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PimentoUK

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  1. "We aren't even allowed to do that" Things are changing here on a daily basis, I was taking the opportunity before restrictions prevent it. I get to the location with a 5 minute cycle ride, which is permitted.
  2. You should recognise it, Simon. Pretty sure it's a UK bronze penny, the BRITT OMN in the inscription is clear enough. http://www.coins-of-the-uk.co.uk/pics/pen4.html I'm planning some social-distancing in the middle of a field myself tomorrow. Seems an ideal hobby for these difficult times.
  3. Perhaps "things are progressing" is intended to reassure us that things aren't going backwards ( because some problem has occurred etc ) and they haven't stagnated ( because of bureaucracy/legal/paperwork/Wu-Flu blahblah ).? I would like to ask Rick if he will again be the first recipient of a machine ( his own one?), or if he expects to now be just another customer, and get it much the same time as every other customer ?
  4. Good Job. Regarding: "once the battery dies, it's a throwaway job" That battery ( actually a single cell ) is easily replaced, by one the same size, or slightly smaller if need be. The size is marked on it, which is all you need, really. It tells you the physical dimensions, eg. this "492530" cell is 4.9mm x 25mm x 30mm. So a slightly undersize cell may be lower in capacity, giving a shorter run-time, but that's about all.
  5. Those British decimal pennies are worthless junk, and they are everywhere over here, much like the US and their 1 cents. You made me chuckle with your excitement about finding it. I remember finding a US Wheat 1 cent over here, and thinking "Cool!" , so I see the reasoning. It will date from 1971 ( a common date, being the first year ) to 1981 ( when New Penny changed to One Penny ) Did ML reply to your request about setting up the Eqx to behave like the Quish? I would be trying Beach mode, seeing as that's what the Quish puts out. You need to add a 'slogan' to your Signature, like: "..... and it was another silver!"
  6. Here's where I drew my info from. The English translation of the MD-Arena website page. Down towards the end of the readers comments [ie. angry Russians arguing ] are a scope screengrab, and some spectrum analysis. MD-Arena page I've attached the 'scope screen photo here, and also an Equinox Beach Mode waveform that Chiv posted on Geotech1. They match ( to my engineers eyes ) , what wasn't detailed was what mode the Vanquish was in at the time. It just may be different in some or other mode. So a little prudence is called for.
  7. This extremely thick grease is sometimes branded as 'Kilopoise' grease ( from the unit of viscosity ), one possible place to look is HiFi specialists, as it's used to damp down tone-arms on high-end turntables. Another possible source I have heard of is for radio-control vehicles. They use heavy grease in limited-slip differentials, one brand is Traxxas: traxxas grease These are just suggestions, I've never used any of these products on detector controls.
  8. After making some errors yesterday about what I believed were the Vanquish operating freqs, I have some proper facts today: Those Russians over on the MD-Arena website have been poking about on a Vanquish, and have posted a frequency spectrum of it's output, and a 'scope image of its waveform. And the surprise result is .... it's running like the Equinox Beach mode. The waveform is an exact match for the Beach mode scope capture's that Chiv made on Geotech1, and the frequency spectrum matches, too. So that is 7.8 kHz / 13 kHz / 18.2 kHz / 39 kHz Ratios are 3 : 5 : 7 : 15 How it then goes on to process these four is of course unknown .... it could be a straight 'copy' of the Eqx beach mode code, that would be the quickest simplest way of doing it - make use of the R&D that's already been carried out. If they only need to process two freqs for a given mode, they can, no need to change the transmitted output. I suppose this opens up the possibility of hacking Vanquish coils onto the Eqx ... though don't hold yer breath. I'll try and add some pics and further info later.
  9. "Here you go Pimento" Got to say, I've recently obtained a Deteknix P.I pinpointer in need of some minor repair. It's now working fine ... and my thoughts are turning to hacking it with a 4 inch coil, much like those scuba detectors. It can wait .. too many other daft projects: [ discriminating pinpointer with wireless headphone link ? ] [ two-box conversion for my F75 ? ] + more....
  10. 'Best coil size' depends on the type of machine: PI; single-freq VLF; multi-freq VLF. PI is easiest, a round mono coil can be mathematically analysed, and you can ( within limits ) assume it doesn't pick up much ground signal, to complicate matters. But anything with a complicated coil, like a DD ( or even an OO ) is beyond maths, and probably needs computer modelling ( like finite element analysis ) Then VLF's pick up ground signal, so plucking the small target signal out of the large ground signal becomes your next hurdle. Different coil sizes pick up different levels of ground signal . Multi-freq VLF's minimise ground signal effects, which ought to make things a bit easier. But probably not in practice....
