Hifonics XX Chaos

[Perry Babin]

Do you have a large 2 ohm current limiting resistor?

 

[mike49504]

I have a large 1 ohm

If i hook 1 side of the resistor to the positive side of my power supply and the other side to the B+ terminal of the amp.

And the negative of the power supply to the non-bridging speaker terminal

No remote applied

I twist the transformer every which way i cannot see it spark at all .. All lights are off in the room

 

[Perry Babin]

That should be OK.

Connect it in series with the B+ line. Ground the secondary center tap of the transformer. Make NO other connections to the amp. Twist the transformer and look for sparks. Continue doing this until you see the exact point where it's sparking.

insert an insulator between the windings at that point. If it's on one of the terminal windings, Insert a piece of thin cardboard coated with adhesive.

 

[mike49504]

I got this pic from amp guts since im waiting on my new camera to arrive..


I grounded this lead of the transformer and ooked a resistor to the B+ twisted the transformer and cannot get it to spark at all..

The lead has the blue line going to it in the pic

 

[Perry Babin]

The secondary CT is a better point.

Did the current drawn go from 0A to ~12A as you twisted it?

 

[mike49504]

Current draw remains the same as i twist it

 

[Perry Babin]

What is the current draw?

 

[mike49504]

with center tap grounded and B+ hooked up nothing else the current draw is 0

 

[Perry Babin]

Then it appears that the short has been eliminated. You should try to force it to short again so that you can determine the point where it's shorted and insulate it. If you leave it as it is, it's likely to happen again. If it does, it could damage the head unit, the amp or the vehicle (if the shield ground in neither component opens).

Are you sure that the resistor isn't open?

 

[mike49504]

You refering to my current limiter resistor?? Its measures 0.8 ohms

Or which resistor are you refering to?

 

[Perry Babin]

That's the one. Since the current draw never returned, I wanted to confirm that the resistor was OK.

 

[mike49504]

So to check the voltage on the rca's red probe goes on rca shields black goes on ground terminal??

IF so i get -0.13

If i place red probe on B+ and black probe on rca shield i get 13.93 volts

If i put black probe on 2nd center tap and red on rca shield i get:0 volts

 

[mike49504]

Ok now i have to rip this back apart again when i was twisting the transformer to find the short the faces on 2 op-amps blew off..

 

[Perry Babin]

Did you have the RCAs plugged in when you read 0.3 ohms from the B+ terminal to the RCA shields?

 

[mike49504]

No

 

[Perry Babin]

OK. If you ever had the RCAs for your signal source plugged into this amp, check the shields to confirm that they're not open.

Try to find the short again.