Bedini Schoolgirl

[lis_wang]

Hi Aaron!

As far as the coil goes, I followed the directions for winding as you set forth above. When I energize it with the (+) coming off the top lead and (-) off the bottom, it's a north pole with quite a bit of kick (I tested both the #24 portion and the #26 portion, and both are quite powerful as electromagnets ). I verified north on my magnets by hanging one on a piece of thread and seeing which side faced north, and labeled the side facing that way as "north". I then checked all the rest of my magnets by checking for repulsion with the known north face and labeled all the repulsed sides "north" as well. The core is made up of 2 1/2 inch nails epoxied together with the heads cut off, cut to length, and the points sanded down.

The components are the stock ones suggested by the schematic: A 2N3055 transistor, a 1N914 diode, and a 10 ohm, 1/2 watt resistor (too much wattage? seems unlikely to me). I'm using a battery consisting of 1.5V AA cells--one at 6V/2.3A, and another at 12V/8A. There isn't any deviation from what's suggested up above other than the lack of turns on my coil. Also, it doesn't induce enough current even if I give the rotor a good spin. Pictures follow. In the closeup of the circuit, the clips are not shorting out with the collector. I decided to go with clips after losing the second transistor and thinking that my diode had blown. This way, I can test components without having to solder/desolder anything.

Also, I connect (+) from my battery to the red lead coming from the top of the coil, and connect the (-) to the emitter (the clip on the bottom right of the circuit closeup). The second transistor blew when I gave the rotor a good spin and it acted as if it were magnetically braking the rotor--the coil and transistor heated up quite a bit on that run. I have since verified and reverified that the coil is hooked up correctly to the battery and that the coil produces a north magnetic field out the top that repulses each and every magnet on the rotor. The only thing that looks different in my setup is the number of turns on my coil, but there could be something else that I've overlooked.

Hi, Shamus

Are you using two CDs to be a roller?

[lis_wang]

Bedini School Girl Science Fair Motor discussion. This isn't for the versions that charge batteries. This is really for beginners who just want to learn more about the very simple roller skate version.

Get a copy of the only Authorized Bedini SG Handbook - Bedini SSG

Dear Aaron

Can I use Ceramic (Strontium Ferrite) magnet, grade Y30BH? I cannot find grade 8 ceramic magnet locally. What is the size of magnet?

Thanks for your help

[Aaron]

Bedini SG

Lis, here is the old video:
https://www.youtube.com/watch?v=zNeDySD81bM

[lis_wang]

Lis, here is the old video:
https://www.youtube.com/watch?v=zNeDySD81bM

Dear Aaron

Thanks for your reply.

I have another question in my mind. Besides the output of SG can charge battery, can it be used for lighting up a normal fluorescent lamp, for example 12W energy saving light bulb? If can, I think SG is more meaningful.

[lis_wang]

Lis, here is the old video:
https://www.youtube.com/watch?v=zNeDySD81bM

From your video, the coil spool does not looks like to be 1" in OD and 1.5" in length. What is the actual size of your spool?

Thanks

[Aaron]

Bedini SG

Lis,

That is put up now so I can't measure it but it is built according to the specs in the old Bedini notes from 10 years ago.

Get this book: Bedini SG

That will answer almost every question you have about getting started.

[lis_wang]

Lis,

That is put up now so I can't measure it but it is built according to the specs in the old Bedini notes from 10 years ago.

Get this book: Bedini SG

That will answer almost every question you have about getting started.

I bought the book. And I checked the size of spool is: 3.25” in high, 3.5” in diameter with central cylinder 0.75 in diameter. It is very much different

[Aaron]

coil size

I bought the book. And I checked the size of spool is: 3.25” in high, 3.5” in diameter with central cylinder 0.75 in diameter. It is very much different

Ok, you're talking about the big spools. That is on the bicycle wheel SG/SSG.

Mine is like in the diagram with the roller skate wheel - that is in the book - in that particular video that is.

[lis_wang]

Ok, you're talking about the big spools. That is on the bicycle wheel SG/SSG.

