Extech 380400 Resistance Decade Box

Solid resistor decade box, feels really nice on my hands, no a metal box but does not feel flimsy. Switches feel very solid, and all the switches external metal case are connected to ground. The yellow box looks nice on the bench. Does not take too much space.Some of these resistor decade boxes cost 100’s or 1000’s of Dollars, that’s crazy. Unless you are designing the next iPhone replacement, this is all you need. Resistor are 1%.The front panel cuts out are no precise. Look the 1MΩ switch, as a result the switch feels kind of rough when set to “IN” or “OUT.” This is the worse switch on the box I got. Some other switches are like that, but they don’t feel too bad.Overall, good box. I like it. I think 5 stars are well deserved. Price is good. Made in Taiwan. Where else, right?

A lot of time can be saved by substituting sensor resistance values to check circuit integrity. This tool has not only saved me time but has helped me diagnose some difficult automotive trouble codes by inserting known good solenoid etc values in circuits.

Works well I have used to it for testing of potentiometers and variable resisor circuits

Love being able to test automotive circuits with this thing. Beats sorting through my resistor box to find the right resistor for the job. The lead connections could be a bit more recessed into the unit like a multimeter but it doesn’t change its usability.

Super expensive but works great to control Trane Rtus in test mode and fake out resistors. Must have for HVAC tech. Countless ways to use this thing if you put your mind to it.

Perfect for my radio work

I measured the tolerance of each resistor. All were within 3%.

I use these to test line isolation monitors. When testing, I noticed the 20 ohm switch would fail the LIM. When I ohmed the decade box out I found that the 20 ohm switch would not show resistance. It was open. I had to retest two facilities after finding this which cost my company a lot of money.