Horn test
Griff
He's also right about the wire size - should be 10 ga at least.
Here's a couple more things to consider. If you are talking about trumpet horns, they pull and amazing amount of amperage. You MUST ensure that not only do they have a good ground, but the ground is substantial enough to pass the current. If they are hood mounted, this includes the hood being grounded enough.
Eventhough they were designed to be used with 6 volt positive ground, they can be used with 12 volt negative ground with no problem - they're just louder - darn!
If the gauge wire going to the horns either from the relay (which you MUST install to prevent welding your horn button parts together) or from the battery to the relay (via whatever path it takes - through circuit breakers or fuses or ignition switch, etc) is not large enough, there will not be enough current flow to sound the horns.
Also, unless the old harns have been used recently, are clean and lubricated properly, they probably won't sound. There is a blued metal diafram inside that vibrates (its a big DC buzzer) and it wont vibrate if it is rust covered.
Lastly, the trumpet horns were adjustable. If they are dirty or rusty, or the contact points are burned they may need to be filed or adjusted to sound. The procedure is in the shop manual.
I have two sets of them on my 51 and I had to enlarge the power wire from the alternator/ignition switch link up to 8 gauge to get those four to sound.
But, there isn't a little old lady driving her Buick in Rancho Bernardo who will ever be the same since I moved here!
Note how visible the wire is - it's a biggie!

Here's a picture of the Horn Button set up just as a check:
PS: Be careful when touching the wire to the battery. I might be tempted to attach a set of jumper cables to the battery, and connect the grounded cable to the horn body, then touch the power wire to the power stud some distance from the battery to prevent a possible battery explosion or fire - it's gonna be a BIG spark! And don't hold it. No matter how prepared you are for it, it's gonna blair out, vibrate, make brown fog, and make you jump!
How to Restore a Classic Car Horn
It also has an article on a 52 F1 Ford rebuild

SCG Classic Car Restoration: 1952 Ford F1 Pickup Truck Restoration Project
Don't remember how I found this site

Dale
Ford52F2
You MUST ensure that not only do they have a good ground, but the ground is substantial enough to pass the current. If they are hood mounted, this includes the hood being grounded enough.
If the gauge wire going to the horns either from the relay (which you MUST install to prevent welding your horn button parts together) !

But, you can check the actual function of the horns as I described above with the jumper cables in answer to your original question.












