How Not to make and Inverter

You can build an inverter with a small 60rpm DC motor. The
motor turns a disk with 4 brushes, 2 on each side of the disk.
The disk is a sandwich of two conductors separated by an
insulator. One of the brushes on each side contacts the
respective conductor, and the other brush contacts an outer
band. Each sector of the band has a resistance. The resistance
is selected so that as the motor spins the disk, the outer brush
on each side contacts the resistive sectors, and it creates a
sinusoid. The signal is then fed into a transformer to create
120VAC. This arrangement runs off of a 12V car battery or a DC
generator.

Disk Sector Resistances

OHMS
one side opposite side
9:00 transition transition
10:00 1M open
11:00 10k open
12:00 0 open
1:00 10k open
2:00 1M open
3:00 transition transition
4:00 open 1M
5:00 open 10k
6:00 open 0
7:00 open 10k
8:00 open 1M

Output voltage is between two conductor brushes.
The first brush goes to 12V through a 100 ohm resistor
The opposite brush goes to ground through a 100 ohm resistor.
The first band brush goes directly to 12V
The opposite band brush goes to ground.

How do you get an appreciable amount of current out of this! ???



--

Jerry G.
======

"Jon G." <jon8338@peoplepc.com> wrote in message
news:422900FE.8020901@peoplepc.com...
You can build an inverter with a small 60rpm DC motor. The
motor turns a disk with 4 brushes, 2 on each side of the disk.
The disk is a sandwich of two conductors separated by an
insulator. One of the brushes on each side contacts the
respective conductor, and the other brush contacts an outer
band. Each sector of the band has a resistance. The resistance
is selected so that as the motor spins the disk, the outer brush
on each side contacts the resistive sectors, and it creates a
sinusoid. The signal is then fed into a transformer to create
120VAC. This arrangement runs off of a 12V car battery or a DC
generator.

Disk Sector Resistances

OHMS
one side opposite side
9:00 transition transition
10:00 1M open
11:00 10k open
12:00 0 open
1:00 10k open
2:00 1M open
3:00 transition transition
4:00 open 1M
5:00 open 10k
6:00 open 0
7:00 open 10k
8:00 open 1M

Output voltage is between two conductor brushes.
The first brush goes to 12V through a 100 ohm resistor
The opposite brush goes to ground through a 100 ohm resistor.
The first band brush goes directly to 12V
The opposite band brush goes to ground.

In article <38un54F5sibl4U1@uni-berlin.de>,
"Jerry G." <jerryg50@hotmail.com> wrote:

How do you get an appreciable amount of current out of this! ???

Also 60 rpm gibes you 1 cy/sec

--

Jerry G.
======

"Jon G." <jon8338@peoplepc.com> wrote in message
news:422900FE.8020901@peoplepc.com...
You can build an inverter with a small 60rpm DC motor. The
motor turns a disk with 4 brushes, 2 on each side of the disk.
The disk is a sandwich of two conductors separated by an
insulator. One of the brushes on each side contacts the
respective conductor, and the other brush contacts an outer
band. Each sector of the band has a resistance. The resistance
is selected so that as the motor spins the disk, the outer brush
on each side contacts the resistive sectors, and it creates a
sinusoid. The signal is then fed into a transformer to create
120VAC. This arrangement runs off of a 12V car battery or a DC
generator.

Disk Sector Resistances

OHMS
one side opposite side
9:00 transition transition
10:00 1M open
11:00 10k open
12:00 0 open
1:00 10k open
2:00 1M open
3:00 transition transition
4:00 open 1M
5:00 open 10k
6:00 open 0
7:00 open 10k
8:00 open 1M

Output voltage is between two conductor brushes.
The first brush goes to 12V through a 100 ohm resistor
The opposite brush goes to ground through a 100 ohm resistor.
The first band brush goes directly to 12V
The opposite band brush goes to ground.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

Nick Hull wrote...

Jerry G. wrote:

How do you get an appreciable amount of current out of this! ???

Also 60 rpm gibes you 1 cy/sec

It's baadd, but not that bad, Jon G likely meant a 6000rpm motor.

"Jon G." <jon8338@peoplepc.com> wrote in message
news:422900FE.8020901@peoplepc.com...
You can build an inverter with a small 60rpm DC motor. The
motor turns a disk with 4 brushes, 2 on each side of the disk.
The disk is a sandwich of two conductors separated by an
insulator. One of the brushes on each side contacts the
respective conductor, and the other brush contacts an outer
band. Each sector of the band has a resistance. The resistance
is selected so that as the motor spins the disk, the outer brush
on each side contacts the resistive sectors, and it creates a
sinusoid. The signal is then fed into a transformer to create
120VAC. This arrangement runs off of a 12V car battery or a DC
generator.

Disk Sector Resistances

OHMS
one side opposite side
9:00 transition transition
10:00 1M open
11:00 10k open
12:00 0 open
1:00 10k open
2:00 1M open
3:00 transition transition
4:00 open 1M
5:00 open 10k
6:00 open 0
7:00 open 10k
8:00 open 1M

Output voltage is between two conductor brushes.
The first brush goes to 12V through a 100 ohm resistor
The opposite brush goes to ground through a 100 ohm resistor.
The first band brush goes directly to 12V
The opposite band brush goes to ground.

--
Thanks,
- Win