Several years back, I switched the Gretsch filtertrons out of my anniversary (work done by a professional) and replaced them with magnatrons. Yesterday I was going through my parts drawer with the idea of using the filtertrons for another project. Only probem is, the tech did not label which one is bridge and which one is the neck. There are no distinguishing marks on the bottom of either pickup, and as expected both covers have only the Patent number on top? Can anyone help?

Are they vintage or modern?
I don't know the modern ones but the vintage ones basically are the same for both positions. I would put the stronger one in the bridge position.

Do they have white or black insulating wire? I've had a couple of sets with the white=bridge and black=neck. As mentioned, there isn't much noticeable difference between the two in the modern hs Filtertrons. I've had two bridge ones in my 5120 before I realised... Didn't realise until I removed them.

Test the ohmage with a multimeter, the higher one is the bridge. Having said that some guitars have the same value for both. I bought a Korean Dano with seymour duncan lipsticks in & although they were labelled bridge & neck they metered out the same.

Pardon my noobness, but doesn't the neck pup have ears that stick out past the cover on each side?

Pardon my noobness, but doesn't the neck pup have ears that stick out past the cover on each side?

That's what i thought. The neck-pu is a little higher too, if i remember correctly.

Didn't notice the wings.....I will have to take a look

Is there any difference in the pole spacings, I can't generalise but with the TV Jones set I've got the bridge poles almost touch the casing where as the on the neck pickup the poles are postioned slightly away from the casing so as to sit directly under the strings.

Check the length of the leads...sometimes the bridge unit has a longer lead...if the wires go up to the selector switch on your model.

The neck will be in a shorter cover, not taller, and I think that only applies to vintage and TVJ types...not the modern RI versions. Both units could have ears, that means they are for hollow body applications...without ears means it was meant for solid body or possible jet body applications or somebody just ordered them from TVJ without ears...a short base. The RI may all have short bases too. So many variables.

Like some mentioned above...meter 'em and stick the hotter one at the bridge.

I sorted it out by looking at the pole spacings.....thanks to everyone for your help

Welcome.