New guy with a question about radio interference

Shiva6150

Tenderfoot
Aug 31, 2015
7
1
Carson City, NV
Detector(s) used
Gerrett ultra GTA-350 - Was OK.
Radio shack POS... Never again.
Tesoro Lobo ST... Best of the best!
Harbor Freight 9 funtion - excellent disc.
Fisher 1265X - current daily driver, loves silver, HOT!
Primary Interest:
Metal Detecting
Hello, I'm new here, Have done some metal detecting over the years, not a lot, but enough to know how it works. I was wondering about radio interference to my MD, I am planning to search a local beach where a lot of people go but there may be a potential RFI problem at this location. About 500 - 1000ft away is a longwave NDB for the local airport at about 250khz frequency, can this cause my detector to malfunction or give false signals? I have never searched this area before and probably wont even bother if that tx is going to be a problem. My MD is a harbor freight 9 funtion VLF. The transmitter sends a repeating morse code signal about once every 10 seconds @ 50W output power. Is that enough to overload my MD or is the frequency high enough to not be a concern since the tx is longwave and the MD is VLF?

Thanks for any advice and I look forward to sharing some of my finds since I just found this forum today and just got a new MD after being out of the hobby for several years.
 

Upvote 0

Tnmountains

Super Moderator
Staff member
Jan 27, 2009
18,714
11,699
South East Tennessee on Ga, Ala line
🥇 Banner finds
1
Detector(s) used
Tesoro Conquistador freq shift
Fisher F75
Garrett AT-Pro
Garet carrot
Neodymium magnets
5' Probe
Primary Interest:
All Treasure Hunting
Welcome to T-net. I have one thats VLF and it has a frequency shift. I say that you should at least try the area and if it shuts you down you may mark it off as a learning experience. I think we all have hit areas that it worked for some and not for others.
Welcome aboard.
 

OP
OP
S

Shiva6150

Tenderfoot
Aug 31, 2015
7
1
Carson City, NV
Detector(s) used
Gerrett ultra GTA-350 - Was OK.
Radio shack POS... Never again.
Tesoro Lobo ST... Best of the best!
Harbor Freight 9 funtion - excellent disc.
Fisher 1265X - current daily driver, loves silver, HOT!
Primary Interest:
Metal Detecting
I will try that beach, I have wanted to search it for a long time because its a popular swim spot and hang out spot in the summer. Hopefully that transmitter wont shut me down, but if it does I have other places I can look that are rf free. There is a very old derelict building down there too that's haunted.. I had an experience there once with that ghost and all I can say is it didn't like me or my friend, we ran like hell out of there so fast we made a rocket look like a snail and broke some bearings on my bike. I haven't been there since(about 5 years). I will never go there again at night. But daytime is doable, uncomfortable but doable, maybe ill find what that ghost doesn't want anybody to find. LOL. I just might take some ghost hunting gear with me too. This could be interesting.
 

Ammietuar

Jr. Member
Sep 18, 2005
88
9
Suffolk UK
Detector(s) used
MXT/PI Pro/Garrett GS
It has been my experience that any metal detector will pick up interference from all sorts of things that a lot of people wouldn't expect: power lines; cell phones; am/fm radios; door/lights motion detectors; other metal detectors; planes flying overhead; people with change in their pockets; etc. If you think about it, it makes perfect sense, you are essentially using a device whose intent is to sense an electric or conductive field and relay that information to the user. Some areas are bathed in more of this interference than others, which could often be a good thing because no one else can look there easily either! My advice would be to start with high sensitivity and slowly lower it until you are not getting the false signals. A very slight raise in the discrimination can allow you to run higher sensitivity, but there is the obvious trade off. Good luck!
 

jeff of pa

Super Moderator
Staff member
Dec 19, 2003
85,775
59,570
🥇 Banner finds
1
🏆 Honorable Mentions:
1
Primary Interest:
All Treasure Hunting
only interference I've ever had was on my Explorer SE Pro
and I'm pretty Sure it's Aliens .

it will usually drive my Detector crazy for a few Minutes till I walk to another area .
then it will all of a sudden stop
and Run smooth again.
when I go back to the Problem area "No more Tears" all is good again.
 

OP
OP
S

Shiva6150

Tenderfoot
Aug 31, 2015
7
1
Carson City, NV
Detector(s) used
Gerrett ultra GTA-350 - Was OK.
Radio shack POS... Never again.
Tesoro Lobo ST... Best of the best!
Harbor Freight 9 funtion - excellent disc.
Fisher 1265X - current daily driver, loves silver, HOT!
Primary Interest:
Metal Detecting
I will check the site as soon as I have time, been busy with job searching. I know a lot of people have lost things there over the years, including me. I have never seen a MD at work there so wonder if that TX is why, wont know until I try. Its definitely worth it.
 

OP
OP
S

Shiva6150

Tenderfoot
Aug 31, 2015
7
1
Carson City, NV
Detector(s) used
Gerrett ultra GTA-350 - Was OK.
Radio shack POS... Never again.
Tesoro Lobo ST... Best of the best!
Harbor Freight 9 funtion - excellent disc.
Fisher 1265X - current daily driver, loves silver, HOT!
Primary Interest:
Metal Detecting
Well, I went to that beach and everything went well, my MD was working perfectly. No interference at all. Found a penny by the water about 4" deep and the tiniest brass knuckles I ever seen. You just never know what your gonna dig. Its worth a few more trips. At one point I was less than 200ft from the radio TX, that's where I found the brass knuckles about 5" deep.
IMG_20150901_153610:nopm:.jpg
I actually think that's some kind of alloy in the shape of brass knuckles.
 

Last edited:

Top Member Reactions

Users who are viewing this thread

Top