My 250 has the stock 6.5"X9" coil, and the new 350 the DD coil. Both detectors were assembled the same by having the cable wire-tied straight-up the lower stem, then wrapping the upper stem before making the connection at the housing. Both detectors with fresh batteries, All Metal mode, and 4 bars sensitivity.
250
Newer Nickle 5"
Clad Penny 5"
Clad Quarter 5"
Large mens silver ring 5.5"
Silver dime 5"
Wheatie 5"
Silver Quarter 5.5"
350
Newer Nickle 5"
Clad Penny 4.5"
Clad Quarter 5.25"
Silver Dime 5"
Wheatie 5"
Silver Quarter 5.5"
Same large silver ring 5.5"
Now, I swapped coils.....
250 with the 350DD coil
As soon as I powered-up the machine with the same settings (4 bars sens, all metal mode), it went nuts (jumping and dinging all-over the scale) until I backed sensitivity down to 2 bars, then it stopped. So note both the following tests were done at 2 bars sensitivity.
Silver Dime 2.5"
Silver Quarter 3.5"
Clad Quarter 3"
Large silver ring 3.5"
350 with the 6.5"X9" coil from the 250
It didn't have the problem noted above (jumping around/going nuts), however I still lowered sensitivity down to 2 bars for an equal test.
Silver Quarter 2.5"
Clad Quarter 3"
Large Silver Ring 3"
After seeing the major loss of depth on the last 2 tests (swapping coils), I didn't bother conducting all the tests I did on the 1st 2 (leaving factory coils on their respective machines), again, because to me it's obvious they don't work well together when swapped.
Take this for what it's worth, but I'll never swap coils in hopes of some sort of benefit......there are none.
Smitty
250
Newer Nickle 5"
Clad Penny 5"
Clad Quarter 5"
Large mens silver ring 5.5"
Silver dime 5"
Wheatie 5"
Silver Quarter 5.5"
350
Newer Nickle 5"
Clad Penny 4.5"
Clad Quarter 5.25"
Silver Dime 5"
Wheatie 5"
Silver Quarter 5.5"
Same large silver ring 5.5"
Now, I swapped coils.....
250 with the 350DD coil
As soon as I powered-up the machine with the same settings (4 bars sens, all metal mode), it went nuts (jumping and dinging all-over the scale) until I backed sensitivity down to 2 bars, then it stopped. So note both the following tests were done at 2 bars sensitivity.
Silver Dime 2.5"
Silver Quarter 3.5"
Clad Quarter 3"
Large silver ring 3.5"
350 with the 6.5"X9" coil from the 250
It didn't have the problem noted above (jumping around/going nuts), however I still lowered sensitivity down to 2 bars for an equal test.
Silver Quarter 2.5"
Clad Quarter 3"
Large Silver Ring 3"
After seeing the major loss of depth on the last 2 tests (swapping coils), I didn't bother conducting all the tests I did on the 1st 2 (leaving factory coils on their respective machines), again, because to me it's obvious they don't work well together when swapped.
Take this for what it's worth, but I'll never swap coils in hopes of some sort of benefit......there are none.
Smitty