Alternative Volume Control

[dlowrey]

I found this site which has an interesting variation on pachislo/pachinko volume control.

[dlowrey]

I built this tonight using 1/2 watt resistors instead of the 2 watt specified in the instructions.

They only cost me 99 cents, so I figured if I smoked them I wouldn't be out a whole lot.

Well, it works just fine. Went through an entire Big Bonus and they did not get hot at all.

However, as always, your mileage may vary....

[Tulsa]

So doing this mod, while easy enough looks like more work than installing a pot.. Since you've done it, what do you think?

[dlowrey]

So doing this mod, while easy enough looks like more work than installing a pot.. Since you've done it, what do you think?

If you are comfortable soldering, it's no big deal to put together.

I put spade connectors on it, so I didn't have to modify the machine. I just unplugged the wires from the speakers and plugged them into the resistors, then plugged the resistors into the speakers.

It IS kind of ugly looking. A PC board would make it look neater, but would also raise the cost....

[arbycoffee]

it dose put the volumne switch on the machine work better, instead of real loud to loud, to soft to loud.

[huffb01]

I was thinking about building some of these mods up on PC boards, having wires coming out for the connections (so they can be spliced into the speaker wires), adding a dip switch for HI, MED., LOW and BYPASS settings and epoxy coating them so they could be tucked away without shorting....ANY INTEREST??? Right now I have a bunch of parts to use to build and I have to test it. Could this be a product idea for the Tweeters instead of the L-pads or for machines to sell?

[Lddrizzt]

Where is a good place to pick up the resistors? I don't really know much about resistors except that there are a ton of different ones. I don't want to get the wrong ones and screw up something.
The soldering I can do, I just need pointed to the correct parts.

[Tulsa]

Just about everyone has a radio shack near by and they have a bunch.

[dlowrey]

I was thinking about building some of these mods up on PC boards, having wires coming out for the connections (so they can be spliced into the speaker wires), adding a dip switch for HI, MED., LOW and BYPASS settings and epoxy coating them so they could be tucked away without shorting....ANY INTEREST??? Right now I have a bunch of parts to use to build and I have to test it. Could this be a product idea for the Tweeters instead of the L-pads or for machines to sell?

Depends on the price. You can do the L-Pad thing for $4-$5, so it would have to be less than that....

[gwarzin]

Depends on the price. You can do the L-Pad thing for $4-$5, so it would have to be less than that....

The L-Pads I use are $1.95 (plus shipping) from Parts Express. Since these are cheap, readily available, and offer continuous adjustment, I don't see a particular advantage to using the resistors.

http://www.partsexpress.com/pe/showd...number=260-248

[huffb01]

Resistors are available from Digi-Key, Newark or Mouser. I guess I was trying to see if there was a need for an alternative to the L-Pad control. I thought I read post that the L-Pads in certain applications would cause unwanted sounds in piezo tweeters (I might be wrong). I also thought that soldering up a "bunch" of resistors to the speakers inside of a 100+ dollar machine and just waiting for them to touch anything metal inside just seemed kinda scary to me. Plus, using the pots from Radio Shack that are rated for .25 Watts, and do not have much adjustment just doesn't seem the perfect way too. I have not had chance to experiment with L-Pads but if they only have a small adjustment window like the pots, I would think that would be a disadvantage too. Using 2 Watt resistors, dip switches, a PC board and wire, the control should come in about the 5 dollar range in small quantities. I have worked for the past 18 years in contract OEM electronic control PCB manufacturing and have seen companies make patch boards like this. I know I am new to posting to these boards and it takes a while to be "trusted" for an idea or opinion. I am not trying to "cash in" on other peoples ideas, I saw room for improvements and added features and thought I would ask for opinions, THANKS FOR THE RESPONSE!

[Lazarus]

I like the idea of the resisters. Add the extra one and the built in switch will go from almost no sound to just right. I do think that the hole thing should be coated with something to prevent shorts. Any thing I can put on a finished one. Also my local Radio shack does not Cary the resisters needed for this I will have to find a place. Laz.

[arbycoffee]

I don't think anyone was thinking that. They were leting you know what the prices were for different ways. Your idea to make a Gizmo you unplug the wires from the speaker and put it in between is a great Idea for those who don't even own a sodering iron aand would not try it cause it would void their warenty.

