Speed Racer squealing noise from speakers.

[dodc2]

Please help with squealing noise from speakers for an Aristocrat model Speed Racer. I has a high pitch squealing noise from the speakers on the bottom. As I unplug the speakers the noises stop. I also adjust the volume and has no effect on the noise


Thanks for your help.

[gwarzin]

Lot's of pachislos (especially those with video) squeal. In your case the good news is that changing the volume does not change the squeal. That means that the squeal is entering the system at the amplifier, and not at the speakers.

So, install L-pads between the amplifier and speakers. Turn UP the volume at the amplifier and then reduce it to a normal level using the L-pads. The squeal will drop in level along with the normal sounds - hopefully to an acceptable level.

Do a search in this forum and volume control or L-pad and you should find lots of messages dealing with this issue. Might even be something in the FAQ.

[cwstnsko]

In my experience, Aristocrat = Sammy = squeal. A gwarzin stated above, volume mods should take care of it. On my Aristocrat machine I am running a 15W stereo L-Pad and fixed resistors at the speakers. This machine with just the L-pad had very little useful range in adjusting the volume.

[TANK]

has anyone tried a noise supressor in line from the pwr supply? i don't have this problem on any of my machines but would bet it's probably coming from the pwr supply. check with a stereo supply co. most noise suppressors will handle up to 36 volts with no problem. we use them all the time on military vehicles (24volts) to get rid of the noise on the radios.

[arbycoffee]

Sir Tank,

Post some linc.s if you would, it would be helpful.

[gwarzin]

has anyone tried a noise supressor in line from the pwr supply?

The machine I had the worst problems with was Thunderbirds. Here the problem was caused by the video display. I could cut power to it and the rest of the machine was dead silent. Power up the video and there was lots of noise coming through the speakers.

I did try ferrite cores on some of the power supply lines (and other wires as well) and they made no difference. In the end I assumed it must be airborne and getting back from the video to the amplifier. So I gave up and just went the L-pad route.

[Tulsa]

I've always wondered if it was a ground loop issue and an ground loop isolator would take care of it?

http://www.radioshack.com/product.as...t%5Fid=270-054

[vgc]

Along with the High Speaker Squeal when on, I also have a Low Humm probably coming from the Power Source when Turned off. I have 2 Speed Racers and both have the same Squeal & Humm. These are the only 2 Machines I unplug when not playing. My other dont make a sound when turned off and Plugged in ? I just ordered 10 sets of Double Volume Controls from Stealth Today along with a Wanted by NET Machine. Thanks for the Pachitalk Discount. Yea ! Mike : )

[vgc]

Dah, looks like I am talking to myself here. I do this from time to time in real life. Anyway I did the Volume Controls on the 2 speakers of my Speed Racer and it worked perfectly. The job only took like 15 min., and that because I was using a blade as a wire stripper. 1 question on a side note. Should these machines be unplugged when not being used, as I stated before I get a soft humm when plugged in but not turned on ? Mike : )

Todays Additions : Beast Sapp, HH & Ryugo. Yeeeehawww !!

[Tulsa]

The humm is the transformer. I would put them on a power strip myself. It makes for an easier switch to get to and you remove all power when not in use. Ultimately the transformer will last longer when it's not constantly being heated by electricity.

[vgc]

Easy Fix. Done ! Thanks. Mike : )