QRPGuys TCXO Frequency Standard/Reference – $20
The QRPGuys TCXO (Temperature Compensated Crystal Oscillator) Frequency Standard/Reference is a handy self-contained frequency standard accurate to 2.5 ppm. The output frequency can be jumper set to 10, 5, or 2.5 MHz. The TCXO on the board has a trimmer that you can set and calibrate to WWV. It is powered by a 9V battery on the board, with a female BNC connector for the ~ 3V p-p output. A welcome addition to your hamshack. On a difficulty scale of 1 to 5, 5 being the most difficult, this is rated at 2 or 3 depending on your experience. 9v battery not included.