7 circuit Bedini SG

[shadow44]

Hi gang! Better late then never! I have a lot of catching up to do. Today I built my first SG. I built it with the help of Johns Book #1. I did it exactly like he said. Cause he says "build it just like this". So I did. or at least as close as I could. I have a close up of the circuit so you can see what I did.

got it all hooked up, and spun the wheel the wrong way. Of course it dident run. then it dawned on me, so I spun it the other way. YeeHaw! she took right off! so to "test" the circuit, I pulled the pos off the charge battery. thats where it went wrong

the 2nd light from the right blinked a couple of times and went out. None of the others came on. I hooked it right back up and it still ran, but slower. so I did a finger temp test on the transistors. 2 on the left were HOT! the others were cold. everything is per spec as far as I can see. So i did some testing, I have no idea how to test BJT's but the values seem consistent except the 2nd one from the left. I put in new diode, no change, new resistor, no change. removed the neon bulb, no change.

eplanation of the picture:
"top of the coil" comes in on the right with the trigger wire coming in through the hole, connected to the resistors. Bottom of the coil connected to the transistors, with the trigger wire coming in thru the hole on the left, connected to the?collector? the pin on the left when upside down
The rest is visible as far as how its assembled.

So what went wrong?

I have got a few days to reflect, as I have to wait on Mouser to ship me new transistors

Any help would be appreciated

pics wont upload. Follow link below.

Also posted here my new SG !! ran then quit.. what did I do wrong?

[BobZilla]

Just a though here after looking at your original pictures,,,

You may be burning up components when you solder them in. Those huge gobs of solder do not cool as quickly as a joint would on a PCP and also being on a metal plate it is going to stay hot.

To improve on it you may consider drilling tiny pilot holes for your components to connect to. Put a tiny bit of solder in the hole then put the component leg on it while it is cool. Take your iron and touch the leg and the drop at the same time and it should slip right in with minimal heating of the component. This will also result in a more balanced circuit because excessive solder can change resistances.

Good luck ---Bob

[Gpilot]

I built a single circuit bu

[brodonh]

Hi Tim C and all,

I want to switch my 16" bike wheel to super pole mags and can you say what is best superpole mag spacing?

Thanks.

bro d

[Tom C]

Hi All,

I been wondering, what are the difference of having one strand coil, and 7 strand coils with one trigger... does the fields in each strand add up? will create a bigger spike? but it will draw more current ?

Thanks.

there is only 1 trigger shared between all the transistor bases. esch strand pulls more current so you get a more powerful charger. more current bigger spike, but it is a non linear exponentisal increase.

Tom C

[TheStone16]

Hi All,

I been wondering, what are the difference of having one strand coil, and 7 strand coils with one trigger... does the fields in each strand add up? will create a bigger spike? but it will draw more current ?

Thanks.

[brodonh]

Hi All,
I've decided to do the same thing that Gpilot is doing. Glad to see him jumping in a getting after it.
I've been upgrading my bike wheel setup to meet the instructions in the intermediate manual.
I have matched trannys and resistors running on an 8 pwr strand coil and also have the cap pulser circuit working and seeing 2.5amp pulses at about once per second.
I'll be rewinding my coil with #20 wire tomorrow and running with 7 pwr strands.

Glad this thread is started so I'll be posting.

Usually when the mag is attracted to the core at turn on, it means that there is a short or a bad transistor.

Tom C is giving a good step by step approach for a relative newbie.

Nice work and the help is here.

bro d

[Gpilot]

coil wires not shorted together internally
bad connections
bad transistors
diodes wrong way
magnets south out not north


take that big circuit off the machine build a single SG circuit like this one. add circuits as it starts running. I see you have insulators on your transistors, good you can leave the coil as is. with all of the components many things could be wrong. if you have the SG book you wil see this coil is in repulsion mode, do not worry about that, run your coil the way you have it one power strand one trigger strand in attraction mode.

[ATTACH=CONFIG]1773[/ATTACH]



Tom C

Can you tell by the picture if my diodes are the right way? The magnets i am pretty sure are N out. When i plugged a battery into the coil alone, it does repel. The transistors I will need to test again, it is possible I burned them up during unsuccessful testing. The connections will be resoldered. I am building a single SG circuit now, and will update this evening on the findings.

[Tom C]

I got the neon to fire when i disconnect the secondary batt. The machine still doesnt function properly, but i cant get it to run on just one transistor. Any tips?

coil wires not shorted together internally
bad connections
bad transistors
diodes wrong way
magnets south out not north


take that big circuit off the machine build a single SG circuit like this one. add circuits as it starts running. I see you have insulators on your transistors, good you can leave the coil as is. with all of the components many things could be wrong. if you have the SG book you wil see this coil is in repulsion mode, do not worry about that, run your coil the way you have it one power strand one trigger strand in attraction mode.





Tom C

[Faraday88]

Hi Pal!,
i see that your Trigger connections have to be reversed.. and you will be on track..! having that done most of the transient (Radiant Spike!) protection look very much in place.. neat and effortful work ..!
Rgds,
Faraday88.

[Gpilot]

desolder the base resistors which is the trigger that will turn off the transistors you are not using, leave one connected. then take the wire bundle from the coil and split it out so you can add one wire at a time to the circuit, remove the wires going to the transistors so you have only one power winding connected at a time. use your meter to make sure the power winding connected is the same at both ends.

Tom C

I got the neon to fire when i disconnect the secondary batt. The machine still doesnt function properly, but i cant get it to run on just one transistor. Any tips?

[Tom C]

Do i just need to desolder 6 of the 7 power wires from their transistors and test again? I have a pretty good multimeter i can use to test my transistors, provided that i dont need to remove them from the circuit.

desolder the base resistors which is the trigger that will turn off the transistors you are not using, leave one connected. then take the wire bundle from the coil and split it out so you can add one wire at a time to the circuit, remove the wires going to the transistors so you have only one power winding connected at a time. use your meter to make sure the power winding connected is the same at both ends.

Tom C

[Gpilot]

Yes one at a time seems like what did then I went to two channels but if your input has 5 amps flowing into to it on the ammeter something is shorted or when you hooked it up in reverse maybe the channels went out the window. Do you have anyway of testing your Trannies?

Mike PS I know this stuff can be a pain for a new born lectronix jockey. LOL

Do i just need to desolder 6 of the 7 power wires from their transistors and test again? I have a pretty good multimeter i can use to test my transistors, provided that i dont need to remove them from the circuit.

[Tom C]

Mike,

I sent you a p.m.

Tom C

[Gpilot]

sounds good buddy, ill do that