|
I have just recently built my own unit that is based on the #5 unit you have looked at, it is basically a 555 timer controlling the duty cycle of the power transistor.
I did add a heat sink though but when it's running only one heater it hardly gets warm.
I'm about to make a set of four mounted in the one box as it has been so successful.
Two scopes finder and eye piece, should be good.
|