First of all, thank you for this valuable feedback!!
My 2 cents on the 10v regulated supply.
If these circuits are run on 12v battery power, like an auto, the variation on the supply will vary due to temperature, charge state, regulator, RPM, other electrical loads like headlights, etc. Plus the electrical noise could cause missoperation. The timing circuits and the PLL are all sensitive to these voltage changes. Stan planned to use this in the dunebuggy so he isolated the circuits. If you are building a bench unit that runs on a regulated 12v supply connecting the 10v circuits to the 12v will be OK but, realize that the VIC transformer primary could cause you trouble if on the same supply. Another note, the frequency range of the PLL is partly based on the supply voltage, some component values like the resistor on pin 12 may need to be changed.
PDF schematic on first post.
Be careful that all the 10v points are brought to the same voltage. I see that the feedback opamp is on the 12v supply and feeding the PLL running on 5v. Q8 output (12v) connected to U4C input running on 5v.
There is a missing capacitor from U8B pins 5 & 6 to ground. Should not be tried directly to ground.
I see you placed the 220 ohm resistor in series with the primary coil. This will limit the primary coil current to less that 50ma. I think that Stan and the KISS methode would not have used a TIP120 transistor and all the driver tranistors if the current was that low.
You guys are doing a great job. I'm still tring to come up to speed with all of the new data sence I was last working on Stans' process about 5 yrs. ago.
- I think that you are right in your assumption that when connecting the vic to the electrical system of a car the circuits need to be on 10V instead of 12V because overall battery load will not assure a stable 12V. In the first version of the schematic there was only a 5V regulator, i also realized that 12V car battery output is not stable enough to drive the logic circuits, so a 12V voltage regulator is already present, i am not sure yet if i adapt the vic to 12V where needed or will add the 10V regulator and change the connections. Currently i am on the first path.
- I also looked into the 4046 datasheet a bit more, ... i had mixed up a 74LV4046 and CD4046, the latter is used on the vic, the first is a low voltage part, need to change that on my test board but for the schematic, other than the supply voltage, there is no difference in pin layout. That brings me to the next two things, the center frequency(fo) and min/max frequency(fmin/fmax) of the 4046. From the datasheet it shows that they are slightly voltage dependend but not that much, also since the values need to be adjusted with the potmeter. With C1=0.1u R1=0.56k-50.56k ohms and R2=100k i get the following:
fo = ± 500Hz - 10KHz (adjustable with 50K potmeter)
fmin = ± 300Hz
fmax = ± 700Hz - 18KHz (changes with the value of R1 potmeter)
All should be within the required range for the resonance frequency in the order of 1 - 10KHz.
- You are right about the missing cap in the pll lock circuit. I missed that one from the datasheet and will add a 6.8nF cap to ground on pin 5 and 6.
- I had not thought about the cell driver part in the way you state it and i think you are right about that. Why using a power transistor when current is restricted to 50mA. I will change that back to the parallel resitor. The cell driver circuit has to be changed anyway, ... it is not working as expected. One of these days i will do some calculations on it to determine its problem.
- i will check your comments about high voltage output connected to low voltage input, the CD4001 is a high voltage part but you are correct that i need to adjust the supply voltage to 12V if the input is 12V as well.
So, still a lot of testing to do and i hope you and others build and test the schematics as well on bread/prototype boards to get the errors out.
Again thank you for your help, together we will make this work the way it was supposed to!!!!
ummmmm..... don't we need 14-35v to run a 12v regulator?
I cant find what we need to run a 10v regulator... ???
but what im thinking is to have a stable 12v out from a 12v regulater... you need at least 14v? right?
that could be the reason for the 10v regulator?
also something i wanted to point out that i think we need to add is the "voltage amplitude control"
i will attach the diagram.
this would be needed to control the output of the cell... see the 2N3055 in the voltage amplitude control circuit is the one mounted on the VIC coil set card yes???
and on that 220 resister just leave it as external connection so we can play with it?
thoughts ? good work sharky and Dan!
PS, after you make those changes could you post the newest working folder of the VIC card. ?