Greetings,
I'm working up a demonstration of an antique electronic temperature controller which needs a sensor with a PTC of about 5 to 6 ohms/degree F average (at 20 degrees C); nickel-iron resistance wire fits the bill fairly well, and I would like to find a coil on a low-mass substrate, like ceramic, of roughly 1150 ohms at 20 degrees C, hopefully no more than a few inches long (up to 5 inches is OK). I have some resistance wire salvaged from old soldering iron heater cores, but its gauge is a bit large such that to get 1150 ohms would require quite a lot of it on a rather large form.
Perhaps someone has recollections of small assemblies of resistance wire either used for heating, in the 10 to 12 Watt (at 120 VAC) range, or for sensing, that might come in at around 1150 ohms, so that I might avoid a tedious winding of hair-fine wire under magnification. Surprisingly (to me), my cannibalization of some 10 Watt heating tools (like hot melt glue guns) revealed not resistance wire, but some form of semiconductor with a NTC (isn't thermal runaway an issue here?).
Michael