bklein

I know I didn’t get piezos with the black rim - I’ll get some to try. Does the tegaderm intentionally space over the black rim of the piezo, leaving an air gap or is it pressed tight against the piezo? Is there leakage around the wires to the piezo? I took my headset off the AQ and drove it off my Wavetek function generator. Seems like flat response until something above 1600 Hz or so, then it gets louder. I just bought a piezo driver IC pcb from Adafruit but now think it would not be necessary for these disks we are trying. (It has a charge pump to output higher voltage than the supply)

Newark Electronics seems to be having a sale on Bulgin M8 stuff. Check it out but leave me something.

Ahhhh. It could be that the AQ has a piezo driver IC to drive the headset. If so, regular headsets probably won’t work well. Anyone know more?

I can make just about anything but without detailed guidelines I’d be just trying my luck. I have the parts (have to check if as recommended above) but have several quite different recommendations for mounting/sealing the piezos, plus I have samples of different diameters. Piezos are for waterproof headsets and I don’t hunt where I’d intentionally dunk them. So I would think that an off the shelf non-piezo set would likely be superior in response - but all the talk is about using piezos. I use my CTX with the wm10 and earbuds and I’m good. When I compared my AQ to a friend’s it seemed 1” less sensitive and both had identical looking headsets. Mine also was re-validated at the factory although I haven’t been able to validate that performance myself. That factory performance should have been tested with the headphones I sent in attached to it.

I was thinking someone else would experience the sound. I have limited time with the machine - I’m torn between trying different settings and just trying to find good targets. Just got it and have only been out 3 times with it - about 4-6 hrs each. I was running beach low conductors or deep, prospect or normal audio modes, 5 tones, default iron settings, probably discriminate but no added reject areas. I did not realize ground balance changes if I change modes. It was set to tracking but likely could be anything. (I was mainly in the wet or ankle deep water) Next trip I’ll play with ground balance. This mainly occurred at Laguna Main beach - same beach I had trouble with years ago with the EQ800. (We have a lengthy thread here somewhere). I’m liking this detector. Like the press and hold NC - finally see it really works. The sound is not prevalent - I’m just curious as it must have a meaning.

I have several headsets. Different transducers and connectors. No real clue as to what a “better” headset is except 700 Hz seems to be a sweet spot. I find the whole topic too poorly explained due to the language translation difficulties. The headset is supposedly waterproof and seems better than the typical yellow Koss set. A set not intended for water likely has a better frequency response. I haven’t heard of many recommendations mainly because there are only a handful of owners that post anything about the machine. I’ll get around to it and post results here.

I think they missed the boat on this detector by not having a generic mode that finds coins as well or better than other machines.

He has emphasized several times in his videos that some of the headphones that accompanied the detector are inferior. How do I tell? How would I modify them or what should I try/buy as a replacement? I couldn't understand what he was saying about them - if we need to look for a certain impedance or type of transducer.... Have any of you tried a bluetooth transmitter and a BT headset or earbuds? He seems to be saying that the impedance of the headset can harm the analog circuitry performance. So maybe a BT transmitter would have high input impedance and be superior?

I have one but never tried it. I thought too small for general hunting in beaches. Where should it be used and what is good about it?

It was happening throughout the day. I was running 5 tones. When it got busy I’d occasionally hear it - same sound as a button press. I could not seem to get it to repeat over a physical area. Maybe it sounds when tracking ground balance bumps a number?

I’m going along the beach and the detector is responding to the ground and it’s targets and occasionally makes a “took” sound - like I changed a manual setting, but I didn’t. Why does it make this sound? There must be some trigger in the firmware that causes it. I’m wondering what it is….

I wonder if TX power is fixed per each mode or if it may be variable depending on feedback from the RX signal.

You need a pinpointer pinpointer.

Awakening this thread. I managed to break the attach clip on the Minelab bungee thing. There is enough left on it to clip on to a ring or whatever but can easily come free. Doc’s qwipple has a similar clip. Both are unique in that they are easy to adjust. Wish they sold it separately. What search terms will get me to a good chest harness? I have the ML pro harness but it’s overkill for a Manticore or AQ…

I was on early development teams for internal and external drives. I was a pain in the butt to firmware guys as I had a reputation for finding issues that got by our standard testing. It wasn’t the tool it was human programming errors. On a detector I’d think they would have a boot routine that should remain separate from normal code. If limits of either area incorrect it could happen. I’d use heat, freeze spray, vibration of different types, and different supply voltages to find such problems. With detectors I’d say power supply quality is a major concern.

I think there has to be some kind of standard test given by the detector manufacturer for us to test our detectors and coils. I have had enough experiences myself with bad coils on my CTX and EQ800, poor depth on various surf pi’s, not as good depth on my AQ. Such tests must eliminate variables like mineralization as we can’t duplicate them. If a guy’s AQ has better depth than mine in air (and we are comparing side by side) I’d say there is a valid difference and it likely affects real world performance. I sent mine into Fisher and they said it detects a nickel in 16”. Well…. How do I duplicate this as I’m seeing/hearing 2” less. There are some air test videos of surf pi’s/DF’s where they must put a gold ring 2-3” from the coil to hear it. Oh jeez, your detector is out of calibration and you are missing targets.

Plastic-dip actually accentuates the cracks in the grey plastic insulation. Gave up on that and bought the 3x or 4x heatshrink. This works but is too thick to reuse the coil relief at the coil side. Might be a problem due to stiffness but otherwise works. Used the 3/16 on each litz and the 3/8” over both. Quality of the product is not consistent as far as shrinking and glue goes. Used the Wirefy brand, 50 feet spools. 50$ into it for hopefully 3+ coils.

I bought several coils over the years for my GP Extreme and just now am getting around to trying them. I discovered that some DD coils wouldn’t work - they result in alternating high-low tones without sensitivity to any targets. Is this indicating an issue in the coil or more of an incompatibility. The manual says some coils can act erratically - is this that?

We normally start at Ultraclean. Wife says to run cold but….

I watched one of Woody’s Detectormods videos and he says the wire is litz wire and cannot be replaced by regular stranded wire. You are likely correct that newer coils are a better way to go but maybe these would be useful if fixed. I’m thinking to try covering the length of the cable with a long piece of heatshrink tubing.

Oh crap. I get out my GPX coils and find 3 with bad cable insulation, the inner plastic insulation may be brittle too. They don’t have a shield so I’m wondering if some thick stranded AC power cord cable may be a sufficient replacement- any thoughts?

Actually it was a combination of both Volume Gain and Volume Limit that needed adjustment. Now there is more falsing that sometimes forces a recheck of an area. Some of those are a target right at the depth limit. After playing with these settings I am much more confident that when I don’t hear anything there really is nothing there. Unfortunately my beaches are still lacking targets even though some the high tides have some aggressive surges. They are coming at such fast speeds they can easily knock you over if you aren’t looking.

Many already think I’m a city employee with my CTX and Minelab harness.

I have been messaging with a guy in Brazil about these. The one for the dry sand is different than the one used in the waves. I’ll probably try making one and look like a fool using it.