I would do up one and figure your cost and mark up, don;t forget the shipping cost and post some pictures and finial cost. You might be well surprised as how many might want some, all those Sammy owners with the Sammy squell.

my 2¢ worth

[arbycoffee]

Use a piece of shrink tubing to protect from shorts

I myself always wear shorts, because of those squicker that leave their Mark :oops: Will this Gizmo help me with Marks ??

[d mowery]

Cotten is cheaper and works great

[Lazarus]

If I remember the tread right you need one resister thing made for each speaker. Will this board handle more than one speaker? it can get costly even at 5.00 a speaker. Laz.

[arbycoffee]

I like your idea because.

My machines, I use cotton balls, because I don't want anything that doesn't look factory, where that done right would look good. My machines are alway for sale at a price, what can I say, If I get someone walk in and want one of the machines I got set up, and we meet on a price, it out of here, I than go to my storage and if I be lucky I get another one an trick it out.
If not go shopping for another one.

Hell this is 3¢ worth

[gwarzin]

I think the resistor ladder "looks" just like an L-pad to the amplifier. So my guess would be that it would have no advantages for use with a piezo tweeter. If you're thinking of a version that works more like a variable resistor, you could still do basically the same thing. But just have your DIP switch take resistors in or out of a series path.

I bet if you thought about it hard enough there'd be a way of designing this so one device could be used either as a resistor ladder, or series resistors depending on which terminals of the circuit board you connected the amp and speakers to. This might take a bit of playing around, because I don't have a clue it the best range of resistance to use would be the same for both applications (piezo tweeters in series, and regular speakers with the ladder).

It might not be worth the effort to figure it all out, given that we do have something that works. Just to recap, here's what I usually do:

If the machines come with volume controls already installed (like Syscom machines) I pretty much just leave them in. (Unless I need to steal a variable resistor - see below.)

If I'm putting volume controls in a pachislo that doesn't already have them, I use an L-pad on regular speakers, and variable resistors on piezo tweeters.

Since I bought a lot of L-pads, if I happen to need a variable resistor for a Sammy tweeter, sometimes I'll take a variable resistor out of a Sycom machine, replacing it with an L-pad. That gives me a little better control over the Syscom and saves me the trouble of buying the small number of variable resistors I'd need.

[d mowery]

I use cotten, when grand son plays the cotten goes in my ears ,Aw yes pease and quite the rest of the day.

[huffb01]

THANKS ALL FOR THE IDEAS!!!!! (wanted to get that out first!)

Laz.---I was thinking about Black Epoxy coating to keep the connections from shorting. (and everyone can keep their own "shorts" to themselves) and yes it would be one assembly per speaker so it would not be as cheap as a pot or cotton.

Arby---Great wisdom on pricing and prototyping...looks like I have some work to do before cutting things loose (I will listen and learn!)

Gary---I think the problem with the piezo tweeters and the L-pads are the fundamental way an L-pad works, (L in L-pad is inductance) and I don't think the piezo likes the variable inductance caused by the L-pad (the L-pad is like a variable transformer that keeps constant load to the Amp and varies the output to the speaker) so by putting the variable resistors on them like you do is the way to go. Do you have much adjustment on the Main speaker adjust with the L-Pads? Are they really touchy? (like you only use maybe a quarter of a turn for all of your adjustment? Syscom uses a 500 ohm pot for their volume adjustment, and I have found that only about 20-50 ohms tops of series resistance is needed to quiet down the main speaker and only about 10 ohms for the piezo tweeters. Again thanks for telling me how you do it so I can learn.

All--- I am not toying with this idea to do it the cheapest (we all know how much cotton we can buy for $5.00) and this is not a "one size fits all" problem solver. I am looking for a modification that is reasonably priced, easy to install, of the best quality and functionality around. I guess I am a purest when it comes to knobs sticking out of machines that were not originally designed in it. BUT I do not want my ears to bleed when I play either!!! I never do anything half-arsed so I would like to try to make this mod. as good as possible and it won't fit everybody's needs. Will all of your input I am well on my way! THANKS AGAIN

Brian