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Need help with a hammond B3 project idea.

Thread starter #1
Hi all
I was wondering if anyone could help me I work with a band as an organ tech we have a beast of a Hammond b-3 player and I've done a little work on his expression pedal by adding a remote switch for changing the speeds of our Leslie speaker system.
I would like to install some LEDs inside the pedal that would change color with changing the speed of the spinning Leslie which is accomplished by taking on the toe switch I have installed.
Line voltage 120 volts goes through this ittle switch I'd like to know how I can have LEDs glow red when the switch is off (with no voltage to this circuit inside the Leslie the slow speed motors are on and the Leslie is spinning slowly) and green when the switch is on (and the far speed motors are getting voltage and the Leslie speakers are spinning fast) inside the Leslie when the switch is off the speakers spin slowly and inside the Leslie when the switch is on the speaker spins fast.
. I am using LED strip lights around six inches long with the LED every inch or so powered either by a 9 volt battery or a phone charger for lighting 5 volts which I think is probably more suitable.
Here is a link to a YouTube video which tells you everything you need to know about a Leslie they're really cool.
. And here's a couple of pictures of another toe switch I installed on different expression pedal already.
.I know I can do this with a relay but I can't really find one small enough and electricly quiet enough. I was hoping there was a more elegant solid state solution that would be physically smaller and I'd be able to fit it in the space I have under the pedal.
Thanks so much I look forward to hearing from someone.
PHOTO_20180915_173955.jpg

PHOTO_20180915_174033.jpg
 

dr pepper

Well-Known Member
Most Helpful Member
#2
The idea shouts for a microcontroller, but that requires programming skills.
If your not into programming try googling Lm3914, its a bargraph driver chip that switches Led's according to an input voltage, using diodes you might be able to switch Rgb Led's in a colour sequence.The voltage for the driver chip could come from a pot piggy backed to the original in the pedal, if it has one.
 

eTech

Active Member
#3
Hmmm....seems a FTV convertor would be a good fit for this. Maybe as a front end to an LM3914 or some other level detection circuit. It would need a speed sensor attached to the rotating Leslie somehow..

FTV could be LM2907 or other.
 

granddad

Active Member
#4
Thanks Jeff Had to watch the Leslie video.. but it got sort of stuck at the end.. electronics and music go well together .. not sure about flashing leds ..
 

dr pepper

Well-Known Member
Most Helpful Member
#5
Tacho chip is a god idea.
A 4017 is a cmos chip that steps one of 10 outputs on each clock pulse, it could be used to do something also.
 

eTech

Active Member
#6
Line voltage 120 volts goes through this little switch I'd like to know how I can have LEDs glow red when the switch is off (with no voltage to this circuit inside the Leslie the slow speed motors are on and the Leslie is spinning slowly) and green when the switch is on (and the far speed motors are getting voltage and the Leslie speakers are spinning fast) inside the Leslie when the switch is off the speakers spin slowly and inside the Leslie when the switch is on the speaker spins fast.
After reading post #1 again, I think the TS wants the to mount the LED strip on the foot pedal and have it light Red for slow rotation, and Green for fast rotation. So it will light more of a "step" fashion. But we need clarification.

eT
 

eTech

Active Member
#7
Hi all
I was wondering if anyone could help me I work with a band as an organ tech we have a beast of a Hammond b-3 player and I've done a little work on his expression pedal by adding a remote switch for changing the speeds of our Leslie speaker system.
I would like to install some LEDs inside the pedal that would change color with changing the speed of the spinning Leslie which is accomplished by taking on the toe switch I have installed.
Line voltage 120 volts goes through this ittle switch I'd like to know how I can have LEDs glow red when the switch is off (with no voltage to this circuit inside the Leslie the slow speed motors are on and the Leslie is spinning slowly) and green when the switch is on (and the far speed motors are getting voltage and the Leslie speakers are spinning fast) inside the Leslie when the switch is off the speakers spin slowly and inside the Leslie when the switch is on the speaker spins fast.
. I am using LED strip lights around six inches long with the LED every inch or so powered either by a 9 volt battery or a phone charger for lighting 5 volts which I think is probably more suitable.
Here is a link to a YouTube video which tells you everything you need to know about a Leslie they're really cool.
. And here's a couple of pictures of another toe switch I installed on different expression pedal already.
.I know I can do this with a relay but I can't really find one small enough and electricly quiet enough. I was hoping there was a more elegant solid state solution that would be physically smaller and I'd be able to fit it in the space I have under the pedal.
Thanks so much I look forward to hearing from someone.
View attachment 115590

