This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
SWTPC Frequency Counter. SWTPC Digital Measurements Lab with Frequency Counter plugin Designed by en Daniel Meyer Published in en Popular Electronics in November of Sold as three kits Cabinet and Power Supply Multidecade Nixie Readout Frequency Counter Plugin Also offered were Digital en Multimeter Digital Thermometer and