Help with DFX Mixed Mode

[time4me]

When detecting with Mixed Mode turned on, what should I be listening for, and what should I be looking for on the display?

Also, is there a base program I should start from and then turn on Mixed Mode? The only other feature I usually change is turning VCO on.

I tried it out this evening at my in-laws mid 1800's farm house yard, which is chock-full of iron junk from square nails to shotgun shell ends, to you name it. There is so much noise going on, that I can't even begin to sort it out in my head.

Maybe a real trashy old farmhouse yard like this is not a good candidate for Mixed Mode?

Any help is greatly appreciated.

[djduk00]

Greetings and welcome I have also been trying Mixed Mode (MM) there is lots of info on the dfxonly.com forums might help you to read those posts.

[Sarge]

It's really hard to explain what to listen for. The all-metal channel sounds off on everything & the discriminate channel only sounds off on the VDIs you've selected to be accepted. An accepted targets will sound off in both channels at the same time. It's driven better men than me crazy!

What I've been doing lately is turn DC Phase On, run my DC Sens up to 40 or 50 throw my pinpoint switch forward to lock it in the On position & sweep slowly. When a target is indicated I check the DC Phase VDI at the upper right corner of the display & then turn the pinpoint switch off, resweep & see what the main VDI number is. It's called reverse discrimination.

dfxonly.com has lots of information on this subject including some user programs like dj said. Also Jeff Foster's "Digging Deeper With the DFX" explains it all.

It takes less time for me to type this & for you to read it than to actually do it.

Of course everyone knows I'm a bad typist & you're a slow reader!

[time4me]

Thanks for the tip Sarge! I'll try it.

Jim

[Eu_citzen]

May I ask you if you're experienced with the DFX?

This is a not-so-hot program I use when scouting, excellent when there is no need for 100% depth but more easy on the ears I think:
Target Volume 48 [User preference]
Audio Threshold 17 [User preference]
Tone (Audio Freq) 247 [Good targets get a higher pitch]
Audio Discrim ON
Silent Search OFF
Mixed Mode ON
A.C. Sensitivity 75 [SET FOR STABLE OPERATION]
D.C. Sensitivity 50 [SET FOR STABLE OPERATION]
Backlight OFF
Viewing Angle 25

Pro Options: Audio

Ratchet Pin-pointing OFF
S.A.T Speed 8
Tone I.D ON [Needs to be on for better iron ID, listen for good targets they are high pitched]
V.C.O ON
Modulation OFF

G.E.B /Trac

Autotrac ON
Trac View OFF
Autotrac Speed 8
Autotrac Offset +1
Trac Inhibit ON
Coarse G.E.B AUTO
Fine G.E.B AUTO

Descrim Edit

Accept: -95 to 0
Reject:+1 to +95 [This is indeed correct]
Block Edit AS EDIT
Learn Accept OFF
Learn Reject OFF
Recovery Speed 30 [Set higher for more trash, lower for little trash]
Bottlecap Reject 1
Hot Rock Reject 5 [If you've got problems with hot rocks turn it up]
Sweep Speed 1
Ground Filtering 3-4 [Depends on trash and mineralization]

Display

Visual Disc OFF
Icons OFF
V.D.I Sensitivity 85 [Set higher if you want more depth, trade off is stability; use signagraph]
D.C Phase ON
Graph Averaging ON
Graph Accumulating ON
Fade Rate 7

Single Transmit Receive

Preamp Gain 3 [SET FOR STABLE OPERATION]
2 Frequency (best data) ON [If problematic to get stable try correlate]
2 Frequency (correlate) OFF
V.D.I Normalized ON
1 Frequency (3 khz) OFF
1 Frequency (15 khz) OFF

[Eu_citzen]

Ok here's a quite hot program I'm experimenting with, if you're "quite" new don't try this on yet though get used to other programs first.

Target Volume 48 [User preference]
Audio Threshold 18 [User preference]
Tone (Audio Freq) 238
Audio Discrim ON
Silent Search OFF
Mixed Mode ON
A.C. Sensitivity 76 [SET FOR STABLE OPERATION]
D.C. Sensitivity 50 [SET FOR STABLE OPERATION]
Backlight OFF
Viewing Angle 25

Pro Options: Audio

Ratchet Pin-pointing ON
S.A.T Speed 6
Tone I.D ON
V.C.O OFF [Use if you want, I find it annoying when using it together with Tone ID]
Modulation OFF

G.E.B /Trac

Autotrac ON
Trac View OFF
Autotrac Speed 8
Autotrac Offset +1
Trac Inhibit ON
Coarse G.E.B AUTO
Fine G.E.B AUTO

Descrim Edit

Accept: -40 to +95
Reject: -95 to -41
Block Edit AS EDIT
Learn Accept OFF
Learn Reject OFF
Recovery Speed 20 [Set higher for more trash or lower for more depth]
Bottlecap Reject 1
Hot Rock Reject 1 [Adjust as necessary]
Sweep Speed 5
Ground Filtering 3 [Depends on trash and mineralization]

Display

Visual Disc ON
Icons OFF
V.D.I Sensitivity 85 (can be set higher, trade off is still stability of the VDI's)
D.C Phase ON
Graph Averaging ON
Graph Accumulating ON
Fade Rate 7

Single Transmit Receive

Preamp Gain 3-4 [SET FOR STABLE OPERATION]
2 Frequency (best data) ON
2 Frequency (correlate) OFF [in iron use correlate and/or in much trash]
V.D.I Normalized ON
1 Frequency (3 khz) OFF
1 Frequency (15 khz) OFF

[Sarge]

Eu_citizen,

Your 2nd program is almost identical to mine with the exception of AC Sens to 80 (if I can get away with it) DC Sens 55, Sat speed at 8 or whereever I can get a steady threshold, & Modulation Off. I find myself using the same AC & DC Sens that you use about 50% of the time with PAG at 4.

I still lean toward all-metal using Reverse Disc. techniques.

I tried both at a park yesterday in a big empty field. I found some copper pennies at about 6" from the '50s & '60s & 2 wheats, a '37 & a '41 at 8". The ground was almost too hard to dig that deep.

[Eu_citzen]

Hello Sarge.

I can't get it any higher in my area, the AC and DC sens that is. Neither the PAG can be put higher except if I use Correlate that might help.

With my second program I've hit a coin at about 8" with no bigger problem.
Here's the specifications of the coin:

Swedish 5 Öre 1972
Diameter: 18 mm
Weight: 1.44 grams
Alloy: Copper

Regards,
Eu

[Schrecky]

This post may be helpful: http://www.dfxonly.com/forum/viewtopic.php?t=5381