BigMerv
Jr. Member
- Jul 29, 2013
- 27
- 5
- Detector(s) used
- Radio Shack Discovery 3300 with 4", 8", and 10" coils. Time Ranger with 4", 8", 10", and F4 11" DD coils.
- Primary Interest:
- All Treasure Hunting
I have an early RadioShack Discovery 3300 that came with the standard 8" concentric coil. When I bought the machine I also purchased the 4" and 10" concentric coils. I've been really happy with it so far. In July of 2015 I purchased the Fisher F2/F4 (Part No. 11COIL-F4) DD coil with the push-on connector to use on the 3300. Shortly after receiving the coil, I had a hip injury that stopped me from detecting and this past April 22nd, I had a total hip replacement. I bought it for hunting the Mississippi Gulf Coast beaches.
Now that I can get up and down again, I'm getting back into detecting. I installed the coil for the first time last night and the 3300 began to immediately false. I've tried it indoors, outdoors, etc. With the DD coil mounted, it won't switch between All Metal, Discrimination, or Pin Point modes. The audio tones are random and never cease and the display dances with TID all over the place. The Sensitivity cannot be adjusted, etc. With the concentric coils mounted onto the detector, it's fine...performing like it always has. I've changed batteries, etc.
I'm fairly sure the coils is bad, but I did have two questions.
1.) Do you have to use the Fisher nylon mounting bolt and nut to mount the coil to the lower rod? I used the BH bolt and nut that originally came with the detector. I ordered 4 tall man rods and 3 sets of BH coil mounting hardware and pre-rigged all of my coils, but this one does have a different bolt and nut than the fisher model, or the other 3 that came with the tall man rods.
I'm going to unmount the coil from the lower rod this weekend, plug it into the control box and try it outside without the original BH mounting bolt and nut to see if they might be causing a problem. I also removed the coil cover to make sure there was no metal caught between the cover and the coil.
2.) Is there a way that I can check the coil myself? I have several VOM meters and could check pin-to-pin resistance, etc. to see if there's an open or shorted circuit. I have no idea what the pin-to-pin resistance values should be for a good coil, though.
I should have checked the coil as soon as I bought it, but was dealing with bigger problems. Since it's out of warranty, I'll have to eat the cost of the coil since it's been so long between the time I bought it and installed it. I doubt the factory would help with this. My story sounds incredulous, but it's true.
Lastly, has anyone tried the NEL coils on the 3300? I vascillated between the NEL and the Fisher DD, but decided to go with the Fisher since it was supposed to be directly compatible with the 3300. If I have to pay for a replacement coil, I might try the NEL this time.
Thanks!
Now that I can get up and down again, I'm getting back into detecting. I installed the coil for the first time last night and the 3300 began to immediately false. I've tried it indoors, outdoors, etc. With the DD coil mounted, it won't switch between All Metal, Discrimination, or Pin Point modes. The audio tones are random and never cease and the display dances with TID all over the place. The Sensitivity cannot be adjusted, etc. With the concentric coils mounted onto the detector, it's fine...performing like it always has. I've changed batteries, etc.
I'm fairly sure the coils is bad, but I did have two questions.
1.) Do you have to use the Fisher nylon mounting bolt and nut to mount the coil to the lower rod? I used the BH bolt and nut that originally came with the detector. I ordered 4 tall man rods and 3 sets of BH coil mounting hardware and pre-rigged all of my coils, but this one does have a different bolt and nut than the fisher model, or the other 3 that came with the tall man rods.
I'm going to unmount the coil from the lower rod this weekend, plug it into the control box and try it outside without the original BH mounting bolt and nut to see if they might be causing a problem. I also removed the coil cover to make sure there was no metal caught between the cover and the coil.
2.) Is there a way that I can check the coil myself? I have several VOM meters and could check pin-to-pin resistance, etc. to see if there's an open or shorted circuit. I have no idea what the pin-to-pin resistance values should be for a good coil, though.
I should have checked the coil as soon as I bought it, but was dealing with bigger problems. Since it's out of warranty, I'll have to eat the cost of the coil since it's been so long between the time I bought it and installed it. I doubt the factory would help with this. My story sounds incredulous, but it's true.
Lastly, has anyone tried the NEL coils on the 3300? I vascillated between the NEL and the Fisher DD, but decided to go with the Fisher since it was supposed to be directly compatible with the 3300. If I have to pay for a replacement coil, I might try the NEL this time.
Thanks!
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