Large Scale Central

speaker noise/static

How do you filter out the background noise or static picked up by a sound speaker?. I am running a PH hobbies S5100S sound board. It is new. I have the power being picked up from the track with Aristocraft trucks. When the car sits still it is pretty clear sounding, however when it is pulled or pushed it has a static/ noise in the speaker. Is there a way to filter this out and make it clearer sounding. I know this is a old style sound system. but it suits my needs for what I want for now… Thanks.

Does your sound unit have a battery? Many sound units rely on the battery for power when a car is moving and power pickup is erratic.

Dirty track?

Yes it has a battery pack. It is for when the track power is not on and will continue to operate the sound card for about 30-45 sec. after it has stopped. The track is clean. The noise that it reminds you of is like when you turn a radio volume knob that has been sitting for a long time. It will have that staticy noise until it has been turned a few times and it goes away. I was thinking of trying some skates maybe to pick up power, but I would think that the Aristo style axle pick up would be ok…

Travis, is this the same unit you asked about in December 2016?

http://www.largescalecentral.com/forums/topic/26305/ph-hobbies-s5100s-sound

You can filter the power from the track, but these sound systems had lots of quirks… they have been out of business for some time, so perhaps some of the filter caps on the board have gone bad.

Greg

Greg Elmassian said:

Travis, is this the same unit you asked about in December 2016?

http://www.largescalecentral.com/forums/topic/26305/ph-hobbies-s5100s-sound

You can filter the power from the track, but these sound systems had lots of quirks… they have been out of business for some time, so perhaps some of the filter caps on the board have gone bad.

Greg

Yes Greg it is the same one. I finally got around to figuring it out. Can these caps be replaced?. Thanks for the help… Travis.

Probably… I would try some other things first.

So first you say it sounds fine when not moving…

But when it is moving you get static.

Let’s separate movement/increased voltage from track pickups.

So put the loco on it’s back and feed it power to the track pickups, not the wheels… see how it responds as you speed up and down.

This will tell us where the problem lies, just in increased voltage or the track pickup through the wheels.

Remember, you want to apply power to the wires that go to the motor and sound system, NOT the wheels…

Greg

I don’t know this sound system at all but your comments suggest that it runs well on smooth battery power (when static) but not on track power (when moving). I am guessing that your trackpower is PWM and the soundcard does not like it. My suggestion would be to purchase a 35v bi-polar capacitor and connect it across the motor leads which feed the soundcard. That should smooth out the PWM enough so that the soundcard thinks it is running on battery all the time.

If that doesn’t work, you could always buy a MyLocoSound soundcard (which works on PWM) (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-wink.gif)

Regards

Peter Lucas

MyLocoSound

I was going to check for PWM next, but it could be of course.

What MFD value do you suggest?

Greg

We had a similar problem several years ago and used to recommend a 2200uF bi-polar capacitor.

Regards

Peter Lucas

MyLocoSound

Ok, This is a separate car from the locomotive. The sound is powered thru the axles inserts (brass bushing like Aristo) in the journal boxes on the boxcar truck. I am currently using a MRC Control Master 20 with walk around throttle. I have also used the Bridgeworks mini mag3 for power, same results. Hope this describes it better. really would like to use this… The only time the battery pack is in use is when the track power is stopped and the battery keeps the sounds going for about 30 seconds or longer. I have tried it also without the pack and no change…

Here a three pics of my sound car and the inside… I do not have the speaker or battery pack mounted yet, because of needing to eliminate the noise. If the noise cant be fixed then it will all come out…

OK. I will await the results of the test I asked for, we have eliminated PWM as an issue.

Greg

Guys, I appreciate all the input and help… Hopefully a solution can be found… (http://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)

Travis, how about some good hi res shots of the top and bottom of the board?

Also, I see it was steam, perhaps it has a chuff input and the noise you are hearing is it trying to chuff?

Greg

Greg, Here are some photos of the top of the board. I didn’t take any of the bottom as I would have to remove the double sided adhesive tape on it. I do recall tho all it had on the bottom is the circuit patterns. If you do need to see it I will remove it…Hopefully these will help.

Thanks for your help…

I have seen that board, but unfortunately I don’t have the manual for it.

I have the manualso for the S1001, S2001, S3003, and R5005…

This one is set up so you can cut it apart to fit the space.

Unfortunately, PH Hobbies made seemingly dozens of different designs.

Besides the black and white wires tying the 2 halves together at each end, I only see 3 other wires, but I do see a 2 pin connector hanging in the breeze… that should be power… the 3 wires, do they go to the battery, speaker, etc.?

I do see a jumper on the board, could be for chuff.

Many of these early sound boards make “noise” when standing still and the chuff is pretty nasty bursts of white noise.

Can you make a youtube video so we can hear what it sounds like?

I’ll look for a manual on that board…

Greg

Greg, I do not have a youtube acct. but will get you a video of it. The two pin you see with the red and white wires hanging over the top of the boxcar is the power from the truck. i guess I ended up with the odd sound system board.Thanks for your time and help.

Yeah, maybe the picture will help locate someone with the manual. I see jumpers and my guess this static is the chuff circuit…

I see wires on the underside… i assume some are power pickup from the wheels, but it looks as though there is a reed switch to be triggered by a track magnet.

Is there anything on any of the wheels that would/could be a chuff switch? Look for a magnet on a wheel, and a reed switch close by.

Greg

Yes there is a reed switch with a magnet on one wheel. I installed it there. It activates the bell and then the chuff once loco has started moving…