Getting a JVC CD receiver to work

[Perry Babin]

You're not getting any acc voltage to the regulator. What's the voltage on each side of R902?

Place the black meter probe on chassis ground. Place the red meter probe on the point where you need to measure the voltage.

 

[DeadSpeaker]

0.05

 

[Perry Babin]

Is that on both sides?

 

[DeadSpeaker]

that's only on the side marked by the + on the board. It jumps as high as .11

 

[Perry Babin]

A resistor shouldn't have a + symbol. Are you sure you've found R902?

 

[DeadSpeaker]

No i'm not sure. Is it on the reverse side?

 

[Perry Babin]

What's the DC voltage on the other side of R901?

 

[DeadSpeaker]

Yeah I was looking at the wrong thing. It is 0.03 where R901 and R902 meet. It is 0.11 on the other side of R902.

 

[Perry Babin]

What's the DC voltage on the other side of R901?

 

[DeadSpeaker]

Sorry I'm getting so confused. I meant to say between R903 and R902 is the last post. The side of R901 that I had not measured yet is about 0.11. I have the J3 version, and on that schematic, it shows that it should be connected to the acc wire. I measure almost 12 volts at the ACC pin on the board. The two points are not directly connected as the schematic shows.

EDIT: It seems to me that the ACC pin is connected to the start of a trace, R901 is connected to the end of this trace electrically. The problem is, the start and end of the trace are not connected electrically.

 

[Perry Babin]

You need to find the break between the ACC pin on the board and R901. Measure the voltage every 1/4" or so on the trace (which may go from one side of the board to the other) until you find the break.

 

[DeadSpeaker]

The trace is printed, so I can't measure it. You can see it in the service manual on page 64.

 

[Perry Babin]

It's made of copper with a thin protective coating. Scrape the coating to get to the copper.

 

[DeadSpeaker]

Ok it's not the trace itself, but the little hole that is suppose to connect the traces on both sides is at fault. How would one repair this?

 

[Perry Babin]

Scrape the solder mask from the traces on each side of the board, run a wire strand through the hole and solder it to each side of the board where the solder mask has been removed.

 

[DeadSpeaker]

The hole is too small or might even be blocked. Luckily I have very very small wire sized drill bits. As it is 1:30 at night where I am, I'll do this part tomorrow morning. Thank you for your help. I'll be sure to let you know how it turns out.

 

[DeadSpeaker]

Well it works now! Thanks for your help.