Disclaimer: This information is provided as is. There may be errors in this information. You may use this information only if you agree that Minimalist / Coinop.org, its employees, and noted authors will never be held responsible for any damage, injury, death, mayhem, etc. caused by errors in the information. When working with high voltage, never work alone and always follow safety precautions.

Document Title: [ScrambleFroggerTurtlesSnd.txt (text file)]

Subject: TECH: Tips for Sound problems on Scramble, Frogger, Turtles.
From: *pcjohn@monmouth.com (John Dondzila)
Date: Fri, 18 Sep 1998 00:12:00 GMT

These boards are all more or less the same. I've seen
numerous requests over the last few years for sound
help on these boards with no answers. My Turtles
sound crapped out tonight, so let me share my notes ...

(1) Check that the board is getting 12 volts.
  (Make sure the connector is clean ! Use a pencil eraser to remove crud)

(2) Check that the board is getting -5 volts.
  (Make sure the connector is clean ! Use a pencil eraser to remove crud)

(3) If voltages are good, turn up the volume all the way. The speaker should at
least hum, buzz or hiss. If no, check your speaker and speaker wire connections.
If good, then your amplifier chip is probably bad.

(4) If you get some hum, buzz or hiss, check the 5 volts on the board. Check
it at the ICs, not at the power supply. This was the problem on my board. If
it's too low, the audio circuitry will crap out before the game logic. Too high
and the first thing you'll get is sprite problems. My board has to be set at
5 volts exactly.

(5) Voltage ok ? Near the amplifier chip, find the little 8 pin LM741 IC and
replace it. There are 2 sound chips on the game and both go through this op-amp.
If the op-amp is bad, you'll get nothing.

There are also a few caps near the amplifier. These could possibly go bad, but I
think the most likely culprits are those outlined above.

Hope this saves some boards from the dumpster !

Anti SPAM In Use !
Remove the * from *pcjohn@monmouth.com
to send E-Mail.}