8 Transistor SG Kit Not Starting

[rsargent52]

I finally finished building my 8 transistor SG kit and am having some troubles getting it to run. Wanted to see if anybody had any ideas on what I might have wrong. Here are some of the specs:
Both batteries are new lead-acid 8ah motorcycle batteries. The Primary battery is charged to 13.4v and the Charging battery is charged to 11.4v.
There are 19 magnets connected to the outer rim of an aluminum bike wheel that is about 23" diameter.
The gap between magnets and the coil is about 1/4".
I am also using the 12ohm 10W resistor on the trigger coil. (Currently I just have 1 Power Coil and the Trigger Coil connected) - set up to run in Attraction Mode.
I think I followed the instructions and what has been posted here, but may have missed something.
Going to try to attach a pic and a wiring diagram to show better what I put together. I did not get into the wiring of the SG board as it is the one I purchased.

Thanks for any help!
Randy -

[Branch Gordon]

It looks like your coil is upside down. The side with the rods sticking out should be down, away from the magnets. I would recommend larger batteries too...at least 14AH.

Is your frame also aluminum?

I finally finished building my 8 transistor SG kit and am having some troubles getting it to run. Wanted to see if anybody had any ideas on what I might have wrong. Here are some of the specs:
Both batteries are new lead-acid 8ah motorcycle batteries. The Primary battery is charged to 13.4v and the Charging battery is charged to 11.4v.
There are 19 magnets connected to the outer rim of an aluminum bike wheel that is about 23" diameter.
The gap between magnets and the coil is about 1/4".
I am also using the 12ohm 10W resistor on the trigger coil. (Currently I just have 1 Power Coil and the Trigger Coil connected) - set up to run in Attraction Mode.
I think I followed the instructions and what has been posted here, but may have missed something.
Going to try to attach a pic and a wiring diagram to show better what I put together. I did not get into the wiring of the SG board as it is the one I purchased.

Thanks for any help!
Randy -

[Tom C]

randy,

I am not sure what you mean by coil top and bottom. I prefer coil start which is the wires coming off the inside of the coil, and coil end, which is coming off of the last wrap aroung the coil. the trigger wire coming off the coil start goes to primary negative and the trigger wire coming from the coil end goes to the 12 ohm resister. cannot tell if that is the way you have it. also you want the coil top to be flush with the core ( the extra should be hanging out the bottom of the coil)

This is a gen 1 prototype board so it does not have the binding post for the 12 ohm like yours does, but it is the same otherwise. the coil start is also the bottom of the coil when mounted next to the wheel.



Tom C

[rsargent52]

Thanks - looks like my wiring is right. The coil from the kit was labeled "Top" and that is facing up. Looks like my wiring is ok. So I will push my core down so it is even on top - that makes sense. Sounds like it is ok if it is hanging out the bottom, so I don't have to cut the rods.
My frame is steel, but it is isolated from the coil and electronics with wood. The magnets are isolated with the aluminum rim. I did notice the spokes are steel and do conduct through to the steel frame, is that ok? The magnets are spaced above where the spokes connect to the rim by about 1/8".
I will give it another whirl!

[Tom C]

yes there is a coil bottom and top and also a wiring start and end. the nature of an electromagnet..... I would encourage you to get rid of the steel complety. you get eddy currents that will diminish performance. please post a close up photo of the circuit board completely hooked up.....

did you remove the enamel from the ends of the coil wires?

Tom C

[rsargent52]

Have to work on this between a busy work schedule. I fixed the coil issue and still no go. LED does not light up. I am still working with just one power coil - wasn't sure if you meant to connect all the coils. Held off on that as the instructions I received suggested getting it to work on just one coil first.
I will work on getting rid of the steel supports, but they are pretty isolated by wood. Closest distance from the coil to a steel upright is just over 7" and about 8" between circuit board and closest upright. I would hope that that would not totally prevent operation. I will look at a wood and aluminum replacement though.
As requested, I am attaching a few close up pics showing wiring connected. Everything seems to be wired correctly. I did take the enamel off the coil wires. I have run continuity checks to insure I am using the correct wires and have good connections.

Are there any measurements I can try taking at selected points to find if the issue is a transistor, resistor, or another component?
Thanks

[Tom C]

I would assume you metered out the one wire to make sure its the same at both ends...... I would go ahead and hook all the strands per the sg instructions. and give it a whirl.

Tom C

[ErikN]

Are there any measurements I can try taking at selected points to find if the issue is a transistor, resistor, or another component?

[ATTACH=CONFIG]2978[/ATTACH]

Hello rsargent52,

Here are a couple things to try:
1) disconnect the batteries (primary first, then charge) and measure continuity between the trigger pads on the board (Primary - & both sides of R17). I've occasionally had the enamel prevent contact on the terminals even if it's been mostly scraped off. (If it's open circuit, recrimp, solder redo the screw terminals until you have low ohm measurement, then move to step 2)
2) using a multimeter or oscilloscope, measure the voltage between the primary negative terminal (on the board) and the base of the transistor you have connected. (If you measure continuity between these points, it should measure about 470ohms higher than before). Now spin the wheel as fast as you can and note the voltage on the meter. This voltage needs to be +.7V or greater to fire the transistors. If this checks out move to step 3.
3) Connect ALL the power windings to the primary + (currently you only have 1 connected). Leave the single wire connected at the other end of the coil. Reconnect the batteries (charge battery first, then primary). Spin the wheel and see if it starts running, or if you can hear the coil firing. If it fires then different power windings were being used). If it fires but doesn't spin, you could have too much friction (either mechanical or magnetic) in your SG (Have you done a freespin test?), if you connect the remaining wires to the transistor bases and try running it again.

