Re: Motorcycle flasher problem.


Well I changed the zener to a 3.3 zener. The slight differnece now is
that the light now is on. Still no flash.

I tried to concentrate on the base to raise it up. But cant seem to do
it.
First out of frustration I tried to swap the 220k for a 10k. No real
change.

Then I tried to "divide" the current as you suggested. But still no
luck. I didnt have a 1.5k but I did have a 1.2k Resister. So used it
instead. No Luck.

I tried replacing the two 3.3 Zeners with two 4v Zeners Still no luck.

I have now tried to Remove Emitter and test the voltages as suggested
in previous post. I do not now get the >12 volts I had in past I only
get .86 at base. Its like the lower 3.3 zener has reduced this
voltage. Please see the schematic below. It has new tested voltages
with the 3.3 Zener. This schematic is with the EMITTER DISCONNECTED.




+o----------------------,
| + |
(2.9) | |
.------------.-|<-.----o--------------o------------------. |
Lamp
| 1N4148 | | | .-.
| . - . | | Mosfet | ( X )
| .------. | | IRFZ34 | '-'
o | T R | | | 60v 30A | |
| |2n3906| o | 0.050 Ohm | |
|(2.93v) '------' | | | |
.-. | | | .-. | Front | |
| | 100k | | | | | 220k | .--o---. | |
| | E B C | | | | | | |
'-' '-' | | | | |
|(1.97v) | | '------' | |
o-----. o | | | | | |
| | TR 2N3906 | | | | | | |
| | | | | | | |
| [Emitter Removed] | | G D S |
'--.
| | E | | |
|
| (Q1)>| (.86v) | (Q2) |(2.93 v) |3.3
|
| |-----B--------o o---o |
1N4728|
| + /| | Mosfet | | |Zener
|
--- | C | VF5408 | D | |
|
--- |(1.97v) | ||-+ - /--/
|
10uf |(0v) | 10k (1.79v)| G||<- ^ ^
|
/16v | '----|___|-------|----o------||-+ | |0v
|
Elec | | | | | |
|
trol | | .-. o---o |
|
ytic | 3.3Vz | | |100k | S |
|
| 1N4728 /--/ | | | |
o--'
| Zener ^ '-' |(0v) | +
| |(0v)|(0v) | |
o----------------------o----o---------o------------------'
| - -
'------------------------o




Then I tried to remove the Mosfet from the equation completely. See
the Schematic below. It has no mosfet and the EMITTER DISCONNECTED and
the COLLECTOR DISCONNECTED. So the only thing actually connect to the
Transistor is the base. See the voltages.



+o-------,
| + o
Diode1N4148 (2.93) | | /
.------------.-|<-.----o--------o---. |Lamp
| Anode | | .-. /
| . - . | | ( X )- ---
| .------. | | '-' \
o | T R | | | | \
| |2n3906| o | o
|(2.72v) '------' | | |
.-. | | | .-. | |
| | 100k | | | | | 220k | |
| | E B C | | | |
'-' '-' | |
|(2.69v) | | |
o-----. o | |
| | TR 2N3906 | | |
| | | |
| [Emitter Removed] | | '--.
| | E |(.86) | |
| (Q1)>| (.86v) | |3.3 |
| |-----B--------o |1N4728|
| + /| | |Zener |
--- | C | | |
--- | | /--/ |
10uf |(0v) | 10k | Collector ^ |
/16v | '----|___|-------|----Removed |0v |
Elec | | (open) | |
trol | | | |
ytic | 3.3Vz | | |
| 1N4728 /--/ | o--'
| Zener ^ | +
| |(0v |
o----------------------o----o---o---'
Anode | - -
'---------o


Perhaps makeing the circuit simpler (initially) can diagnose the
problem.
I wonder if the light has some effect or as you mentioned the power
supply.

If I put a cap across the + and - where it comes out of the adapter.
Should I use an electroliytic cap. and do I put + on + and - on -.

Regards

And Happy New year.
I suppose you could say this darn thing is spanned the years.

.

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