Lost all sound on time pilot

[davieboynj]

My time pilot (restoration thread here: http://forum.arcadecontrols.com/index.php?topic=56692.0) had been out of commission for a while (wasn't taking coins) so today i decided to fix it.  sure enough, there was a ground in the coin switch that had a bad connection.  problem solved, right?

nope.

When i started to play, there was no sound.  - - come to think of it, time pilot has attract sounds  - - It must have been dead for a while, as even when it wasn't being used I still had it powered on from time to time. 

Are there any troubleshooting steps i can perform here?  can anyone point me in the right direction to replace the sound amps?  I'm guessing that's what needs to be done here.   I'm a little out of my depth, but, like Paul McCartney, "I'm gonna try with a little help from my friends..."

I'm tempted to take this "opportunity" to justify picking up Gyruss for testing, as it's the only other game I know that uses the same joystick and pcb wiring.  Doesn't hurt that it's a personal favorite either...   

[SirPeale]

First, check your voltages.  I don't know if Time Pilot requires -5VDC, but a lot of boards require it for sound.  That or +12VDC.

Failing that, the amplifier IC may have blown.  It happens.

[Kevin Mullins]

Just have to ask....

Have you turned the volume up on the pcb?

Attract mode sound can be turned ON or OFF via a dipswitch setting.

[davieboynj]

thx for the replies.  I have messed with the volume knobs on both the board and underneath the control panel, with no effect.  I do get a very quiet scraping sound when moving the one under the control panel, but not as loud as i would expect.  I'm doing all this during gameplay, just in case my memory is shot. 

I'm going to check the voltages with a probe, is there anything more i need do?  I know that sometimes a PC power supply will show voltage, but won't work under load.  I'll post my results...

[davieboynj]

the voltages seem fine..  -5v is only -4.8 but i'd assume that's ok. 

If i have to replace the amps, are there any tutorials for that? 

[RayB]

It's likely a problem with the connection between the 2 boards. Mine will not play sound unless I squeeze the two boards together a bit.

[davieboynj]

do you mean the ribbon cable?  I'll give it a shot...

[davieboynj]

tried it a few times and no luck...  any other ideas?

[Kevin Mullins]

Is the potentiometer in the cab good ?

Is there sound coming off the board but prior to the cabinets potentiometer ?

Could still very well be a sound amp issue, but might as well plug away at the little stuff first.

[davieboynj]

first off,  thanks, all for your help.  I'm sorry i've not been quicker testing things, but i've just been so busy with "real life"^TM lately.  anyways, i bypassed the potentiometer and no luck...  should i check ac voltage on the speaker output, or is it a foregone conclusion that the audio amp is blown?  anyone know how or what parts i need to replace it?  or should i just replace the entire board?

As a side note - - this game is so difficult to play without sound.  I never would have guessed that...