How to Upgrade Your ESP8266 SPI Flash to 4MB

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https://www.electronics-lab.com/upgrade-esp8266-spi-flash-4mb-one/

ESP8266, the well known WiFi module contains an ESP8266EX SoC IC and an external SPI flash. This external SPI flash is used together with ESP8266EX to store user programs. The supported size of flash by ESP8266EX is up to 16MB but some of ESP8266 modules contain flash chips with low storage capacity like 512KB. In […]

Fluke/Philips PM66xx Frequency Counter OCXO Upgrade

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https://www.electronics-lab.com/flukephilips-pm66xx-frequency-counter-ocxo-upgrade/

In this post Dan Watson documents an OCXO upgrade board he designed for the Fluke/Philips PM66xx line of frequency counters. A few months ago I purchased a Philips PM6674 frequency counter on eBay. It’s an older 9 digit counter with two channels that has a maximum input frequency of 550MHz. The design feels dated compared […]