To test the free spin time, remove the coil and spin the wheel as hard as you can and time it until it comes to a complete stop. This should be a minimum of 7-8 minutes, but ideally over 20. In your setup, I suspect the perforated angle will negatively impact your free spin time. This won't prevent the machine from running and charging batteries, but it will reduce the overall efficiency of the system, so you may want to replace the angle with wood at some point. If you do, please redo the free spin time and let us know what you get. This will help other see the impact small changes have on the SG.

Hope that helps!
Erik

[ErikN]

I would assume you metered out the one wire to make sure its the same at both ends...... I would go ahead and hook all the strands per the sg instructions. and give it a whirl.

Tom C

rsargeant52,

Tom's method will save time over my suggestions.

Erik

[Yaro1776]

Similar Issues

Randy,

I have a backup board (identical to your 8 trans) that I tried this morning and it will not light up the neon with only one coil wire connected. So I then connected two opposing coil wires and spun the wheel - I could hear it working (slight rumble), but could not get the neons to light up. I then progressed to four opposing coil wires. Definitely could hear the circuit rumble this time and when the +charge cable was removed from the charge battery the four neons lit up. Same for three coil wires.

Note that I had similar frustrations on my initial start up due to my obvious inexperience - turned out that the termination on the trigger wire was not good enough and that I did not spin the wheel fast enough...

Hope this helps you,
Yaro

Thanks Erik for the transistor firing info..

[rsargent52]

Thanks guys, for all the support! So I have stepped through all of the recommendations. I set it up with all 8 coil strands active. First, here are readings I have taken:

Voltage Readings - Mulitmeter reading with + conductor on battery and - conductor on board screws
Primary Battery = 13.1v Seconday Battery = 12.5v

Board Location Battery Terminal Voltage
Start Power Primary + 0
Start Power Primary - 13.1
Start Power Secondary + 12.6
Start Power Secondary - 12.6
Charge + Primary + 12.5
Charge + Primary - 25.2
Charge + Secondary + 25.2
Charge + Secondary - 12.6
Primary - Primary + 13.3
Primary - Primary - 0
Primary - Secondary + 25.2
Primary - Secondary - 13.1
Trigger Primary + 13.1
Trigger Primary - 0
Trigger Secondary + 25.2
Trigger Secondary - 13.1

Here is Continuity Testing with Batteries Disconnected
Point 1 Point 2 Reading
Trigger Primary - 3.1
Trigger after Resistor Primary - 15.2
Trigger Feed to Primary - 3.1
All Start Power Poles Feed to Primary + 1.6
All Start Power Poles Feed to Seconday - 1.6
Center Pole Transistor Feed to Primary + 1.6

Here are notes on testing all the points suggested:

When I take the system apart to replace metal with wood, I will do a free spin test of the wheel without the coil and see how it does. This is a pretty good bicycle rim though, and it does spin fairly freely right now. The only resistance I am noticing is the magnets passing the rod.

Started with a gap between magnets and rod of about ¾”. Then moved it in to a ¼” gap. When at a close gap when a magnet is close to the rod it pulls in to align. If the magnet is off set from the rod more than 1”, it does not pull in.

With secondary battery connected, then when I connect the primary if a magnet is directly over the coil a noticeable vibration and clicking that you can hear once. But no LEDs lit up. This happens when I have 4 or more leads connected with it getting stronger as I add more leads.
I left the secondary battery disconnected, and connected the Primary Positive, then touched the lead to the Primary Negative and the LEDs all lit up and turned off.

As suggested, checked voltage at transistor. Outer pins show now voltage. Center pin reads 13.1v – when I spin the wheel it will have drops down to 12.91v when wheel is spinning fastest, then as the wheel slows down voltage goes back up. Based on comments, it sounds like the voltage is going the wrong direction (what could cause that?). Outer pins of transistors do not show any readings but mv when stationary or when wheel is spinning.

With the primary battery disconnected, I accidently reversed the connections on the charge battery and the LEDs lit up. This was just touching the pole rapidly then jumping off. Re-tested readings and nothing seems to have been hurt. If something looks incorrect please feel free to slam me!

Below is a pic with everything connected. Thanks again - I am determined to make this puppy fly!

[rsargent52]

Here it is with all connections:

[Tom C]

Randy,

any chance you could get it in focus, its hard to see what's is where.

Tom C

[rsargent52]

My camera broke so I only have my phone to take pics with and for some reason it is having trouble focusing.
Here are some more shots from a couple angles and focal points - hopefully it shows better.
Maybe the issue is my metal frame - I will try to get time to swap it out tomorrow.

[Yaro1776]

Randy,

To my beginner's eye your connections all look right as shown in the pics - the experts can verify your wiring. But, the last pic of the coil to magnet interface shows that the coil face is not centered parallel to the magnet face (may be the camera angle). If your wheel mount base is level as it sits, the center of the wheel axle should be directly above the center of the coil rods. The last pic suggests that the coil be moved to the right about an inch or so for the magnets to be parallel to the face of of the coil and rods as they rotate by. This may help...

By the way the gap dimensions in your post came through as gibberish, this may be a fault/quirk in the forum software.

You are nearly there,
Yaro