Can you show the signal at pin 1?Pin #7 has 1/2 of vcc about 6v
Pin #3 has no voltage at all
Removing 500k resistor will not help.
I also tested with signal generator (50Hz, 50% duty cycle, +/- 10v) nothing happens with that also =(
Can you show the signal at pin 1?Pin #7 has 1/2 of vcc about 6v
Pin #3 has no voltage at all
Removing 500k resistor will not help.
I also tested with signal generator (50Hz, 50% duty cycle, +/- 10v) nothing happens with that also =(
I have tested this circuit on breadboard.Pin #7 has 1/2 of vcc about 6v
Pin #3 has no voltage at all
Removing 500k resistor will not help.
I also tested with signal generator (50Hz, 50% duty cycle, +/- 10v) nothing happens with that also =(
Ok, thanks! I must have fake or defective chips.I have tested this circuit on breadboard.
I used 150k for R1 (no pot)
I swept the input signal from 1hz to 15hz. I tested with both bipolar square and sine wave at 4v pkpk
The Load triggers at 10+0.5 hz (I used an LED for the load)
The wiring shown for the 14pin 2907n in post #18 is correct.
The voltage at pin 3 should rise as the frequency increases. If it is zero and not changing then that is the problem. The voltage at pin #1, the input, must swing both positive and negative for the input comparator to drive the charge pump and make the pin 3 voltage rise.Pin #7 has 1/2 of vcc about 6v
Pin #3 has no voltage at all
Removing 500k resistor will not help.
I also tested with signal generator (50Hz, 50% duty cycle, +/- 10v) nothing happens with that also =(
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