Digital Temperature Controller Module HW-557 V9.0

Digital Temperature Controller Module HW-557 V9.0

Used - Good Personal Electronics Collection
$15 (rough estimate)

A digital temperature controller circuit board featuring a 3-digit 7-segment display, control buttons (SET, +, -), and connection terminals for sensors and power. Used for monitoring and regulating temperature by switching connected devices on or off based on set thresholds.

MRF905 RF Transceiver Module

MRF905 RF Transceiver Module

Used, some visible wear and oxidation on solder joints Unknown
$10 (rough estimate)

This is an MRF905 RF transceiver module used for wireless communication in the 900 MHz ISM band. It features a small PCB with an SAW oscillator, microchip labeled MRF905, and an SMA antenna connector. Commonly used in hobbyist and low-power RF applications such as remote controls, sensor networks, and amateur radio systems.