i just wanted to thank you for this post. as soon as i read this i emailed vexilar , and found out that my locator which i just bought is one with the problem .i am posting what they told me.if your fl-18 serial number is less then 192501 and there is no v2 marking on the back of it , we have newer software code available. the new code solves a situational problem with bottom content and or targets in the area. under certain coditions, the bottom reading on the zoom will jump up some distance everything still works except the zoom zone becomes smaller the unit may correct itself or you may need to turn it off and then on again to reset it . so far ,this appears to be phenomenon specific to certain soft/hard layered bottoms or very weedy or very rocky conditions. the az may act up in one spot ,but work perfectly in another .i live close to there service dept. and i will be taken mine in to get the software up grade . here is the address if anyone else is intersted . vexilar,inc attn fl18 update
200 w 88th st #10 mlps mn 55420 they also told me that if i bring it in . it will tak about 5 mins to fix . hope this helps someone . good luck and safe ice fishing to all