Peter, I have a Thunderbolt with the DS1620E temperature sensor that I would like to upgrade to to a C version. I think you said on Time-Nuts that you might have some of the C version chips. If so, how can I go about getting one or two from you? I’ll be glad to pay what you feel is reasonable. Thanks, Jim Hall W4TVI 7960 W Bayhill Ct. Boise, ID 83704