Ghostbusters 2 KUD Meter

The KUD Meter is one of the more esoteric props from Ghostbusters 2. Even Ernie Hudson (the actor who played Winston) doesn't remember using it in the movie.

Screencap 1 Screencap 2 Screencap 3

So the first thing was to find the parts. The main piece is a relatively cheap Radioshack metal detector. I managed to find a broken one on Ebay for $10. It's not the correct model but for the price it was close enough for me, especially when most people don't know it was even in the movie.

Stock Metal Detector Body Closeup Body Side

The other main parts are a potato masher and a strainer which give the KUD(kitchen utensil detector) meter its name. These were surprisingly hard to find. After weeks of scouring local thrift stores and flea markets I wound up getting a "close enough" potato masher at Target and swapping my mom's old metal strainer for a new plastic one.

The first task was to look over the metal detector. It turns out that it wasn't as broken as the ebay seller thought. Someone left old batteries in it at some point which leaked and corroded all the contacts. A bit of work with some files and an X-acto and the meter worked like new. Then it was time to crack it open.

Coil Connection Power Switch Coil Removed Coil Connection Side

I wanted to try and keep the induction coils intact so it would still buzz and "detect" so I made sure to document all the connections before changing anything. I then carefully went about removing the coils from the plastic housing. The wire that ran from the body to the coil was cut and the connections were re-soldered so it would fit inside the body. To make space I removed the earphone jack from the board. I found out later that there was a connection inside the jack that was required for the speaker to work so I installed a jumper to make the connection. I also replaced the battery test switch with a more screen accurate silver toggle. It was a bit of a pain in the ass to make it fit but eventually it worked out.

Fitting Electronics Masher Attached Jumper Connection

The whole thing was rather fiddly and several of the coil wire broke. In the end the meter doesn't "detect" anymore but the needle moves and a stuttering buzz is emitted when the red button on the handle is pushed so it gives essentially the same effect. After prepping and installing the potato masher the next thing to do was the blinking red light. I tossed together a simple circuit with a 555 timer. This was piggybacked onto the on switch for the detector to run off the same batteries.

Blinker Circuit Spliced Connection Modified Switch

Once everything was tested I secured all the loose wiring with hot glue and electrical tape. For some reason the speaker is temperamental and will stop working if I tighten the case screws too much. They're still tight enough to secure it though so I'm not worried. I have a feeling it would work just the same without the coil wires at all but I'd rather not screw it up testing the theory for now.

Finished KUD Left Side Lit Indicator Right Side

I'd like to figure out some kind of shoulder strap for it as it's a bit heavy with 6 AA batteries and stainless steel utensils riveted to it plus having to hold it all the time can get to be a hassle. There's no good place to install a D-ring and hanging it from a belt loop would probably damage it. All in all I'm happy with it for now, it's got blinkenlights and makes noise which is all anyone could want in a Ghostbusters prop.


In 2014 I acquired an accurate metal detector and decided to upgrade this prop.

New Parts

I got a new strainer and potato masher and built another blinking light circuit. I then assembled the new KUD the same way I made the old one above.


So now I have an accurate version of a prop no one cares about!

Finished KUD

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