Temperature logger

Hi
I'm looking for programable temperature logger, it should measure temperature underground and outside, I would like to configure it to measure and record temperature for example, every hour for about a week long, I'm looking for cheapest and simplest logger.

Welcome to ETO, qweeqweqew!

To build or to buy?

Your idea of simple and cheap may not be the same as my idea of simple and cheap. LASCAR has what I see as an inexpensive line of temperature and humidity data loggers. They also make temperature only units I believe and units that allow for an external temperature sensor like a thermocouple which could be buried. Dataq Instruments is a US distributor of the LASCAR products as well as others. Something like this may work for you, Single Channel Thermocouple Data Logger Supports TC types K, J, and T. You will need to get a sensor and interconnect thermocouple wire. I use these to record temperature and humidity over extended periods (weeks) in a gun safe. They are easily programmable using any PC USB port and include the simple software.

Ron