo-1/ HP 3586A Selective Level Meter - http://ve2zaz.net/HP3586_AD5962/HP3586_AD5962.htm   Show Links K4FMH’s Blog - http://k4fmh.com WWV - https://www.nist.gov/pml/time-and-frequency-division/radio-stat