C114 is in parallel with C118
C118 and C157 both measure 10.57nf
The voltage across C118 was 0 volts when I measured it .
I noticed it blew the positive regulator again
C118 and C157 both measure 10.57nf
The voltage across C118 was 0 volts when I measured it .
I noticed it blew the positive regulator again
I don't understand how the FET could have blown with it clamped and the current limiting of the lamp.
I will rebuild the circuit again replacing the fet the cap and check the other components and insert the bulb back in circuit and post my results
.026 volts .
That’s with black probe on ground terminal .
Where do I place the black probe ? Not sure what you mean
That’s with black probe on ground terminal .
Where do I place the black probe ? Not sure what you mean
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Black probe on ground terminal and red probe on source leg Orhwr terminal or bulb I get 83.9 volts
Ok the cap was shorted C118 .
Once I replaced the cap it blew the new cap and the regulator Instantly .
I removed the cap and the regulator .
Where do I go from here
Once I replaced the cap it blew the new cap and the regulator Instantly .
I removed the cap and the regulator .
Where do I go from here
Do you have something like a 40w?
Is the diode across the capacitor in the circuit?
Are you using exact replacement parts?
Is the diode across the capacitor in the circuit?
Are you using exact replacement parts?
I can get a 40 watt bulb .
The diode is in circuit across the cap it tests fine .
I’m using IRF540 for the regulator that I got from
Mouser .
The 2N5401 (2L ) is the same as the original .
The MMBTA42 (1D) i replaced with mouser parts but they say K3M on the transistor .
The cap was replaced with original value .
And the .1uf caps were replaced with a .1uf 100volt smd cap same as the original
The diode is in circuit across the cap it tests fine .
I’m using IRF540 for the regulator that I got from
Mouser .
The 2N5401 (2L ) is the same as the original .
The MMBTA42 (1D) i replaced with mouser parts but they say K3M on the transistor .
The cap was replaced with original value .
And the .1uf caps were replaced with a .1uf 100volt smd cap same as the original
The diode should be something like an 18v Zener. Is it?
If it's parallel with the capacitor, I don't understand what's killing the capacitor.
Is the bulb a standard incandescent bulb (not CFL or LED)?
If it's parallel with the capacitor, I don't understand what's killing the capacitor.
Is the bulb a standard incandescent bulb (not CFL or LED)?
The diode is a 1N4001 .
I’m using an incandescent light bulb (Older style for houses ) so it’s not a led or a newer type bulb .
I’m using an incandescent light bulb (Older style for houses ) so it’s not a led or a newer type bulb .