Voodoo Main Discussion

[Qiaozhi]

OK thanks for update.
But it should be, for example i want book, but i dont want to pay 38USD for shipping, and i don't want to await too long for book.
With kindle i can have it instantly.
I understand that there are downsides of publishing ebook but there more advantages.
Best regards

There are no advantages to publishing an ebook ... except to those who want to rip-off the contents.

[surfdetector]

You where correct i disconnected the tx loop and thought it was the rx this it with the tx connected [ATTACH]54366[/ATTACH]

Post a clear picture of the transmit portion of your board with everything connected exactly as it was when you took this last picture. Coil, damping resistor etc...

[SilverSurfer17]

The yellow is the tx the red is the rx the only difference from this pic and how it was connected before was i had the jig connected at the pcb now its at the plug not enough room at the pcb and the wave still looks the same also with the rx coil connected

[surfdetector]

The yellow is the tx the red is the rx the only difference from this pic and how it was connected before was i had the jig connected at the pcb now its at the plug not enough room at the pcb [ATTACH]54370[/ATTACH] and the wave still looks the same also with the rx coil connected

I am unable to discern from that picture how you have your coil connected or the damping jig. You might be better off to connect a simple bundle coil to test the transmit.

[Qiaozhi]

I am unable to discern from that picture how you have your coil connected or the damping jig. You might be better off to connect a simple bundle coil to test the transmit.

Neither can I. But I did notice that R2 is not 3R3.
It should be orange-orange-black, not orange-orange-orange.

[SilverSurfer17]

Ok ill pull that out and get the right one

[SilverSurfer17]

No capacitor just the coil and the jig ?

[MartinB]

The yellow is the tx the red is the rx the only difference from this pic and how it was connected before was i had the jig connected at the pcb now its at the plug not enough room at the pcb [ATTACH]54370[/ATTACH] and the wave still looks the same also with the rx coil connected

From your photograph, it doesn't look like the red wire is connected. Could be mistaken of course.

[MartinB]

Hi Martin,

I will be able to determine the settings from the EEPROM contents.

The parameters are held in EEPROM bytes 1 to 18. Byte 0 will contain $AA, which tells Voodoo to read the EEPROM contents at startup. When the PIC is first programmed all the bytes are set to $FF. If Voodoo finds $FF in byte 0 at startup, it loads the EEPROM with default values and sets byte 0 to $AA.

You will be able to see the EEPROM contents using the PICkit. If you don't know how to read the EEPROM contents out of the PIC, then simply note them down and post the numbers here.

Hi George
finally up and running with the PICKit3
The attached image shows the contents of the EEPROM.

[surfdetector]

No capacitor just the coil and the jig ?

Post #277 has the steps in correct order for the build of the project.

[SilverSurfer17]

Ok i have the correct resistor ordered hopefully with that it will show the correct waveform and i can get past this roadblock ill work on these coils i guess until it gets here thanks again for the help Surf and George !

[SilverSurfer17]

I disconnected it to remove the rx circuit as a possible problem I'm following post 277 and I'm only concentrating on the pi circuit until i get it working correctly

[SilverSurfer17]

I desoldered the bucking coil and had just the tx loop and 1uf cap connected in that pic thinking that was a mono coil ill go check out how to make one so i can use it for testing after i get the resistor so i can eliminate the coil as a problem also until i figure out what im doing

[SilverSurfer17]

I see what you where talking about George with the inductance going up with tighter coils I thought you meant circumference not vertical and I didn?t take that into account with my coil and it going up after wrapping it I was trying to build it for coin shooting but I think it might be to high now so I might be redoing it Thanks Carol for the help you gave others for them to write that article with Tesla coils they use permeant forms the primary coil is 1/2 inch spaced and the secondary is on a tube those knitting forms look nice for winding all kinds of coils

[Qiaozhi]

Hi George
finally up and running with the PICKit3
The attached image shows the contents of the EEPROM.[ATTACH]54372[/ATTACH]

The settings that were different to the defaults were:
Pulse mode
PI threshold = 2
TX pulse width = 180us
Main sample delay = 49us
Number of PI readings to average = 40

The DISC settings are irrelevant as the detector is set to pulse mode.

I set my Voodoo detector to the same settings ... and it locked up.
After re-flashing the PIC I did some experimentation with the settings. It appears that there's some strange interaction between the TX pulse width and the main sample delay. This only occurs when the TX pulse width is set to 180us and the main sample delay is above 40us. All other combinations seem to be ok.

Now to figure out what's causing it .....