Excal & SEF coil - unstable threshold

[SandSweeper]

I have had an Excalibur 800 for about 4 yrs. I've never had any problems w/ the Excalibur, on Carolina beaches, its as steady as a rock. I mainly search the

areas from the high tide mark, dn to the trough. The biggest compaint is w/ the 8" coil, it like scrubbing a hall way w/ a toothbrush.

I have it hip mounted & w/ a straight shaft so, weight is not an issue. When everyone started talking about wiring the Excal's w/ the Sef coil - I'm there, I'm on

it, w/ both hands & 2 feet. I ordered the 12x15 sef BBS coil & a coiltek water proof connector (wiring it straight into the excal, after watching the video on youtube,

I decided not to chance it , plus if I didn't like it, I didn't have to break into the machine a 2nd time).

The 8" coil vs 12x15 SEF coil (for the Sovereign / Excalibur) - compare a dinner plate to a trash can lid - I couldn't wait !! I cut both coil wires, wired it temporarly

to check for function. I got good sounds on test targets, my threshold is functional, although it does not hold rock steady. I contribute the small fluxuation in the

threshold to back ground noises - alot of double 8' fluorescent lights, power strips, desk top computer in my work shop, etc. Coil as big as a sheet of plywood. HA

On the beach, the threshold is holding steady, solid hits on target, LOTS of bikins, life is GOOD. It's like going from a push mower to a 54" riding mower!!

WELL, approx. an hr later, it starts falsing like crazy. I adjust my sens, from hot to auto & back, everything - left / right - forward / back. Even w/ the treshold

lowered WAY dn - past where its normally silent - its still going bananas.

Time for a break, I go sit in the shade w/ a whiskey sour, lots of bikins - (Explorer SE back up) lifes still good. After a few drinks, I grab the Excal & go at it again

Its good as gold, I couldn't ask for better. About the time I figure the problem was cosmic radiation, solar flare, blip in the magnetic field, it happens again!!

For the rest of the weekend, the Excal sets quietly in the corner - FAR AWAY from my SE... Looking for any clues - Thanks Findmall.

P.S. I reposted w/ a shortened title so the "unstable threshold" would get noticed

 

[OldBeechnut]

I just put a SEF on a Excalibur ..10 x 12...has issues, also. I know of 2 other people that have had issues, just like your with the SEF, but the smaller 10 x 12. Maybe they just don't work on some excaliburs...I have done several air test with all the excaliburs I have repaired....seems all are created different....ranging from 1 to 2 inch's difference......stablity on each is very close, until you put a bigger coil on them, then they seem to pick up to much surface condition ....will get back to you on this, dinner

 

[Critterhunter]

Wow, I just got done saying I've never heard of any SEF issues on Minelabs with stability problems or such, then you post this. As far as the depth of various Excals...Weren't the earlier ones based on the XS, and then later models were based on some later Sovereign like perhaps the Elite or something? If so, that might explain the depth differences perhaps between Excals?