Both of my thermometers are Zoo Med Analog Reptile Thermometers, the one on the hot side is placed right at the base and the one on the cool side about 3 inches above the substrate. The probe is directly stuck on the heat mat. The heat mat is a habistat 11 x 11 and the thermostat is a habistat mat-stat.
I've even tried sticking one of the thermometers right on the mat and the highest reading I am getting is 88.
I'm using an aspen substrate about 1 inch thick with newspaper under it, but only a single sheet.
My digital camera has a completely dead battery (the last time I used it was like ... December) and needs to charge up before I can get pictures, but I'll try to post some later if the information I provided doesn't immediately flag up problems!
Thanks guys!