EMI

[Rob (IL)]

There have been a few posts lately about noisy detectors. I hunted a postage sized tot lot today. I'm finding the playgrounds down here in Texas have not been producing much. Anyway I started up the V and tried to ground balance the V sounded like a motor boat. Most of my programs are based on the Hi Pro program. I tried frequency offset, no good. The same with RX and Sensitivity settings.

I changed to 7.5 single frequency, RX 3, and Sensitivity 80. I set the offset at +3 and it ran like a dream. It was quiet and no falsing. I then found approximately 100 coins. I guess no one else could hunt under the high tension wires that ran above the lot. I got clear coin signals all the way to the mat. The deepest coin (penny) was 6" and was clear and solid. I forgot, I was using the 6x10 coil. I was finding so many coins around the swings I didn't clip my DX1 between coins I just held it in my left hand.

To get closer to the posts I had to run the RX at 1 and was still getting good results. At Rx3 I was still picking up readings from the swings. I'd hold them out of the way and picked up a few more coins. Another tip, when you use your DX1 if you hold it near the cord you get the Max depth. As you slide your hold down on the coil it has the same effect as turning down the all metal. It gives you quick sensitivity adjustment. I don't think I could have hunted this site with my MXT. Rob

 

[KurtB]

Very good usable information. Thanks for the post. Glad to see your getting out. Here in Nebraska we are socked in with a good amount of snow.

Good luck

Kurt

 

[nw1886]

That is some real good info for EVERYONE!! Nice work Rob.

 

[lazy boy]

hey thank help out a lot

 

[slumpshooter]

Similar experience today in my back yard... I had interference as I have described here before at my home location. Drooping into analyze mode (trigger forward), I could again see that 22.5 Khz. had a huge sinusoidal sine-wave running through it, 7.5 and 2.5 Khz where almost straight lines (quite). I switched to single frequency, in this case 7.5Khz and Rx set at 4 and the V3 settled right down, Ground balance was easy, I was able to hunt quite well, down to about 7 or 8 " in clay soil, that is not bad. Plucked out 2 mercury dimes at 8" and a few pennies at almost 6" all in about 15 min. using a SEF 6x8 butterfly coil. Interesting part about this is, I had used my G 2500 over this same area more than a few times without having seen these coins.

 

[Larry (IL)]

Thanks for the inside scoop Rob, glad to hear that you are getting some hunting in.

 

[Aaron]

Thanks alot Rob, I'm hoping that info will help with all the problems I'm having around houses and buildings. I'm going to print this post off and keep it in my detector bag.
Best regards,
Aaron

 

[The Beep Goes On]

n/t

 

[jbow]

n/t

 

[Aurium]

Something else that might help with EMI, besides single frequency and reducing the RX settings would be a smaller coil. If the EMI is being transmitted via the coil circuitry, then a smaller coil would represent a smaller antenna area, and subsequently a lower susceptibility to transmitted
EMI sources. You'd probably still have to play with the detector frequency and RX gains but in really bad EMI area's this might be the solution when others don't work.