Service Manual, Parts List, PCB or CD diagram of the Yamaha HH65 pedal

[shr1]

Dear Frens,

I need to know what pressure sensor the Yamaha HH65 pedal uses and how it is connected to the jack socket. So can you help me by uploading the Service Manual, Parts List, PCB or CD diagram of the Yamaha HH65 pedal if you have it?

 

[keith1200rs]

The pedal schematic is attached. It uses a conductive rubber switch which progressively shorts out the resistors. The capacitor/diode are to do with the "splash" I believe. As far as I recall the DD50 uses simple switches.

Keith

 

[shr1]

Thanks a lot, Keith! Do you also know the part number of the conductive rubber switch?

 

[shr1]

"I need to know the way the pedal is supposed to work which is not clear from this drawing. The connection to the rubber part that touches the contacts, if there is any connection to it, is not shown.

I'm assuming that one of the cable conductors is a power supply, and the other is a signal which represents the pedal pressure, either as a voltage or perhaps as a resistance. But this is not clear to me from the circuit diagram of the pedal."

- originally from Kris

 

[keith1200rs]

There are some picures of the inside of the HH65 here: https://groups.yahoo.com/group/DTXpress/photos/album/1605268992/pic/list

One of the pictures shows a white rectangle of insulating material which covers the "switches". It consists of a flexible, conductive membrane (a bit like a flexible PCB) which is pushed onto the PCB underneath and so shorts connections out. It wires into the PCB with the resistors/capacitor/diode on it.

I think the pedal rubber is connected to ground. When you push the pedal down it first shorts out R2 then R3 etc. When it reaches the end the only resistance is R5 from the tip of the jack to ground.

There is no power supply. The Yamaha module senses the resistance by applying a voltage to the tip (through a resistor or possibly with a current source).

Keith

 

[alex72]

@Keith

I am getting no response with this pedal. I took apart the pedal and separated the flexible, conductive membrane from the component bored. I think the flexible membrane is the issue, but I haven't checked each 4 contacts from the lead to ground with a multimeter yet. Do you know where I can find a replacement flexible membrane? I would much appreciate the help.

 

[keith1200rs]

I doubt you will be able to buy just the flexible membrane, but possibly the PCB through Yamaha.

I fixed someone's hihat pedal once by peeling the membrane off and sticking it back down again. I think it had become permanently deformed but doing that seemed to give it a new lease of life. I don't know how long it lasted though.

Keith

 

[alex72]

Thanks Keith, I will give that a try and let you know if it is a success.

- - - Updated - - -

The flex membrane seems to be fine. I will check the circuit board components tomorrow with a multimeter. Hopefully it's just a bad resistor

 

[BradtheRad]

Can you confirm whether the cable is sound internally and where it connects to the PCB? It's a typical trouble spot.

I have a Yamaha keyboard with a foot-pedal which contains a switch and that's all. It gets kicked around a bit. The cable goes into the housing, then winds around a post which serves as an anchor. Several times the cable has broken internally. The location is usually at the point where it winds around the post.

The break is invisible to the eye, until I unsolder the end, and pull on the wire end. Out comes a length of bare stranded wire. Usually it's two inches long.

I cut away insulation back to where the break occurred, and re-solder the wires.