View attachment 115591
Hi

Do you have a schematic of the foot switch and the foot switch power sources?
A part number for the LED strip would be helpful also.

eT
 
Thread starter #8
Yes that is what I'd like to accomplish. Mount the two LED strips on the foot pedal and have the Red ligtup for slow rotation, and Green for fast rotation. The foot (actually a toe) switch is a simple spst soft touch latching push button. The LEDs strips are labeled 6v-12v 26LSM1 that's the red strip number I don't have the green with me. I am an electrician by trade and thought a relay would do it but as I said I know there is a way more compact and smarter more elegant solution here I really do not understand electronic circuits at all but I did recently buy a beginner Arduino kit and plan on getting started with that soon. This pedal project is on a fast track tho and so I appreciate any and all help you all can give me. Sorry for my lagging response it's been a exrra hectic week Thanks!
 

dr pepper

Well-Known Member
Most Helpful Member
#9
If you replace the footswitch for another with an extra set of contacts, a double or quad pole switch, just use one of the poles to switch + from red to green.
The arduino can do fancy stuff inbetween when you get handy with it.
 

eTech

Active Member
#10
Yes that is what I'd like to accomplish. Mount the two LED strips on the foot pedal and have the Red ligtup for slow rotation, and Green for fast rotation. The foot (actually a toe) switch is a simple spst soft touch latching push button. The LEDs strips are labeled 6v-12v 26LSM1 that's the red strip number I don't have the green with me. I am an electrician by trade and thought a relay would do it but as I said I know there is a way more compact and smarter more elegant solution here I really do not understand electronic circuits at all but I did recently buy a beginner Arduino kit and plan on getting started with that soon. This pedal project is on a fast track tho and so I appreciate any and all help you all can give me. Sorry for my lagging response it's been a exrra hectic week Thanks!
Hi

Is it possible to replace the spst switch with a dpdt switch? So we don't have to disturb the function of the existing contact?
We will need spec on LED strip, preferably a mfg data sheet.
Is it possible to fit a 6 to 12 battery in the pedal? As an alternative, a 12vdc wall wart jack to power the circuit?
What power source voltages exist in the pedal?

A pedal schematic would help..

eT
 
Thread starter #11
I can't replace the switch. I tracked it down and apparently it is an old radio shack"soft touch" sp latching push button. The soft touch is the important thing here as it is actuated by a subtle"push" with the players toe as he is moving the pedal up and down while playing, I've searched for another push button with the soft touch designation but couldn't find one suitable. Anyone know of something that fills the bill. Can I just wire a parallel set on contacts to create a dpdt switch. I can't think of a way to do that and keep the two sets of contacts isolated from each other. But yes certainly if u could somehow get another set of contacts or two even I could wire a simple circuit for each of the two colors. Yes a wall wart is called for here to power some LEDs that will glow BRIGHTLY it is going to look great but really the idea is for my organ player to be able to look down and know if the Leslie is spinning fast or slow before he pressed a key. Tonight I used the new pedal that I made for the first time and it worked fine I'll attach a picture. I want to put the LEDs under the metal that is mounted on top of the brass stantions. The led strip that I used was disappointing brightness wise but still looked cool. A red glow under the pedal is a subtle but fun look and when I get this figured out I think it will be helpful to my player and look great even if no one really knows it but the few people standing near it. I like my devices to look great as we'll as do there job. The little enclosure I made for the push button is cocobolo wood with s Mosaic metal pin embedded. See the close up of the switch. My soldering skills are sorely lacking. I need to invest in a quality iron for sure.
Thanks again I hope someone will provide the idea or part I'm looking for to accomplish this relatively simple device mod.
 

Attachments

dr pepper

Well-Known Member
Most Helpful Member
#12
If you cant find a switch with enough poles, use the original switch to fire a relay with 2 or more poles, use one for the original speaker control & the others for your Led's.
 
