Ok, So I did this write up a couple of weeks ago for the Yamaha Enduro Forum. A LOT of the older Yam DT, MX, YZ, AT, CT bikes run AC magneto ignition systems, and I know there's some folks over here that are working on more than just XS's. This will also work for anyone running a Joe Hunt Mag on their XS. If you have ever looked into building your own magneto timing buzz box you know that all the DIY plans are from the 70-80's and are transistor based with the necessary parts no longer being produced. SOOOOO, I worked out a newer version with modern parts that are readily available. The total cost should be around $40 this is compared to a cost of around $70 after shipping for a ready made unit so the savings aren't huge but... You can say you made your own and have $30 to spend on more parts...
Full list of needed components ( this could vary depending on the board configuration you order )
1. Code oscillator board $17
2. 9V battery $3.00
3. 9V battery leads $1.00
4. Test leads (alligator clips and wires) $2-3
5. Speaker 8ohm 5W ish $4.00
6. Enclosure 4X6" $11.00
7. Knob for 1/4' (6mm) potentiometer shaft $1.00
8. 1/4" mono phone plug for test leads ( if 1/4 jack chosen) $3.00
9. SPST toggle switch $2.00
This puts the total around $45 if you have to buy ALL the components. This is a savings of around $30 (more money for motorcycle parts!) if you were to buy a ready made buzz-box on the low end.
I found a modern IC based code oscillator on eBay, these can be ordered in customized configurations from the seller. They will add whatever connection points you would like from the menu and assemble the board for you for around $17 the rest was just leads, a speaker, battery leads, battery, a knob, and an enclosure.
Mine has a 1/4” mono phone Jack for the leads but you can order it with screw terminals if you like, I used a set of battery leads from an old broken timing light and a radio shack 1/4” mono phone plug with screw terminals. The speaker was a 3.5” 8
️ Speaker out of an old CB base station.
I will follow up this weekend with pics of the unit in an enclosure, a video, and wiring diagram.
Full list of needed components ( this could vary depending on the board configuration you order )
1. Code oscillator board $17
2. 9V battery $3.00
3. 9V battery leads $1.00
4. Test leads (alligator clips and wires) $2-3
5. Speaker 8ohm 5W ish $4.00
6. Enclosure 4X6" $11.00
7. Knob for 1/4' (6mm) potentiometer shaft $1.00
8. 1/4" mono phone plug for test leads ( if 1/4 jack chosen) $3.00
9. SPST toggle switch $2.00
This puts the total around $45 if you have to buy ALL the components. This is a savings of around $30 (more money for motorcycle parts!) if you were to buy a ready made buzz-box on the low end.
I found a modern IC based code oscillator on eBay, these can be ordered in customized configurations from the seller. They will add whatever connection points you would like from the menu and assemble the board for you for around $17 the rest was just leads, a speaker, battery leads, battery, a knob, and an enclosure.
Mine has a 1/4” mono phone Jack for the leads but you can order it with screw terminals if you like, I used a set of battery leads from an old broken timing light and a radio shack 1/4” mono phone plug with screw terminals. The speaker was a 3.5” 8
️ Speaker out of an old CB base station.I will follow up this weekend with pics of the unit in an enclosure, a video, and wiring diagram.
