Max 100 frequency counter

[kaos513]

Noticed the counter has been worked on,as I seen some new solder under the board, my phone ran out of juice hopefully i will uplaod them tonight thank for everybodys help here i apreciated it alot.

 

[kaos513]

Check and see which regulator you have. I'm willing to bet it is a 7812 or maybe a LM317. Check and see the if DC volts are on the top of the big capacitor and then on the output of the regulators. I don't know what your skill level is so forgive me if you think I am talking down to you.
Look up the various 4000 series chips and check for the voltage on the power input pin and see if it is there.
Also do you have an oscilloscope? The following link is for the main chip inside.
http://pdf1.alldatasheet.com/datasheet-pdf/view/71308/LSI/LS7031.html

I
I have all channel display replacements.

 

[kaos513]

I

I have all channel display replacements.

Also i will try to reflow the board with new solder.

 

[Tallman]

I

I have all channel display replacements.

You might not need those. If the power supply is not working properly the chips driving those won't be giving the signals. Also the 10.0000 MHz reference oscillator won't be working and everything will be shut down.

 

[kaos513]

You might not need those. If the power supply is not working properly the chips driving those won't be giving the signals. Also the 10.0000 MHz reference oscillator won't be working and everything will be shut down.

I get 10 volts from adapter jack and 10volts to switch bit nothing on that big gray cap So you think the cap is bad ?

 

[Tallman]

I get 10 volts from adapter jack and 10volts to switch bit nothing on that big gray cap So you think the cap is bad ?

Look for a burnt trace, broken wire, or blown fuse. The cap would only used during A.C. power.

 

[kaos513]

Look for a burnt trace, broken wire, or blown fuse. The cap would only used during A.C. power.

Yes even during ac i get no readings on that peaky cap

 

[Tallman]

Yes even during ac i get no readings on that peaky cap

Burnt trace, broken wire, or blown fuse.
The big electrolytic caps very rarely fail to the open condition. What type of test equipment do you have?

 

[kaos513]

Burnt trace, broken wire, or blown fuse.
The big electrolytic caps very rarely fail to the open condition. What type of test equipment do you have?

i used a volt meter, well there some sort of power going through but don't know how far as cap has no juice

 

[kaos513]

Look for a burnt trace, broken wire, or blown fuse. The cap would only used during A.C. power.

 

[Robb]

Think I would check the feed voltage pin on all IC's, after any regulators have been checked for output - first . . .

 

[Tallman]

Take a light and a magnifier and look on the negative side of the capacitor. The photo showed a discoloration on the pcb, or maybe it was just a shadow.

 

[kaos513]

Take a light and a magnifier and look on the negative side of the capacitor. The photo showed a discoloration on the pcb, or maybe it was just a shadow.

 

[Tallman]

Check the power switch?

 

[kaos513]

yes i did with my meter