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Underwater Antenna Experiment


parkgt

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4 hours ago, midalake said:

I have the antenna wire from coil to remote in the CF rod. For what it is worth the last part to the remote goes through my metal hand grip. 

I have not had signal issues. Will post a pic tomorrow. 

Yeah.  That shouldn't be an issue.  It's a wave guide so it's only radiating at the unshielded end of the coax (not along its length), so as long as there is no metal between the end of the waveguide and the receiver (remote or WS6) then there should be no issue even if it passes through metal.  The problem people were having was if they terminated the waveguide run inside the metal shaft where the metal shaft was blocking the rf radiating from the end of the waveguide to the receiver  If you do this, the radiating end of the coax needs to get close to the receiver or you can just terminate it in the non-metal CF lower shaft and it will work unless the waveguide tip gets submerged.  Remember, the signal is normally transmitted from the coil all the way to the remote without the need for a waveguide, so as long as the coil transmitter or waveguide tip is neither submerged in water nor enclosed in metal (e.g., the waveguide run is not terminated within the upper metal shaft), then the wireless signal to the remote should be unimpeded.

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15 minutes ago, NCtoad said:

What you posted above is what is confusing me about the remote losing it’s signal.  In that post Parkgt said that he tried running the co-ax cable all the way up the upper shaft but the signal wasn’t good.  What I’m not understanding is that if you run the co-ax cable just long enough so that it hangs out of the top of the lower shaft, some of that cable is still inside of the upper metal shaft.  If the metal shaft is causing interference, why doesn’t it cause interference when the co-ax end is is at the bottom half of the upper shaft?   In other words, if I run the co-ax so it just hangs out of the top of the lower shaft like Parkgt shows in his pic in the original post, the top of that cable will still be inside of the upper metal shaft.  If I made that cable longer so the end is near the top of the upper shaft, why would that make the signal worse?   Maybe I’m misunderstanding something.  Sorry if I am. 

See my explanation in the previous post above.

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Well, who said XP doesn't listen to us... They're putting out a new antenna! Skip to the 10 minute mark to see this.

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8 hours ago, Chase Goldman said:

See my explanation in the previous post above.

Thanks for the explanation Chase.  I had surmised that the co-ax radiated it’s signal from the unshielded end.  However, in the original post Parkgt’s photo shows the end of the cable sticking just past the end of the lower rod.  When he puts the lower rod in the upper metal, the end of that cable is then enclosed in the upper metal tube and as shown in the video it works fine.  Why is that?

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7 hours ago, CPT_GhostLight said:

They're putting out a new antenna! Skip to the 10 minute mark to see this.

LOL> It is black "so you don't have to worry about that discoloration." 

Well, that "discoloration" is the inside wire being eaten up by salt water. Now I cannot monitor it>>>great! 

Guess I have never been the out-of-sight, out of mind guy. 

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35 minutes ago, midalake said:

LOL> It is black "so you don't have to worry about that discoloration." 

Well, that "discoloration" is the inside wire being eaten up by salt water. Now I cannot monitor it>>>great! 

Guess I have never been the out-of-sight, out of mind guy. 

Exactly what I thought. Hopefully they fixed the water intrusion too.

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Well people have been complaining about the clear and super long antenna wire that has to be wrapped aound the outside of the shaft, so XP is making a black antenna wire that is much shorter and presumedly can be run inside the shaft. My take away is that they are listening and trying to to respond customers requests, and that's a good sign.

Not everybody wants the same things on their detectors and some have no problems with stock detectors, but if XP is going to be responsive to customers needs and wants, then that's a win. I'll take it, thanks XP!

It makes me wonder what else they may be working on. 😏

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6 hours ago, NCtoad said:

Thanks for the explanation Chase.  I had surmised that the co-ax radiated it’s signal from the unshielded end.  However, in the original post Parkgt’s photo shows the end of the cable sticking just past the end of the lower rod.  When he puts the lower rod in the upper metal, the end of that cable is then enclosed in the upper metal tube and as shown in the video it works fine.  Why is that?

Gotcha.  I just figured the the further you run it up the metal shaft, the more attenuation occurs, with the mid point probably being the worst.  The closer you are to either end of the upper less attenuation.  Couldn't say where in the upper Parkgt terminated the waveguide so I just assumed it was being attenuated by the upper shaft metal.  I'll have to run some tests myself because the "cut to suit" coax solution seems best.  It also looks like that's where XP is headed with their new antenna pack.

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3 hours ago, midalake said:

LOL> It is black "so you don't have to worry about that discoloration." 

Well, that "discoloration" is the inside wire being eaten up by salt water. Now I cannot monitor it>>>great! 

Guess I have never been the out-of-sight, out of mind guy. 

It's a non-issue as long as there is any continuous conductor present because neglible current is flowing and you just need continuity to the unshielded end.  I doubt it will corrode enough to break or that you can actually visually monitor the progression to know when it will fail.  The outer silver oxide corrosion layer may actually inhibit and slow down corrosion of the copper clad.  Anyway, you'll quickly ascertain when it does fail (loss of signal submerged)  so it makes sense to have a ready backup length of coax or spare OEM antenna assembly in standby.

Edited by Chase Goldman
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