I have never hunted the beaches with a F75 or T2. I use a dedicated beach machine for that..
I do know you have to manual GB the F75 for Salt water beaches. as The fast Grab will not do it... I also know it is hard to go from beach sand ( Dry) to wet black sand on any beach with the F75's..
I'm not saying you can not use the 75 on a beach. I'm only saying that is not a specific use built into the detector..
[size=x-large]Fisher says...........................[/size]
All Fisher Research Labs searchcoils are waterproof, allowing you to search in shallow water about two feet deep. If searching around water, be careful not to get the electronics housing wet. Avoid salt spray, as it will work its way into the control housing and damage the electronics -- such damage is not covered by the warranty.
Both fresh and saltwater beaches are popular places for metal detecting. Vacationers lose money and jewelry playing in the sand and in the water. It is usually easy to dig in a beach environment, and metal detecting is permitted on most beaches. Occasionally you may be able to help someone recover a piece of jewelry they have lost minutes before; this is a gratifying experience.
When searching on a beach, it is best to either search in Motion All Metal mode, or to search with the discrimination level set just high enough to eliminate iron, because the value of beach finds is largely in the jewelry rather than in the coins. You will dig a lot of aluminum trash, but the digging is easy, and you can tell people that you are helping to clean up the beach and make it safer for people's feet. We recommend the use of a special sand scoop for recovering valuables from the sand quickly -- most metal detector dealers sell these.
The electrical conductivity of the water itself can pose some challenges. You may get false signals when going into and coming out of the water, making it necessary to pay careful attention to keep the coil either in or out of the water, but not to touch the surface. This effect may be observed in either fresh or saltwater.
Saltwater Hunting
Saltwater is highly conductive, and produces a strong signal which is like that of metal. [size=x-large]The F75 is not specifically designed for high performance in saltwater, but can be used in this environment[/size].
If you desire to search in or over saltwater, the following measures will usually be sufficient to silence the saltwater response while retaining acceptable sensitivity: 1. Set the sensitivity in both modes to less than 30. 2. Ground balance the machine manually in Motion All Metal mode. 3. Search in the Discrimination mode with a discrimination setting higher than 25.