Thread starter #13
Again I apologise for my lagging reply. Yes I think that's the answer until I learn enough to use electronic components to get it done. I need to find a high quality, and most importantly A QUIET relay that won't introduce a click into the sound as it switches. Again a problem I know has an answer in electronics. But for now a small reliable relay with a120 volt coil and 4 sets of contacts 2no 2nc should do the trick. Happy hunting to me!
And THANK YOU to everyone here. I truly appreciate your help.
Peace
Sparky
 
Thread starter #14
Hi everyone and Happy New Year
I think I came up with a way to accomplish what I've been trying to do. It would use one of these to (see attached photo) to step down the line voltage going through the switch to 5 volts using a 5volt to power relay. The relay would get 5 volts to the coil when the switch was active or closed and the normally open contact would close turning on the green lights when the Leslie was spinning fast then when the switch is opens the coil would not get the five volts and the normally closed contacts would close turning on the red LEDs lights . The leds will be powered separately and sized appropriately to the relay specs and LEDs I use. Any thoughts? Any suggestions on the relay? All of the 5 volt relays I see use some sort of trigger signal that causes the state change not just the powering or not of the coil. That is confusing to me. I look forward to your feedback and thank you very much. I also saw some ssr that may work the input being 120volts which then puts it 5 volts our 12 or whatever you choose to power the LEDs but I think I'm missing something there hmmm? Screenshot_20190108-134026.png
 

eTech

Active Member
#15
That image looks like a switching power supply. I'd be concerned with noise being induced into the audio.
You should use a small linear supply. Maybe a couple small 120VAC o 5/12VDC wall warts with just enough current to light each led strip. Also, if additional 120v wiring is routed in the pedal, it would need to be done safely.

eT
 
#16
Last edited:

dr pepper

Well-Known Member
Most Helpful Member
#17
If you want to make sure the relay coil remains 'quiet'.
Put a 1n4001 diode across the relay coil, with the cathode (silver stripe) on the diode to the positive side, orientation here is important.
Then place a 100nF x7r or similar capacitor in series with a 100 ohm 1/4 watt resistor in series across the coil, orientation is not important.
This should make clicks go away, its also a good idea to have the power for the relay coil to be on a seperate cable, if you run the relay coil signal in a screened cable along with audio you heading for clunks & clicks.
 
Thread starter #18
That image looks like a switching power supply. I'd be concerned with noise being induced into the audio.
You should use a small linear supply. Maybe a couple small 120VAC o 5/12VDC wall warts with just enough current to light each led strip. Also, if additional 120v wiring is routed in the pedal, it would need to be done safely.

eT
Thanks for your reply and ideas I am obviously very much in the deep end of the pool and I must confess to not understanding much of the replies to my latest post. But I'll just ask the questions and maybe together we can work this out. To your reply quoted above I ask this...
If I use wall warts to power the LEDs what did you Invision in terms of the device/component that would switch them. Keeping in mind that I'm trying to let the player look down and by seeing either a red glow from LEDs (when the Leslie is spinning slowly and therefore no voltage present at the switch) or a green glow when the Leslie is spinning fast, voltage.... Wait as I wrote this it occurres to me that voltage is present at the switch in either state it's just current that is flowing or not... Just a thought. Back to the problem what do you suggest I use to trigger or power the coil in the relay. Or is there another device or type of relay I could use.
I never anticipated this being easy but also never thought it would be as complex as it is seeming.
I am an electrician and appreciate your comment on care being used when routing 120volts at the pedal.
If I'm looking in the wrong direction due to my ignorance of electronics I'm open to any ideas using any components out there to accomplish this. I just hope I understand anyone's suggestions so that I can implement them.
This is fun and I thank you all
 

dr pepper

Well-Known Member
Most Helpful Member
#19
I can answer the red/green Led issue, use a change over contact within the relay, normally closed to red, normally open to green, and common to + supply.
 
Thread starter #20
[/QUOTE="MichaelaJoy, post: 1343219, member: 281285"]

Also, take a look at this.

https://www.onsemi.com/pub/Collateral/AN-3001.pdf.pdf

The idea is to use a bridge rectifier and filter for each switch. The output of the optoisolator can be used to drive leds.

I had a friend who played a Hammond Porta-B with a Leslie Tone Top.
It's what got me into playing keyboards. :)[/QUOTE]
Whoa that PDF is very interesting but way over my head I think I'm rereading it again but I can't help but be reminded that at one time the B3 expression pedal used a optical resister or I think that what it was called. It was an actual small lamp and a photo sensitive gizmo with a divider between then that had slit in it that widened as it moved down with the pedal our vice versa. I have one out in my shop but can't find a picture. The closest I could find is the replacement lamp that is soon being sold for today that need it and the info on that I'll paste it here ”Expression pedal lamp for Hammond E-100/200/300, H-100/200/300, L-100 and Porta-B series organs. Replaces Hammond part number 016-031748. Failure of this lamp will cause the organ to operate at full volume regardless of expression pedal position”
 

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