F5 threshold question

Mezrein503 · Aug 3, 2011

hey guys, was just wondering if this might be a problem. I've had my F5 for about 2 months now, and have already had to send it to fisher once for a threshold knob problem, but was curious. Shouldnt I be able to set thres into the + range, even 1 or 2, without getting chatter? I'm finding the only way I can go past 0 is if my gain is set in the 30 to 40 range, and sometimes not even then. My fe is showing 1 or 2 bars in most places I go, gb bouncing from 34 to 68ish. Oregon doesnt have much of a summer so I really dont want to have to send it in again as the last time it took 3 weeks to get it back, but if its broken still I want the darn thing fixed.

Streak! · Aug 3, 2011

When you use the phaze lock..................does the Gb bounce like you describe? a spread of 24 to 68 is a lot. It should settle down to just a number or two. Its important you GB over a clean spot.....and that you release the phaze lock button WHILE your bobbing you coil........AFTER the numbers have settled down. If you release the button after you stopped bobbing. the Gb will not be correct. If you cant get a clean ground balance..... you wont have optimal performance.
Do you know if you have any external interference sources? Does the chatter occur when the coil is off the ground......but gets better with the coil on the ground while your sweeping? (Obvious Rf interference)
What kind of soil is it? one or two Fe304 bars isnt too bad.
There ARE a ton of soil sites that will give you fits though. Old shoolhouses with lots of coal ash is a good example.
Be sure you batteries are good. (test em).....and make sure your coil wire is well connected. Do you have the newer screw in connector, or the older plug in type? Streak!

Mezrein503 said:
hey guys, was just wondering if this might be a problem. I've had my F5 for about 2 months now, and have already had to send it to fisher once for a threshold knob problem, but was curious. Shouldnt I be able to set thres into the + range, even 1 or 2, without getting chatter? I'm finding the only way I can go past 0 is if my gain is set in the 30 to 40 range, and sometimes not even then. My fe is showing 1 or 2 bars in most places I go, gb bouncing from 34 to 68ish. Oregon doesnt have much of a summer so I really dont want to have to send it in again as the last time it took 3 weeks to get it back, but if its broken still I want the darn thing fixed.

Mezrein503 · Aug 3, 2011

Screw in type connector, bat's full charged and volt meter tested, ground balancing with phase lock is the same kind of spread, 24 to 50 or high / lower. Chatter occurs both in the air and sweeping when I get my thres past 0. I am going to try something tomorrow after noticing something today, going to turn my cell phone off. I know it can be a source of EMI, was shown just how bad that source is this morning. Was happily swinging away, talking with my fiance, lost cell connection which happens to me a lot, switched from 3g on my phone to standard edge, and while the switch was happening, my quiet, sitting idle detector went bonkers, then as quick as it started, it stopped. So tomorrow I'm going to go without my cell on, see what happens.

Bart@Big Boys Hobbies · Aug 3, 2011

Great post Streak!

Streak! · Aug 3, 2011

Cell phones have long been a major source of interference. My cell used to drive my Shadow X5 nuts. I dont seems to get any audible interference from my current cell with the F75...........but that doesnt mean there isnt some silent interference.
Your GB doesnt sound right. Do you have a different coil you can try? It SHOULD settle down to within a number or two, unless your over something funky. My moneys on a bad coil.
This might seem like an odd question, but is it worse when its real humid out? My origonal F5 would go nuts when it got humid out, and it was due to the mainboard being contaminated. (Greasy fingerprints or something). I disassembled it..........and cleaned it thoroughly with a good elec spray cleaner, and it got all better. It was tough getting the board clean without getting the spray on the display. I do NOT recommend that you try this, but its a possible source of trouble. Problem is the stick on face plate that makes it hard to get to the case screws. Better off letting the factory boys do it. :headbang:

I remember years ago I used to use an XLT at the beach, After a few months it would start to act up. I'd take it apart.....and all the IC's would have beards.

Black magnetic sand stuck to them. I'd remove the mainboard, rinse it under the sink, blow it off and let it air dry. Always worked 100% afterwards. Lots of thnigs that can cause problems....but it sounds to me like the coil is taking a crap.

Mezrein503 said:
Screw in type connector, bat's full charged and volt meter tested, ground balancing with phase lock is the same kind of spread, 24 to 50 or high / lower. Chatter occurs both in the air and sweeping when I get my thres past 0. I am going to try something tomorrow after noticing something today, going to turn my cell phone off. I know it can be a source of EMI, was shown just how bad that source is this morning. Was happily swinging away, talking with my fiance, lost cell connection which happens to me a lot, switched from 3g on my phone to standard edge, and while the switch was happening, my quiet, sitting idle detector went bonkers, then as quick as it started, it stopped. So tomorrow I'm going to go without my cell on, see what happens.

Mezrein503 · Aug 3, 2011

I wish I had another coil to try,

I've been fighting with myself on getting a 11" DD just to try something different. The ground out here has always seemed funky, to the point of in one patch I'm at 60's and in another I'm at 12. And in between is just that, inbetween 12 and 60. Its annoying to watch it trust me... I am going to be trying with the cell phone off to see if that helps any, and if I cant figure something out, as much as I HATE to do this because like I said, Oregon doesnt get much in the way of sun too often, I will send it back in to fisher. As far as humidity is concerned, I havent noticed a difference and it isnt as odd a question as you think. My pinpointer is a cheap stud finder from Harbor Freight, the 16 dollar one, and in the early morning before the sun comes out I can crank its sensitivity up real high, but as soon as the sun comes out and the humidity goes up because of the wet grass starting to dry, I have to turn my sens way down. At first it bugged the crap out of me, but I soon realized what was causing it and now its just normal.