SG8 Pot location

[claudio]

If you hook the right pot up like that, it will operate backward from the other pot

I'm sorry I don't get it, how should the pots be connected ?
Please use the yellow letters/numbers

[RS_]

hook up the C and D connections to the 4 and 5 pins, so that the 2 pots operate the same way. turn clock wise for full resistance and counter clock wise for 0 resistance........

or you can do the reverse of that, and hook A & B to pins 2-3 and C&D on pins 5-6 so it operates in reverse

The way you show it now, they will operate reverse of each other.... usually not a good thing....Confusing.....

[claudio]

hook up the C and D connections to the 4 and 5 pins, so that the 2 pots operate the same way. turn clock wise for full resistance and counter clock wise for 0 resistance........

or you can do the reverse of that, and hook A & B to pins 2-3 and C&D on pins 5-6 so it operates in reverse

The way you show it now, they will operate reverse of each other.... usually not a good thing....Confusing.....

OK thx,
should I get 1/4 W resistors (all of them) or is it ok with 1/2W or 1W ?
added copper on pads 5 and 6... too much ?
anything else to improve ?
here the definitive PCB(?)

almost done right ?

PCB_PCB4Mofinv5_20180521143700.pdf

[claudio]

Looking nice.
A couple minor issues, label all components on the PCB whenever space allows such as C-1, C-2, C-3 and R-1, etc. This will make it easier when referring to the various components. There is a large black space in the center of the 15,000 UF caps. May as well extend the inner runs to fill in this area since it's "free" copper and reduces the load for the etching acid and, of course, improves the current carrying capacity.

Richard Gieser

Thanks Richard,

Richard, RS_ , should I use 1/4W resistors or 1/2W - 1W work anyway ?
I think I will send the PCB to production, it's not so expensive and conductivity is much much better...

updated PCB (for some reason doesn't print labeled components...)

PCB_PCB4Mofinv5_20180521220117.pdf

[RS_]

I would use all 1/4W resistors for around the 555, and 1/2W for the gate resistors.
Chose a bigger component size for the 555 Cap..
Make ALL Pads and Holes bigger...!!! I can not stress this enough...!!!
Make the traces to the 7812 fatter.
Make the trace from the tip41 to the gate resistors fatter.
You can make all the other traces a little more fat to match the new big pad sizes. (Making it Robust, Easy to work on)
make sure that the 4 15000uf component Pad spacing fits the Caps you are going to use....
(they look to close together to me)

Now just being nit pickie, I would add a little to the ends of the fat traces by the 1st mosfet so that the connections are at 90deg to the fat traces. Make the fat trace in front of the 4th mosfet so that that short trace on the Source is short. Make a 90deg connection to the to the cap trace on the 1/3 screw post. Move the 4 screw post down closer to the PCB hole so it's fat trace is straight and short

Will this be silk screened...? If not, I add all the Part number/values to the copper bottom. May have to spread things out just a bit for this to work...
Add all other info to the bottom copper in the empty space in the upper left.
Remember that for this to work, you have to add the text in reverse, so that it will read correctly when looking at the bottom of the PCB....

Looking good other wise..

[RS_]

Richard,

This circuit is not going to run very fast, anywhere from 1 a sec, 2-5 times a sec, depending on the Size of Energizer Filling it and the size of the battery's it is charging......... So skin effect is not a issue. HIGH AMPERAGE is....... FAT, Fatter Traces is always better as you have indicated......

[RS_]

claudio,

I noticed that there are no resistor values on the Sch, so on the actual part values you show on the silk screen, where did they come from.....? 1 meg pots may not give you enough resolution to tune it good..... You can add a resistor in series with the pots, so a 10K pot will tune it in easier. bread board it first....

I suggest looking that version of 555 Circuit up, and then changing the values on your silk screen to match...
The gate resistors need looking at too... 1K for both is not correct..... Needs something like a 220ohm as the resistor from the Tip41, and a 10K pull down resistor.

