gain

[markg]

My hunting buddy has had his V3i since early this year.
He has excelled in finding the quantity of silver over both my F75 and the black LTD. We have compared many targets and in most cases his machine will usually give a more clear, consistent tone over my LTD. His VDI seem to be more stable too. Well any way I have a question that no one here might have an answer for. He has three settings that he uses on the V3i. I think they are AC sensitivity, gain and boost or something very similar. Now here is my questions:
Is the transmission power of the F75 and LTD preset?
If not, then does the sensitivity setting control both the signal transmitted and also the receiving signal.

One thing I've noticed with my LTD is the fact that most of the deep coins 6-8" can still be heard with sensitivity settings below 30.

 

[markg]

-- moved topic --

 

[shooter]

Not sure about the other stuff, just don't know much about the other detector but had to lower my SEN to about 35 and still a solid hit at 6-8 inch. Black f75 LTD goes deep, some targets i'm afraid to dig in the park or school when there reading are high and CONFED is high but she showing 12-13 inches down. Heck of a big hole in the school yard.

 

[earthmansurfer]

Silver is detected best from around 4 - 7khz I heard. (It is a high conductor, like copper. My Omega does really well on these types of coins.). Maybe the lower of the three frequencies he is using is a part of the reason? But even more so, multiple frequencies do really well in mineralized soil. is the soil there mineralized (looking at the meter on your Fisher)? What does it GB at as well.


I never looked into the V3i, sounds interesting. What you your impressions regarding it (e.g. ease of use, overall depth, usability, balance, etc.)

Thanks

 

[markg]

My hunting buddy has had his V3i since early this year.
He has excelled in finding the quantity of silver over both my F75 and the black LTD. We have compared many targets and in most cases his machine will usually give a more clear, consistent tone over my LTD. His VDI seem to be more stable too. Well any way I have a question that no one here might have an answer for. He has three settings that he uses on the V3i. I think they are AC sensitivity, gain and boost or something very similar. Now here is my questions:
Is the transmission power of the F75 and LTD preset?
If not, then does the sensitivity setting control both the signal transmitted and also the receiving signal.

One thing I've noticed with my LTD is the fact that most of the deep coins 6-8" can still be heard with sensitivity settings below 30.

I guess no one can answer the question?
Is the transmission power of the F75 and LTD preset?

 

[txbluzman]

I don't know anything about the V3i but here is my 2 cents on this....as far as I know Sens controls the gain on the F75LTD. Higher the sens setting the higher the gain. I'm sure the F75LTD has a high and low limit / stop on gain and you control that with your sens setting. I planted a few items in my back yard and one was a silver dollar at 15 inches. I put the F75LTD in boost using the 11 inch coil and cranked up the sens (9 and it hit it every time with a clear signal. Planting coins isn't the same as one that has been sitting in the ground for years but that is the best we can do with testing.

Why would you run your sensitivity at 30? You should be running your sens as high as possible. I like mine set where the machine will chatter a little bit but not too much. No reason why you shouldn't be finding coins at ten inches with ease if you have the machine set up correctly.

I'm sure Mike Scott can answer your question or contact Fisher through their website. They have a Q&A email section.

 

[SteveP(NH)]

The transmit power is fixed and can't be changed by the end user. I'm not sure if boost changes that to a higher level than normal or not but in any case it is not adjustable by the end user.

the TX power on most detector is set to a sweet spot for the best signal to noise ratio. The main problem with boosting the transmit power is that the signal from minerals and salts in the ground is much stronger than the signal returned from a target. As you increase TX power past the sweet spot the signal to noise ratio gets worse.

Also the amount of battery power used up has to increase at a huge rate to get much deeper. For example use theory it would take 64 times as much TX power to get twice the depth but then your batteries would get used up in 10 minutes.

My best detecting buddy has a V3i but he found when he increased the TX power that he had to turn down his sensitivity in order to keep his detector stable so all he was doing was using his batteries faster since as he turned up the transmitter he had to turn down the receiver.

My F75 and his V3i seem pretty evenly matched as far as depth goes, we routinely call each other over if we find a deep, iffy signal to try and see if each others detectors can get a better lock on it. The one feature his machine has that I would like is that analyze screen, you can see how big the target is with that screen more precisely than I can tell using pinpoint mode and trying to determine where the signal from the target drops off at.

 

[markg]

My hunting buddies and I got out for a little target comparisons and,

We compared three different signals all of which were first found by the V3i. The first was a bouncer,
having my machine set to 4H tones it sounded awful so I switched to 2F
and got a better sounding tone, but the VDI indicated trash, but it
turned out to be a mercury dime at 7" deep. The next signal gave a more
consistent VDI and sounded better (still kind of scratchy) in both 2F and 4H tones and it turned out to be a common date
wheat penny at 6" deep. Now the last target was also analyzed by the
V3i, DFX and my LTD. This time the LTD gave a better pinpoint, but the
VDI was terrible and sounded kind of scratchy (would not repeat very often even in 2F), I thought it could be a coin or a nail but it sounded like trash and the DFX agreed, it turned out to be a 1879 Indian head (slightly on edge) about 7" deep.

Did find out that coal cinder waste was also dumped at this site but many years ago. Pumping the coil usually causes the FEO meter to max out. I'm sure that affects the whole game. Our next trip to this site will demand more detailed settings adjustments. The only thing I didn't change was the frequencies (because the machine was very stable) and the ground balance which I think might just be where I need to focus a lot of my attention on. Now mono tone gave the most consistent sound but I find it hard to hunt in real trashy areas in mono tone mode. One thing I noticed was that the depth readings on my LTD were about 3" off on the high side. Each target read either 10 or 11 inches deep, not sure why that is either.
As a final note, the V3i gave the best audio of all three machines. And yes the V3i was turned off each time we compared signals.