Forgot. The bulb is not completely bright as before. Maybe 50-60 %.

 

0V on all collectors is a good sign.
Emitter voltages appear to be rather low. I suspect that there is still a short somewhere.

This is where a thermal imaging camera would come in handy to find the hot spot.
I am going to guess that there must be at least 10W of power being lost somewhere.

 

I am interested in purchasing one if the price is not too much. Any recommendations?

 

Unplug the unit and measure the resistance between BLOW+ and BLOW-.

 

-12.99 meg. ohms.

 

Remeasured and now I get - 2.29 m ohms

 

Q7603 looks something like this:



Apply power and measure the voltage at pins 1, 2, and 3 with respect to GND.
Indicate the pin numbers because EMITTER and COLLECTOR might be swapped.

 

Will do as soon as I can. Got a little emergency with my diabetic son. Will get back to you in a couple of hours.

 

Q7603

Base -4.10 v
Collector 6.41 v
Emitter -4.06 v

 

Is there another board?
Can you post a clear photo of that board?
I am looking for Q7211 and base, collector, emitter voltages with respect to GND.

Again please indicate pin numbers as shown in post #47. It is not certain which is collector and emitter.

 

Q7211

Base -.001 v
Collector 6.06 v
Emitter -0.01 v

 

Ok thanks.
No clue so far.
I think we will have to start removing some connections or jumpers.
We'll continue tomorrow.

 

Ok Thanks.

 

How difficult is it for you to unsolder jumpers on thePCB?

You don't have to unsolder both ends of the jumper.
If you have a solder sucker that will help to clear the solder from the pad and hole. Bend the end of the wire so that it stands upright and easy to extract from the hole.

Let's start by lifting one end of the +B1 and -B1 jumpers coming from the CN7502 connector.
After this is done, apply power and observe the brightness of the bulb.
Measure the +B1 and -B1 voltages coming off of CN7502 connector.

 

I have a solder suckered. I will take a look at what you requested shortly, and will send you the results.

 

B1 + voltage 2.5 v
B1- voltage -2.5v

 

Remeasured: B1+ voltage 4.14
B1- voltage -4.47.
Why did it change?

 

Now B1+ 5.96 v, B1- 4.98

 

We need to go back to the power supply where +B1 and -B1 are generated.


D1201 is the bridge rectifier. Measure between pins 2 and 3 for AC voltage (set your DMM to 600VAC).
You can use J106, pins 1+2 and 6+7.

Measure from pin-1 to GND for DC voltage (set you DMM to 200VDC).
Measure from pin-4 to GND for DC voltage (set you DMM to 200VDC).
J106 pins 4+5 are GND.

 

D1201-Between pin 1 and 2 = 3.4 vac
J106 ground to pin 1= 0.00 vdc
J106 ground to pin 4= 0.00 vdc