[Faraday88]

True, I don't see a frequency per se, but I do believe there are spikes with fast rise times. Rise times, as I understand it, are to be as fast as possible. And fast rise/fall times are the same as high frequency as far as inductance, capacitance and skin effect goes so the high frequency rules apply even if we have one high frequency pulse (such as one microsecond) every ten minutes.
Correct me if I am in error but I believe that's how this circuit works.

Hi Richard,
Yes, you are right! its called 'Burst frequency' and it is same as what you rightly described it!! and they are accompanied by Skin effect and Proximity effect..where the track Inducatnce and inter track Capacitances all come into play. as far as the dissipation is concerned, I2R still applies since its the Eddy current the amounts for the power loss and the average time of these 'Burst Frequency'if be considered.
Best Regards,
Faraday88.

[claudio]

claudio,

I noticed that there are no resistor values on the Sch, so on the actual part values you show on the silk screen, where did they come from.....? 1 meg pots may not give you enough resolution to tune it good..... You can add a resistor in series with the pots, so a 10K pot will tune it in easier. bread board it first....

I suggest looking that version of 555 Circuit up, and then changing the values on your silk screen to match...
The gate resistors need looking at too... 1K for both is not correct..... Needs something like a 47ohm as the resistor from the Tip41, and a 10K pull down resistor.

This comes directly from the JB Intermediate Book (pages 46-48) "Discharge circuit", JB and Mr. Lindemann keep reminding to stick on what JB is suggesting for this to work, for the resistors the book is saying "form 2k to 10k" or "anything between" and so on
of course I will bread board it first
will update PCB later on..
please suggest values for the components, now components are labeled..
regards



more copper...
PCB_PCB4Mofinv5etching_20180522110243.pdf

[claudio]

Looking better all the time, Claudio.
The black space above R3 and R5 could be filled in with blue and also the area between C3 and C4 which would give a large blue area near the middle of the CB and improve conductivity. There's more room above Terminal 2 to widen the run to C4. There's room to the left and also above Terminal 1/3 to add more blue. All this copper has already been paid for. No sense to etch it away if it will improve conductivity. The spacing under C1, C2, C3 and C4 between the plus and minus runs looks good.

done

PCB_PCB4Mofinv5etching_20180522120235.pdf

[RS_]

I do not have the intermediate handbook... As i built most of the stuff in it, way before it was written.....

so it includes a bill of materials for all the part values...?

I looked at my Pulser Sch's and have 220 ohms on the Gates and a 10K pull down resistor.....


forgot that the rise time part of a real fast sharp signal, acts like the skin effect in high Freq circuits....... This is also a good reason to have short fat traces, so that the inductance is as low as possable....

[RS_]

2 other PPL helped me write the very first Bedini SG/SSG Build and Charging guide. I Kept it updated with the things I was learning until 2012.... now the SG Handbooks are Bedini / PL approved Guides.....

[claudio]

I do not have the intermediate handbook... As i built most of the stuff in it, way before it was written.....

so it includes a bill of materials for all the part values...?

I looked at my Pulser Sch's and have 220 ohms on the Gates and a 10K pull down resistor.....


forgot that the rise time part of a real fast sharp signal, acts like the skin effect in high Freq circuits....... This is also a good reason to have short fat traces, so that the inductance is as low as possable....

page 46-48 shows the discharge circuit parts and specs very precisely, my PCB is based on that...

PCB ready for etching...
PCB_PCBetching_20180524222147.pdf

[RS_]

Looking good,
I would still make the 100uf cap a bigger size component pad spacing and, change the other small cap to match......
make the holes on the all the resistors, pot's, small transistors, and small caps a little bigger, and i think you will be ready to have boards made......

[RS_]

one other thing i would do, is add a LED and resistor to the output of the 555, so you can see how fast it is dumping the caps