Trix
Full Member
Would adding a10 foot patch cord between the coil and the detector head affect the readings or even work at all. Considering a pole mount to search underwater along a pond shoreline without wading.
Coil wire extension
- Thread starter Trix
- Start date
Rudy
Admin
If the detector is a VLF (you didn't specify), make sure that the cable has two shielded twisted pairs (one for the transmit and one fore the receive coil). The shield is connected to the existing cable shield. It would most likely work though there might be a slight shift in the target ID readings.
Trix
Full Member
Its for my Etrac. Full band spectrum. I havent ohmed the connections but more concerned about signal loss and waterproofing the connector that would be underwater.
woodbutcher
Forum Supporter
On eBay there is FBs coil extension cables,I've used them and they do work.
Rudy
Admin
I'd be more concerned with disturbing the induction balance, which is why I recommended two shielded twisted pairs. By having the transmit signal twisted pair in a separate shield from the shielded twisted pair for the receive coil, you are less likely to unbalance the coil
At the factory, the coils are normally "tweaked" to cancel out the noise effects from the transmit signal on the receive coil. After the coil is "nulled", it is induction balanced and is then sealed.
Trix
Full Member
Thanks Woodbutcher for the ebay tip. Wow, a 3 foot cable for about 60 bucks. I would need like 3 of them and there would be at least 3 connections to make waterproof. I have to assume 3 foot is perhaps the max on extension.
Thanks also to Rudy for your technical explanation.
Thanks also to Rudy for your technical explanation.
Trix
Full Member
I reached out to Minelabs US service and support asking if my 10 foot patch idea was even feasible. The reply I received was from Kellyco. Minelab forwarded my request asking if they could assist me. Kellyco responded with.......
"Detectors are tuned to the length of the stock coil, adding a 10 foot coil will affect the performance to a degree but we can make a cable for you. We do not normally stock that cable so I will have to get back to you with the cost once we find out the price of the cable."
When I get the projected cost I will update this post.
"Detectors are tuned to the length of the stock coil, adding a 10 foot coil will affect the performance to a degree but we can make a cable for you. We do not normally stock that cable so I will have to get back to you with the cost once we find out the price of the cable."
When I get the projected cost I will update this post.
Mud-puppy
Forum Supporter
Yeah, let us know! on a side note, there would indeed be a market for a 3' extension for an AtPro coil cable...
A lot of us beachsweepers running large coils would do a chest or hip mount if those cables were longer...A guy could cut and splice, been thinking of that myself, but I would have to find a wrecked coil and snip off the wire, cut and paste it onto my rig, get it right and tight....If there was a aftermarket extension available for $60? Yeah...they would sell...
Let us know what you find out Trix!
A lot of us beachsweepers running large coils would do a chest or hip mount if those cables were longer...A guy could cut and splice, been thinking of that myself, but I would have to find a wrecked coil and snip off the wire, cut and paste it onto my rig, get it right and tight....If there was a aftermarket extension available for $60? Yeah...they would sell...
Let us know what you find out Trix!
NectarDetector
Forum Supporter
- Joined
- Dec 7, 2013
- Messages
- 8,301
How do you plan to recover the target?
Trix
Full Member
Found this link today :
http://www.goldenroadmetaldetectors.com/coilteksite/FAQ.html#Q10
Specifically from Coiltek:
9. Can I get an extension lead for my coil?
Yes, we can make an extension lead for almost any coil. There are certain lengths which limit performance and for DD or Anti-Interference (A.I.) coils there is a link which needs to be removed from the coil plug for the extension cable to work efficiently. The diagram for the link remove modification will be supplied upon request when purchasing an extension cable. Maximum lengths suggested are:
• DD or A.I. CABLE – 4 metres (total length including existing cable length)
• MONO CABLE – 10 metres (total length including existing cable length)
NOTE: at the maximum suggested length there potentially can be some performance loss due to resistance in length of cable.
10. Does this improve its performance?
Yes, shortening a coil cable is fine however there will be a minimum distance required from the control box and headphones. If you are too close to these parts then there can potentially be an increase in noise through your detector. We really only notice performance issues when the coil cable is too long. The increased resistance of the length of cable affects the coils ability to transmit and receive within the frequency of the detector. The standard coil cable length is perfectly adequate for the detector to perform its magic and we have noticed no performance increase when shortening the cable below this length.
Hope this helps. Still waiting to hear how much of my clad they are gonna need.
http://www.goldenroadmetaldetectors.com/coilteksite/FAQ.html#Q10
Specifically from Coiltek:
9. Can I get an extension lead for my coil?
Yes, we can make an extension lead for almost any coil. There are certain lengths which limit performance and for DD or Anti-Interference (A.I.) coils there is a link which needs to be removed from the coil plug for the extension cable to work efficiently. The diagram for the link remove modification will be supplied upon request when purchasing an extension cable. Maximum lengths suggested are:
• DD or A.I. CABLE – 4 metres (total length including existing cable length)
• MONO CABLE – 10 metres (total length including existing cable length)
NOTE: at the maximum suggested length there potentially can be some performance loss due to resistance in length of cable.
10. Does this improve its performance?
Yes, shortening a coil cable is fine however there will be a minimum distance required from the control box and headphones. If you are too close to these parts then there can potentially be an increase in noise through your detector. We really only notice performance issues when the coil cable is too long. The increased resistance of the length of cable affects the coils ability to transmit and receive within the frequency of the detector. The standard coil cable length is perfectly adequate for the detector to perform its magic and we have noticed no performance increase when shortening the cable below this length.
Hope this helps. Still waiting to hear how much of my clad they are gonna need.
Trix
Full Member
Well right now its a little chilly, but it gets warmer in summer here in Texas. When I know where the target is I will be using my Garrett Carrot since it can handle the 5 foot depth.
Trix
Full Member
Still waiting on an estimate from Kellyco service regarding the patch cord cost. I'll update when it comes across.
Trix
Full Member
Repeated requests to Kellyco along with cc to Minelab in regards to an estimate for the coil cable extension have gone unacknowledged. Not what I expected from either company. I shall remember this when I need parts or service.
