Voodoo Main Discussion

[MartinB]

Thanks for the offer, I ordered one from Tayda and it will be here in 7-60 days.

That is quite a broad estimate. Offer still stands if you need it.

[yukondave]

As I stated above, you might want to seriously consider doing the Arduino version of the Voodoo project. At least read through the pdf that describes the modification and you can do away with the PIC
Cheers

I did read through the PDF a few days ago but needed time to search through my parts bin. I came up with an Arduino and a 0.96" OLED display.



Is the adapter PCB available somewhere or do I need to upload the gerber to a service like PCBWay and buy 5 of them?

[Qiaozhi]

I did read through the PDF a few days ago but needed time to search through my parts bin. I came up with an Arduino and a 0.96" OLED display.

[ATTACH]56653[/ATTACH]

Is the adapter PCB available somewhere or do I need to upload the gerber to a service like PCBWay and buy 5 of them?

DIY Detectors don't have the Nano adapter on offer -> https://diydetector.co.uk/store/index.php
so you will need to upload the Gerbers.
JLCPCB will turn them round very quickly.

[yatahaze323]

I got some time to continue working on the detector and decided to measure the f75 coil and I'm getting,

TX: 430 uH

RX: 5.1 mH

Quite a bit different then George's coil was measured in the book.

I searched through the forum but I was having trouble finding the formula to calculate the parallel capacitor value for the RX to get the 10.5kHz frequency. Does anybody know it?

@surfdetector did you measure your f75 coil? If so what were your TX and RX values?

Thanks everyone!

[Qiaozhi]

I got some time to continue working on the detector and decided to measure the f75 coil and I'm getting,

TX: 430 uH

RX: 5.1 mH

Quite a bit different then George's coil was measured in the book.

I searched through the forum but I was having trouble finding the formula to calculate the parallel capacitor value for the RX to get the 10.5kHz frequency. Does anybody know it?

@surfdetector did you measure your f75 coil? If so what were your TX and RX values?

Thanks everyone!

Therefore:

[David_1]

hi all, I sort of vanished in 2012, Quite amazed to see many of the same names still active here
With pick and place so cheap now has anyone redrawn this as surface mount ? I favour JLcpcb at present !
Does anyone have pcbs in the UK ? can it even be made as Surface mount ???
Thanks all
David

[Carl-NC]

I got some time to continue working on the detector and decided to measure the f75 coil and I'm getting,

TX: 430 uH

RX: 5.1 mH

Those don't look right, the "official" values are 680uH and 6.8mH.

[David_1]

Hello can you see this

[MartinB]

Hello can you see this

Yes m8.

[David_1]

Yes m8.

thankyou I was thinking my post from the other night was only visible to me

[MartinB]

thankyou I was thinking my post from the other night was only visible to me

Hi David
PCB's are available from https://diydetector.co.uk
Not heard of anyone making a surface mount version, but I suppose you could always layout a pcb using Ki-cad or similar and then have the board made up by JLCPCB.
Sometimes you will not get an immediate response due to work load etc. May be the answer to your question was posted earlier in the discussion. Bit of a slog reading back over 64 pages, but worthwhile.

[yatahaze323]

Thanks George for the formula!

@Carl, I tested the coil again and I'm getting readings closer to the values that said. Getting TX: ~690uH RX:7.1mH, my connections must have been loose when I tested them before. Thanks!

[surfdetector]

I got some time to continue working on the detector and decided to measure the f75 coil and I'm getting,

@surfdetector did you measure your f75 coil? If so what were your TX and RX values?

Sorry, I just saw this. My values were very close to what George listed in the book.

[dfbowers]

I finally got around to finishing this project. It all went together pretty well. The only issue I ran into was that my oscillator would not run with the two 22pf caps installed. (C2 and C4). I tried 2 different crystals.. ECS-200-20-1X and one other from Digikey..once I clipped them out it runs fine. The PI section is very sensitive. I have to run the threshold around 10 or so.. The Hybrid mode is so-so.. Runs quiet even with the disc threshold set at 0 but sensitivity is adequate.. It runs best at all default settings.
For a coil, I built my own 10" concentric. 300uH TX and 6.8 mH RX. I will pot it later and do some field tests.
Here is a quick video of bench testing in both modes.
https://youtu.be/8dC6jkkSNBo
Don

[David_1]

Don ... something a miss with your YouTube settings or mine I subscribed but the bell Icon will not set, so I will not know if you release something new.. it says something about children settings ! lol sorry I can not explain any better !