Voodoo Main Discussion

[MartyJ1963]

Hi Alec,,,No, I only have 8.42v at the cathode of D6. And still only 0.76v on TP15. Thanks, Marty.

[lamoiz]

hi Marty, do you find your fault? can you make us a picture of your pcb? we might be able to see the problem if there is an error ...

[surfdetector]

Thanks George,,,Does that mean I don't have to worry about the voltage I checked on TP15? Am I able to move on? I just found a cable that may have 26 wires contained inside so 'll be able to measure and connect my LCD Cable if it has. Thanks, Marty.

Marty you need to be producing +5v before you can continue. Are you measuring ~+12v at the cathode side of D6?

[MartyJ1963]

Thanks George,,,Does that mean I don't have to worry about the voltage I checked on TP15? Am I able to move on? I just found a cable that may have 26 wires contained inside so 'll be able to measure and connect my LCD Cable if it has. Thanks, Marty.

[Qiaozhi]

I took some scope shots of my sync signal at TP9. Do these look ok? Thanks, Marty.

Yes, it's working.

[MartyJ1963]

I took some scope shots of my sync signal at TP9. Do these look ok? Thanks, Marty.

[MartyJ1963]

Thanks George and Alec,,,Sorry, yes, I meant to write -5v,,,I haven't checked the Sync pulse yet on TP9 (Too many house repairs keep surfacing during my build) but I will check that this evening then post these results. Great 2nd Voodoo video Alec! Regards, Marty.

[Qiaozhi]

Hiya George,,,I'm having a little problem with my build. I am getting +5v at TP14,,but I'm only getting 0.720v at TP15. I bought 2 x programmed PICs from Andy (Silverdog) and though I totally trust his programming skills I tried both PICs and still don't get the correct voltage at TP15. I re-programmed one of the PICS with the HEX you posted and still not getting the correct voltage at TP15. I have checked and double checked all the components I installed for correct placement and values,,I've checked for solder bridges and dry joints and I've totally cleaned my PCB. Could you tell me what I could try next please in the fault-finding? Should I try replacing the 79L05? The only different components I used were the FQT7N10LTF instead of the FQT7N10 which I couldn't find. Thanks, Regards, Marty.

There should be -5V at TP14, not +5V.
Assuming you meant to write -5V ... have you checked that there's a sync pulse from the PIC on TP9? This pulse clocks the LT1054 via Q5 and Q6. At the cathode of D6 there should be a voltage approaching +12V. This is then regulated by a 78L05 (U7) to provide +5V at TP15.
The FQT7N10LTF mosfets must be OK, otherwise you wouldn't have anything working.

[Qiaozhi]

I decided to go forward with the Voodoo project but will probably start from scratch with a coil since I plastic shells everywhere.
Question for George.. What kind of lead wire from the coil to the box? I have used two shielded pairs for some project, others I have used a high quality USB2 cable. The only difference I have seen with past projects has been that the coil will balance at a slightly different place.
Don.

Here are the cables I've been using in various projects:

1. URM43 single-core ( very close to RG58 )
2. E383E 2-core
3. Flexible 4-core (type unknown)

[surfdetector]

Hiya George,,,I'm having a little problem with my build. I am getting +5v at TP14,,but I'm only getting 0.720v at TP15. I bought 2 x programmed PICs from Andy (Silverdog) and though I totally trust his programming skills I tried both PICs and still don't get the correct voltage at TP15. I re-programmed one of the PICS with the HEX you posted and still not getting the correct voltage at TP15. I have checked and double checked all the components I installed for correct placement and values,,I've checked for solder bridges and dry joints and I've totally cleaned my PCB. Could you tell me what I could try next please in the fault-finding? Should I try replacing the 79L05? The only different components I used were the FQT7N10LTF instead of the FQT7N10 which I couldn't find. Thanks, Regards, Marty.

Marty are you getting the synch signal to the LT1054 from the PIC? I show it in my 2nd Youtube video.

[eclipse]

I have few boards for sale for Voodoo with shipping within the EU for 10E incl. shipping. Pay only if you get them for most forum members.
Boards are made in jlcpcb un-altered and in green color.
Free boards available for whoever bought defective board for TD3X from me as long as I have them in stock.

[Math]

Love the name, books ordered..
This project looks great i cant wait to get started!
Well done George and thanks

[MartyJ1963]

Hiya George,,,I'm having a little problem with my build. I am getting +5v at TP14,,but I'm only getting 0.720v at TP15. I bought 2 x programmed PICs from Andy (Silverdog) and though I totally trust his programming skills I tried both PICs and still don't get the correct voltage at TP15. I re-programmed one of the PICS with the HEX you posted and still not getting the correct voltage at TP15. I have checked and double checked all the components I installed for correct placement and values,,I've checked for solder bridges and dry joints and I've totally cleaned my PCB. Could you tell me what I could try next please in the fault-finding? Should I try replacing the 79L05? The only different components I used were the FQT7N10LTF instead of the FQT7N10 which I couldn't find. Thanks, Regards, Marty.

[dfbowers]

I decided to go forward with the Voodoo project but will probably start from scratch with a coil since I plastic shells everywhere.
Question for George.. What kind of lead wire from the coil to the box? I have used two shielded pairs for some project, others I have used a high quality USB2 cable. The only difference I have seen with past projects has been that the coil will balance at a slightly different place.
Don.

[lamoiz]

Hi lamoiz
Are you using silver plated copper wire with silicone insulation or plain copper with silicone insulation? Thanks for the information on your coil

yes, I think it is, because it is an old spool of thread that I have had in my workshop for a very long time, and there is no longer the informative label. silicone and silver color.