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View Full Version : Rx recommendations for SEF coils on the Whites V3



ramases
02-28-2010, 07:20 AM
Hi All

This is a question really aimed at existing V3 SEF coil users - especially the 1:blackeye:12. What sort of Rx recommendation do you get with the Probe feature? I have one coming (not V-rated) but have read elsewhere that the recommended Rx tends to be very low (in low single figures). Of course I know that Rx is not everything as SEFs have other advantages, but I would be interested to know what Rx you get from your SEF against the recommendation for the 10 DD or 6X10, assuming all other settings remain the same. Finally, now that some time has passed, how are folks doing with SEFs on the V3?

Cheers.

Colin.

CyberSage
02-28-2010, 03:39 PM
Hello Colin,

I have the 10x12 SEF coil. The probe function in multi frequency modes do not give accurate recommendation due to the skewed reading s from the 22.5 kHz frequency. At this point it is my coil of choice on the V3. The coil is not V rated (properly nulled) for the V3 however. You will need to allow for the 22.5 kHz frequency's unusually high VDI readings. On deep targets 8 to 11 inches you will notice the VDI wrapping clear around to the -95 to -93 range. If your ground VDI is reading in this range you will get some excessive noise. Moving the coil to fast on highly mineralized ground will also give the noisy condition. My average ground VDI is -80 to -85 and the mineralization of my soil is moderate in strength. I use the correlate mode exclusively with this coil and can easily hit a clad dime at 10 inches in the test garden. 2.5 khz and 7.5 kHz single frequency modes will work perfectly. Try the following program with the 10x12. This program is also posted in the V3 Thread with ongoing revisions.

Choose the Coin & Jewelry from the presets and make the following changes...

Discrimination
Accept (-95,-94,+40 to +95)
Reject (-93 to +39)

Notes: Set your accept range to include all + numbers (+1 to +95) if you want to include the gold range. Deep Nickels and larger gold items will still sound off with the default settings above. Accepting all + range targets will make things much noisier as well. Remember this program is primarily for hunting old deep coins.

Sensitivity
Rx Gain (9-10)
Discrimination (92-93)
All Metal (78)

Notes: Set your sensitivity to where your detector is stable. Do not sacrifice Discrimination sensitivity for Rx Gain. Keep the Discrimination sensitivity as high as possible. To much RX Gain will cause more problems with deep iron sounding like good targets.

Ground Tracking
Speed (15)

Frequency
Correlate (ON)
Span (43)
Wrap (-94)

Notes: I have now included -94 on the wrap and opened up the span setting to smooth out deep target responses.

Filter & Speed
Ground Filter (5Hz Band Pass)
Recovery Delay (115)

Audio
Tone ID (ON)
Modulation (OFF)

Set your Tone ID Mode to Custom and make the following changes...

-95 = 254
-94 = 253

Notes: This last adjustment on the audio will let a deep coin produce a nice rolling response as opposed to being sharp and cut off. Hot rocks and rusty nail tips remain sharp and cut off while coins sound smooth and roll in the decay of the generated tone. This really works well. Don't skip this last setting especially with concentric coils like the 950 and Super12. The 22.5kHz frequency is the reason for this last setting. It will tend to wrap on a good deep target. Something in the logic of the V3 will choose this frequency over the 7.5kHz. If your not accepting these values in the negative range your target will respond short and sharp sounding, or not elicit a response at all.

Swing that coil slow and in about 4 foot passes. Make a pass in both directions over the same ground before overlapping for your next swing. Keep that coil on or slightly off the surface. I am a scrubber and keep my coil right on the ground when hunting. This works well on grass and dirt. If there is small rocks then I lift the coil enough for clearance.

Bury some test targets keeping as much of the plug intact as possible. You will be amazed at the clearity and depth you can achive.

Keep Swing'in
Jack

ramases
02-28-2010, 05:45 PM
Hello Colin,

I have the 10x12 SEF coil. The probe function in multi frequency modes do not give accurate recommendation due to the skewed reading s from the 22.5 kHz frequency. At this point it is my coil of choice on the V3. The coil is not V rated (properly nulled) for the V3 however. You will need to allow for the 22.5 kHz frequency's unusually high VDI readings. On deep targets 8 to 11 inches you will notice the VDI wrapping clear around to the -95 to -93 range. If your ground VDI is reading in this range you will get some excessive noise. Moving the coil to fast on highly mineralized ground will also give the noisy condition. My average ground VDI is -80 to -85 and the mineralization of my soil is moderate in strength. I use the correlate mode exclusively with this coil and can easily hit a clad dime at 10 inches in the test garden. 2.5 khz and 7.5 kHz single frequency modes will work perfectly. Try the following program with the 10x12. This program is also posted in the V3 Thread with ongoing revisions.




