New power switch for Maverick Redi-Chek ET-73

The Maverick ET-73 Redi-Chek wireless meat and pit thermometer is very popular with egg owners since it works so well and is reasonably priced, however many people are frustrated that you have to remove the battery door cover to turn the transmitter unit on and off. This was an intentional design feature because they wanted the transmitter to be weatherproof and it would have been harder to incorporate an external power switch without introducing moisture inside the case. So like many other ET-73 users I have been tolerating this minor annoyance until now.



I recently came across a small battery powered light which is designed for installation inside a cupboard or drawer. This unit was only $1 at the local Dollar Tree store and it can be found at other discount stores including Walmart and Big Lots. It contains a small magnetic switch that turns the light on/off when the cupboard is opened and closed.



I decided to remove the magnetic switch from the light and install it in my ET-73 transmitter to function as an external power switch. Here is how I did it:

Pry open the light housing and look for the thin magnetic switch which is aligned with the side of the case in the area shown below. It looks like a tiny glass fuse and is about 1” long with a thin copper wire on each end.

Remove the magnetic switch from the light with a soldering iron or wire nippers. Be sure to leave enough copper wire on each end of the switch for installation in the ET-73.



Open the ET-73 case (six screws) and remove the circuit board from the housing (4 screws). Be careful not to lose the small black rubber seals or the gray TX button plunger.

Solder a short 2-conductor wire to the back of the existing ET-73 power switch. The wire should be about 5” long and no thicker than 22 awg. I used a short piece of twisted pair wire cut from an old CAT5 ethernet cable.



Reinstall the circuit board and solder the other ends of the wire to the magnetic switch, then glue the switch to the inside of the ET-73 case along the top right edge.




Reassemble the ET-73 making sure to align all of the rubber seals and the gray TX button plunger.

Now you can turn the ET-73 on by holding a small magnet to the outside edge of the case. I applied a thin strip of velcro to the magnet that came with the light and it works just fine. If you have a custom mounting bracket, case, or shelf for your ET-73 then you can attach the magnet to it and the transmitter will automatically turn on whenever you set it in place next to the magnet. You can also still use the original power switch inside the battery compartment if desired.




This was a quick, cheap, simple project and it makes the ET-73 a lot easier to use especially when I am wearing gloves or need to reset the transmitter. Hope someone can use this info.