Build Your Own Arcade Controls Forum

Main => Monitor/Video Forum => Topic started by: Arm123 on May 30, 2008, 02:07:15 am

Title: AM-0316 schimatic
Post by: Arm123 on May 30, 2008, 02:07:15 am

I have this chassis sitting here, with a burnt R91 and cant make out the color code.

here is a pic of the chassis, its the same...

http://arcadecontrols.com/BBBB/am.html

Anyone know what the value of R91 is ?

Title: Re: AM-0316 schimatic
Post by: Ken Layton on June 03, 2008, 06:05:10 pm

Might be a 2.2 ohm 2 watt flameproof. Generally if this resistor burns it's because the vertical output IC is shorted. So replace the vertical output IC and the resistor both.

Title: Re: AM-0316 schimatic
Post by: Arm123 on June 03, 2008, 11:44:40 pm

Thanks alot Ken.

Inititally i 'tried' to read the burnt colors off the resistor.  I got ether 1.3 / 1.3k and I decided to try the 1.3.

The CRT sounded like it powered up, but i saw no neck glow.  I left it on for a bit and then heard sounds like it was struggling to sync.  Still no picture.

Unplugged and checked la7831, GND (pin 3) was shorted to Vertical out (pin 4). Another $7 gone ;-P

Also checked the diode that was between the burnt resistor and the Vcc terminal pin 6 of LA7831 and its shot as well.

Ill have to get a 2.2 ohm 2 watt flameproof and new diode.  I hope this does the trick.