RELIC HAWK

[KingJL]

Hi JL,
yes, you are absolutely right about phase. I've changed number of turns to get 5KHz before making such tests... now I read 4.973 Khz on oscillator.

Wire is 0.56mm resistance around 2.5ohm, turns I'm employing at TX are 45.

PS: can you post the .asc file of your simulation ? I'd like to watch at it...

Kind regards,
Max

Here is zip containing the asc file and screenshots of run with GB set at 10K and 0.1 ohm.

Regards,
J. L. King

[Fred]

Now i understand!

[nakky]

Hi Max,I read in the manual that the manual gb trimpot must by 10 turns.Grt Nakky.

[eclipse]

Max don't forget that this is musketeer, and RH should have some differences (i think), but overall is no less than 95.99 % equal schematic. Probably the bigger coil gives extra boost in depth and also the musket misses the LSM switch.
I sold the device, i would be more helpful if i had it but ...
There was a bidding on ML RH on ebay few days ago but i didnt win cos i had a vacation and was away from the internet
the bid was too low.

[RufusGartz]

Relic Hawk Manual

Relic Hawk Manual (English) (2822 KB):

http://rapidshare.com/files/127811179/RelicHawkManualEng.pdf.html

One of the few manuals not available on Minelab's website. Finally got around to scanning it in. No, I don't have a Relic Hawk Metal Detector but I do have the manual.

Rufus

[Max]

Hi,
I found now the 91K... so it's right in schematic we have.

But why there are 910K resistors then ??? Different from our schematic.

I found 2 of 910K till now, we haven't in schematic.

Kind regards,
Max

[Max]

Hi,
I took a look at some pictures kindly provided by eclipse ... still cannot figure out about "f" stuff... cause difficault to follow but I see interesting stuff.

...all double op amp ic are 27M7, that would be nice having too there

All interesting, I'll take a look for other details...

Kind regards,
Max

[eclipse]

Actually its not a bad idea to post them all uncompressed, high quality and nice... i don't think i can duplicate it my own, but together we could.
My idea is if we reverse musketeer pcb, we can recover the electricial schematic and from there to upgrade it to relic hawk (the differences should be minimalistic)

[eclipse]

Check this out, I'm making new thread for XS PCB, stand by... to compress and upload

[Max]

The "f" connection persists in the coinseeker like RH schematic, (looking at 1.8 version). I have high quality fotos of musketeer PCB,
before i sell it made bunch of 7Mega pix fotos, if you think they can be usefull i will post them here.

Hi,
probably circuit is really close to RH... if you can, post them, could give some help solving the mistery of "f" connection.

If too large use rapishare.

Kind regards,
Max

[eclipse]

The "f" connection persists in the coinseeker like RH schematic, (looking at 1.8 version). I have high quality fotos of musketeer PCB,
before i sell it made bunch of 7Mega pix fotos, if you think they can be usefull i will post them here.

[Max]

Question: Can I use normal inductor (bobine with 2 pins)
with 15mH inductance instead of the transformer?

I've made this way... used a neosid inductor and rewound for 15mH exact.... and works good.

Kind regards,
Max

[Max]

Max,
What is your oscillator frequency? You said it was low on the coil you made. The frequency has a great effect on the GB control. Example: at 5kHz the range of the phase shift for the GB control is 82 - 99 degrees (-8 to 9 around the 90 degree null); at 4.6K it is 89 - 105. If your frequency is below 4.5kHz you are above 90 degrees minimum setting and never be able to get below the 90 degree null point.

Before you determine that GB not working, I would get the frequency very close to the design target of 5kHz.



Regards,
J. L. King

Hi JL,
yes, you are absolutely right about phase. I've changed number of turns to get 5KHz before making such tests... now I read 4.973 Khz on oscillator.

Wire is 0.56mm resistance around 2.5ohm, turns I'm employing at TX are 45.

PS: can you post the .asc file of your simulation ? I'd like to watch at it...

Kind regards,
Max

[Max]

Hi Max,

Is this result with the modified "F" point and did you try to configure the coil differently, to adjust shifting ?
regards!
Fred.

Hi,
the device is really critical related to coil phase shifts... you slightly modify it and all change...including lot of randomic beeps from time to time.

These results are from moving "f" to the geb channel control.

I see device is not so critical about nulled voltage... could be also some volts at output of preamp... and it still work (on the bench) like when there's 100mV there but I don't know about exact phase shift required.

I found that in disc mode I can null ferrite and iron stuff about totally, if I exclude some randomic effect from time to time... the behaviour is consistent in disc mode... but when I switch back in all-metal it sounds with ferrite rods and iron ...

Now iron is ok in all-metal... but not ferrite ! So I think there's more to understand about it... probably something that works in disc mode stop working in all metal... cause all-metal channel is much more related to geb little untuning ... so far I checked for the best nulling but nothing till now.

Probably the accurancy required to gain a good null is under 1°.

Kind regards,
Max

[Max]

I think there are still errors in version 1.8, MAX. According to me (and the schematic there) the generator should not work... Do you work on version newer than 1.8? Also there is written 26бр. which on bulgarian means 26 pcs x 100 nF - 2 capacitors on each IC? OMG sounds crazy, could it be

Hi,
probably it's so... there is some other mistake in schematic, I think could be too.

For "generator" you mean maybe the oscillator ? It works with 0.56mm wire TX coil now, just use BC337 and BC327 in it, high hfe on all. The voltage is a little bit more than 16Vpp... maybe 16.2 or 16.3Vpp on 0.56mm coil I didn't read it carefully cause I expected 16Vpp there and so it's well enough for me.

I'm working on version 1.8 of schematic plus the correction at trimpot I explained before and the "f" line of above, just these 2 stuff are not in schematic, I'm awaiting for some confirmation before I put them in schematic too... new revision, cause I cannot be sure at now they are correct 100%, though this way circuit make more sense to me.

I think 266 is actually something 26@100nf meaning "26 at value 100nf"... maybe it's drawn too simplified... but it's clear the capacitors are decoupling on every ic, 13ic , 2 per ic... so 26.

Kind regards,
Max