We've got a new GPS receiver module in stock, on special this week for $36:
https://www.argentdata.com/catalog/product_info.php?products_id=137 They've very easy to integrate, with TTL and RS-232 outputs and 3 to 5.5v supply. We've got another module due in soon that's not as small, but has firmware designed specifically for high-altitude applications. I'll post another announcement when that one's available. Scott