This is VERY helpful - thanks very much for taking to time to answer this. I am in the UK so will have to adjust for accepted VDIs (I accept anything above 0) and have ground phase readings in the mid 90s so will need to work out which of your settings to change. Once again - thanks for your advice on this.

Activ8
02-28-2010, 05:48 PM
Yes this is really good. Colin and I have the V3, so any help with the SEF will be gratfully received

Dave

Slump-Shooter
03-03-2010, 07:13 AM
Jack, would these setting be largely applicable to the 4x8 SEF coil?

ramases
03-15-2010, 01:52 PM
This is VERY helpful - thanks very much for taking to time to answer this. I am in the UK so will have to adjust for accepted VDIs (I accept anything above 0) and have ground phase readings in the mid 90s so will need to work out which of your settings to change. Once again - thanks for your advice on this.


Well, have finally managed to get a few hours on a ploughed field and I now have an idea how to setup for a SEF. As expected, Rx is a lot lower in the 22.5KHz mode but in single frequency 7.5KHz it wasn't a lot higher (recommended 7 instead of 4). Interestingly, my 3-frequency mode (based on HI-PRO) also gets a recommendation of 4 - HOWEVER - I can run at quite a bit higher. Today on a much-hunted field I was able to double the Rx to 8 (Sens 85/70) and the SEF ran smooth as silk with 15% signal loss. The only downside is that running hot makes the SEF sensitive to bumping so I needed to raise the coil and inch or so. I finished up with a handful of buttons, a few musket balls and lead bits, three Georgian copper pennies and a hammered silver Commonwealth halfgroat (about 1650) - my first hammered of the year. All-in-all I'm very happy with the SEF. Signals are sharp and pinpointing is easy once you have the hang of it. I still need to make a depth assessment but so far, it is all good.

CyberSage
03-15-2010, 02:27 PM
Jack, would these setting be largely applicable to the 4x8 SEF coil?


Hey Shooter!

I am sorry I missed this post somehow. I would think that there would be little variance in any of the settings. Being a smaller coil you should e able to run it a little hotter as well. I know it works on the larger 12x15 SEF OK.

Keep Swing'in
Jack

CyberSage
03-15-2010, 02:28 PM
Thanks for the feedback on your experiences ramases!

ramases
03-23-2010, 06:42 AM
Well, things just get better .................. since my last post I have continued to net hammered silver coins with the V3 mated to the the SEF. I've had a further 5 silver coins including a couple of Edward I/III pennies, a tiny cut quarter penny (about 4mm across), an Elizabeth I halfgroat and a gorgeous Mary I groat of 1583 - a comparatively rare coin. All of these have come off well searched fields and much hunted areas so I have to say that I continue to grow in confidence with this combination of kit. I still run my modified HI PRO program with Rx a couple of notches above the recommendation. None of these finds have been particularly deep (up to 4 or 5 inches) but I am still getting the odd positive signal that is too deep to dig!!! All-in-all, I'm now confident that if I walk over any kind of decent target, the V3 will get it. thumbsup01

coinnut
03-23-2010, 12:06 PM
Sound like that V3 may be a great machine for that cut silver. If you are getting these targets from hunted fields, I would say it is working very well for you. Keep finding goods that nice and you may start a panic for the V3 in England lol

Big Red
04-14-2012, 06:47 PM
Jack, I know this is probably not the place to ask this question, it is about the V3i? But, here goes: I just bought a V3i in used, but new condition. Problem is, she sold the DD coil that came with it and is using an older 950 coil. I don't know if the coil is V rated or not, as the metal detector is just shipped. My question is, does the coil have to be V rated to work? If so, then I need a coil for general coin shooting, jewelry/probable prospecting use ? Is the DD coil that came with it, the better coil, or is there another White's coil better, (and which one?) or is the sef (and which one?) a better coil, in your opinion?
I need to order a new coil now, so I will have a functional coil, when my detector arrives in 7 days! Any help you can give me would be appreciated. I think you went from recommending the standard 10 DD coil, that comes with the V3i to the Sef coil ? (but, which coil?) Thanks, Big Red