  11. That's where there's a need for more Eqx coils. For specks like that, optimal coil size is probably 2 or 3 inches. ( I can't back that up, even a big discussion on Geotech1 didn't resolve 'best coil size' ) I want to make a 5 incher, pretty much like a First Texas one, and it's got to be easier than my number two project, an 18 incher ... but I don't know how you'd make a 2-3 inch one. Probably make it like a fat SunRay probe ? Plenty of space then for the electronics board. PVC water drainpipes come in tubes that could be suitable....
  12. For those of you pondering Nino's oscilloscope screengrabs: The lower display shows a spectrum analysis of the waveform transmitted. Horizontally, it's 10 kHz per division, and 20 kHz is dead centre. So the three peaks are in the 7-8 kHz area, the 18/19 kHz area, and 39kHz or so. When analysed more precisely, these are the 7.8 kHz, 18.2 kHz and 39 kHz frequencies. The ratios 3 : 7 : 15 mean that: (3 cycles of 7.8kHz) plus (7 cycles of 18.2 kHz) plus (15 cycles of 39 kHz) all add together simultaneously, to make one complex waveform that takes about 385 microsecs to repeat ( 2600 times per second ). The differences between the gold modes will be in the way these three freqs responses are interpreted. Eg. heavily biased to 39 kHz; a bit of 39k and a bit of 18.2k ? No-one knows.....
  13. EDIT: please ignore most of this "Vanquish Tech data" stuff ... turns out I've been misled by unverified sources ---------------- What the Vanquish spec says is : “VFLEX-IQ” with the choice of 7kHz or 18.75kHz single freq operation. Now 7k and 18.75k are pretty decent choices for single-freq operation, the 7k for milled coin hunting and general 'larger targets' , the 18.75k better for those 'nickel' targets, like gold finger rings, ancient European coins. But .... they are actually in a ratio of 3 : 8 , which is an easy to generate multi-freq waveform. Every 3 cycles of 7k, there are 8 cycles of 18.75k, so the whole waveform repeats every 437 microsecs ( ie. at 2344 times per second ). My guess is that these two freqs could be the only ones. It's running at 7k with the 18.75k for ground compensation, and at 18.75k with the 7k for compensation, and it's doing a 'best of' decision when interpreting these two 'readings' . And by not having any 39k / 40k operation, it puts much less constraints on the technicals of the product. Amplifiers need less bandwidth. Analogue-to-digital converters need only be half as fast. The DSP microprocessor only needs to do maths at half the rate. The coil needs less precise nulling. All these things make for a cheaper product. No doubt someone will stick a scope on one some time, then we'll find out. ------------------------- Update: "This was his response refuting another poster" ...yes, I am that 'other poster', so it does "look familiar". And that's where the difference of opinion about Gold mode originates. Chiv, and two others, see Gold mode as 7.8/18.2/39 , exactly as per Park/Field, but we would assume putting more emphasis on the 18.2k and 39k to favour the small nuggets. Carl is the only one to state the two freqs in his quoted post.
  14. "Equinox likely uses a combination of only two transmit signal frequencies to generate its multifrequency spectrum based on user measurements using spectrum analyzers documented in multiple posts on this site. The different mode spectrums for Park, Field, Beach, etc weighted towards high and low frequency spectra for Equinox are likely generated using different pairs of frequencies. If you read those threads, and the ones on Geotech1, you'll see the Eqx uses 3 freqs in most modes, and 4 in Beach Mode: 7.8kHz / (+Beach 13 kHz) / 18.2 kHz / 39kHz. Ratios are 3:(5):7:15. The weighting does vary. Park1/Field1 seem to be favouring the 7.8 kHz, Park2/Field2 favour the 18.2kHz. I'm not so sure about Gold modes ...opinions differ, and I personally have a 600 model, so it's not something I can check myself. Back to these aftermarket coils: There are technical merits to putting the pre-amp inside the coil. By relocating the ML pre-amp into a seperate box near the control-box, they are potentially losing some of those benefits. It's a simple solution, that works, but it's not ideal.
  15. "the fact of the matter is that they are both supporting Multi-IQ" Multi-IQ has no definition. They could make the Vanquish have completely different frequencies, and a different number of them, eg. just two, for example. They could issue a software update for the Equinox that gave it totally different frequencies, too. X-rays of the Vanquish here: forum thread And they are also on the MD-Arena website
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