To be clear, the question is about the Voovoo compared to the others.
Announcement
Collapse
No announcement yet.
Voodoo Main Discussion
Collapse
X
-
Originally posted by 6666 View PostCoil size, construction ?
Comment
-
Phatom - you're getting mixed up.
Carl Moreland is Carl-NC.
George Overton is Qiaozhi.
For those that don't know, "Qiaozhi" is a transliteration of "George" in Chinese Mandarin.
==========================================
I am sorry George and all the forum for the mess. I've been reviewing some issues in the ITMD and I wrote "Carl" when I should write "George"
Regards to all
Phantom
Comment
-
Originally posted by Elliot View Post8" outside actual coil diameter. Spiral Litz wire with Scotch 24 shielding. The Voodoo can be compared with these (one is industry standard - Nox 800 The other is discussed on Geotech and is a good example of what anyone can build at home.
Comment
-
Originally posted by MartyJ1963 View PostHi Qiaozhi,,,Sorry about more questions,,but could you tell us what voltage ratings the Electrolytic capacitors are please? And, if the Crystal and LCD has to be a specific sort as I have a bagful of 20.000mhz crystals and some LCD 16X2 (Blue backlight) left over from other builds,,if they will do? Thanks, Marty.
On page 25 there is some information about the type of crystal required by the PIC.
The LCD is the standard 16x2 character type. Note that the connector pins on the PCB are wired as 1 to 16, but be aware that some LCDs are wired as 16, 15, and 1-14. There are also others with two rows of 8 pins that require a negative voltage for the backlight. Do not use this latter type.
Comment
-
Originally posted by rickb View PostCan you give us an idea of real world performance compared to the best PI detectors on this forum?
Rick
Voodoo has two modes of operation - PI and Hybrid. In hybrid mode it is designed to find targets buried in areas with a lot of ferrous trash, such as UK farmland. These are places where a standard PI is not the first weapon of choice.
We all know of detectors that can demonstrate fantastic depth on a test target in areas with no trash. Youtube is littered with such demos. However, if you test the same detector is an area infested with ferrous trash the results are extremely disappointing.
The PI detectors in this forum are either non-motion or feature a self-adjusting threshold (SAT). If you've ever experimented with changing the speed of the SAT circuit, you will have noted that maximum depth is obtained when the SAT is very very slow. Whereas in practice the detector is much more usable if the SAT is active. If you read Chapter 7 it should be clear why Voodoo is a motion detector, and how it achieves good target separation. The Voodoo concept is about finding good targets in trashy conditions, not about maximum depth. On the other hand, depth measurements are quite respectable.
As they say ... "Horses for courses".Last edited by Qiaozhi; 10-23-2020, 11:15 AM.
Comment
-
Originally posted by MartyJ1963 View Post@Phantom,,,Has Silverdog received his order of boards yet? I visited the link for his shop but I can't see them available yet? Has he said he is supplying pre-programmed chips for the Voodoo or is this just a 'Maybe'? Thanks, Marty.
I haven't programmed a PIC yet, but as long as I can I'm happy to offer those too
Comment
-
@Qiaozhi,,Thanks for the info again. @Silverdog,,,Nice one Andy,,Looking forward to you annoucing when the boards arrive and the prices. It'll be handy to be able to buy a programmed chip too as it will save a lot of builders a lot of frustration who have trouble with programmng. Thanks and regards, Marty.
Comment
-
Originally posted by MartyJ1963 View Post@Qiaozhi,,Thanks for the info again. @Silverdog,,,Nice one Andy,,Looking forward to you annoucing when the boards arrive and the prices. It'll be handy to be able to buy a programmed chip too as it will save a lot of builders a lot of frustration who have trouble with programmng. Thanks and regards, Marty.
Comment
-
Originally posted by MartyJ1963 View PostCan anyone give a pat number or a link on where to buy the 20mhz 'Parallel' cut crystal please? All the items I've looked up don't say whether they are parallel cut or series cut so I dont know what to purchase. Thanks, regards, Marty.
Apparently any crystal that is listed with a load capacitance is a parallel resonant crystal.
This attached document has some useful information.Attached Files
Comment
-
Originally posted by MartyJ1963 View PostCan anyone give a pat number or a link on where to buy the 20mhz 'Parallel' cut crystal please? All the items I've looked up don't say whether they are parallel cut or series cut so I dont know what to purchase. Thanks, regards, Marty.
quartz hf ..
Comment
-
Originally posted by MartyJ1963 View PostCan anyone give a pat number or a link on where to buy the 20mhz 'Parallel' cut crystal please? All the items I've looked up don't say whether they are parallel cut or series cut so I dont know what to purchase. Thanks, regards, Marty.Originally posted by Qiaozhi View PostThe majority of crystals are parallel cut, so the chances are that the ones you have will work.
Apparently any crystal that is listed with a load capacitance is a parallel resonant crystal.
This attached document has some useful information.
https://www.digikey.com/en/products/...CC0A7AJiAugXyA
These are way more than accurate enough for anything we need.
Comment
-
Originally posted by waltr View PostI stopped using XTALs a long time ago with PICs. What I use are ceramic resonators with built in cap.
https://www.digikey.com/en/products/...CC0A7AJiAugXyA
These are way more than accurate enough for anything we need.
The price is certainly a good one.
Comment
Comment