BH Discovery 1100, 2200 & 3300 Calibation???

M

MRhoades

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May 29, 2006

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7

• Jul 23, 2006

• #1

Does any mmbers of this forum have any experience with having to have their BH metal detector "recalibrated" to increase its accuracy or as part of a repair?

The reason for the question was that I posted a lengthy note on a BH Dscovery 1100 where I replaced a failed speaker. In the repair process I found 3 wires that had to be re-soldered to the main PCB (poor soldering) that connect to the MD search coil. My first thought would be that I could have altered the circuit impedance  from what existed at assembly. If there is a factory alignment / calibration procedure, then I may have just reduced the MD's accuracy to some degree. Any comments?


Thanks in advance.

-Mike

 

WThesing

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Jan 10, 2006

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Montgomery County, Pa

• Jul 24, 2006

• #2

I am not being critical, but I don't think those detectors are that sophisticated in their design. Calibration would be in the coil. The circutry is "matched" to the coil.

 

B

Brian

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Jan 13, 2006

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550

• Jul 26, 2006

• #3

I see where your coming from but if the machine worked at all then making a better job of the joints should not have any effect BUT I do know that Bounty Hunter suggest a re calibration if your buying a new machine with two or three coils. Thing is I'm not certain its a true re calibration but rather a swopping around of several coils of each size to find two or three that are a good match.

 

M

MRhoades

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• Jul 27, 2006

• #4

Thanks for your input.

I asked because I noticed a variable resistor inside the MD on the main PCB. Without a lengthy inspection of the PCB etc, I thought it might be a frequency adjustment. So...Like any other intrigued Electronics Engineer, I wondered if I might be able to improve the MD's selectivity.

 

M

MRhoades

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7

• Jul 29, 2006

• #5

FYI...the BH Discovery 1100 is a Pulse Induction (PI) design. The BH D1100 does not have a pinpoint mode (what can one xpect for such as low cost). However, frm what I researched, the PI design is a very sound design fro a good "basic" metal detector.

In PI MD design the "discriminator" modes are acheived by increasing or decreasing the default sample delay. I will likely open the detector up in the future and create some schematics at some point (always wanting to build a "better" mouse trap). If I do, I will post the info in this forum for those that are interested.

-Mike

 

T

TonyinCT

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Jan 11, 2006

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1,899

• Jul 30, 2006

• #6

Where did you find out that this was a PI ? I see no indication in the manual and from all indications of its operation it appears to be a VLF.

 

B

Brian

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550

• Jul 31, 2006

• #7

The Bounty Hunter is a normal motion discriminator with three tones. There's some talk that Bounty Hunter might bring out a P.I. in the future but there's not one in the range at the moment, in fact I don't think they ever produced a P.I.

 

M

MRhoades

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May 29, 2006

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7

• Apr 11, 2007

• #8

Sorry I have not answered you back...I put my metal detector up for the winter and have not even looked at it.

Having read the previous replies to my original posts it seems likely that I made a mistake in calling it a PI design.

I will eventually get around to taking it apart again and taking measurements with my OScope and find out.

At any rate I'll post pictures to the forum when I do so.

Thanks guys.

Mike