Mine is like in the diagram with the roller skate wheel - that is in the book - in that particular video that is.

Will it be a problem if I used the big spools?

[Aaron]

spool size

Lis,

You an use a big spool and wind less wire on it. It will just be cumbersome but will not effect the running of the machine (if you're planning on a small roller skate wheel build). However, if you're not going to put on many turns and use smaller wire, I'd use a spool that is at least shorter so you get a more condensed magnetic field at the top.

[lis_wang]

Lis,

You an use a big spool and wind less wire on it. It will just be cumbersome but will not effect the running of the machine (if you're planning on a small roller skate wheel build). However, if you're not going to put on many turns and use smaller wire, I'd use a spool that is at least shorter so you get a more condensed magnetic field at the top.

Hi, Aaron

Thanks for your help. I already ordered a coild spool on line last night and I will try when it arrives.

[Aaron]

Bedini SSG

Ok, hope it works out for you!

Most of the SG/SSG support is here:
Bedini SG - Official Monopole Forum

[lis_wang]

Discharge the battery

There is an official Bedini SG manual finally available: Bedini SSG

You'll probably get it working on the first try.

Use a 10ohm resistor to start with, easier to get it running on that. Not as efficient, but just get it to work.

1 X 10ohm resistor
1 X 1N914 diode
1 X MPS8099 transistor or RCA3055 or 2N3055 either of those will work fine

Get enough wire of #23 and #26 or closest you can find for those. Enamel coated magnet wire..enough to wind about 600 turns on the coil to the dimensions in those schematics. Make sure to wind it so that when you put + top the top of the coil and - at the bottom that the magnetic field on the coil is NORTH at the TOP. Wind both of those wires together at the SAME time around the spool.

The core for the coil can be a soild piece of iron or use a bunch of smaller pieces of welding rod cut to lenght and bundled together.

The transistor has a collector, emitter and base. The collector is the input, the emitter it the output. With these NPN transistors, there is no connection through the transistor from collector to emitter. The faucet is shut off basically. To make the connection, it requires a bit of current at the base...that is what the trigger wire is for. That turns it on and when the power is no longer at the base, the transistor shuts off. It is just an off and on switch triggered by the base.

When you buy the transistor, the package will give you a diagram or you can find it online which lead is what. BCE are the 3 you need to know. Just connect the coil wires, diode and resistor to each other like in the diagrams John drew.

The resistor doesn't matter which way you put it. The diode, the little black stripe needs to be towards the base of the transistor.

Make sure the wheel spins really, really easily. One little spin and it just keeps going. You can make it like mine where the wheel spins around the shaft or you can make it fixed to the shaft so the shaft spins in some bearings in the frame uprights.

You can use regular ceramic magnets on the rotor. Just make sure North is facing out on all 4 magnets so that south are all facing towards the axle.

The little black sealed gel cell batts are good ones to play with for starters. Use 12 volt ones.

When it is all hooked up, you give a slight little spin on the wheel and it will just start speeding up as fast as it can go.

When you get it running with these parts (use the 10ohm resistor), then you can switch out the resistor to something like a 680ohm to see if it will run on that. You basically want as much resistance as possible while still letting enough get through to trigger the transistor. That is the idea anyway.

There are a LOT of people around the world who have build these Bedini machines so you won't have a problem getting people to help you out.

If I just connect the primary battery without charging battery, can the circuit used to discharge battery? Thanks

[Sawt2]

If I just connect the primary battery without charging battery, can the circuit used to discharge battery? Thanks

If you attach the primary without a charge battery connected (on a SG circuit)
What you will do is burn out your transistor

[Aaron]

without charging battery

If you attach the primary without a charge battery connected (on a SG circuit)
What you will do is burn out your transistor

That's true - but if the coil is tiny like the little roller skate wheel version, it should be ok. I have transistors 2N3055 - that lasted years without using a charging battery on the circuit.

But if we're in the bigger coils, yes, good rule to always use a charging battery.