Re: Replacing bulb on Yamaha CS-80 expression pedal?
Martin:
For PH1, PH2, and PH3 on the PRA board, the Xvive Vactrol VTL5C3 is a drop-in replacement.
Its response curve?is the same as original working parts on the PRA card according to my tests and I have used?them on several occasions to restore function to CS-80's without issues. I keep them in the parts bins for the occasion when a customer's machine shows up with a dead?one.
Scott Rodriguez
Hi Martin, how told that was Mr. Scott Rodriguez, I only agreed
with his comment.
Anyway let me tell you that if the Diode that illuminates the photo
resistor in PH1, PH2 or PH3 opens up, that is going to make that you
do not get sound from the CS. This is because of the topology of the
circuit (devices are in a serie).
Regarding a replacement, since I didn't have problems with them, I
do not know. But I can give you some ideas.
On one hand you can try to look for an integrated device (how I
suppose that PH1, PH2 and PH3 are). The main characteristic must be
the resistance of the photo resistor with the lower and higher
light..... I have seen in t he past.... long, long time ago, that
sometime these devices are custom made. On one hand you have the
photocell and lamp and a tube keeping the lamp facing the photocell,
usually kept all together
by mean of termocontraible tube. Photocells of a given size have
likely response (this is not absolutely true, but we can approach
the point this way). Replacing the old lamp with a LED is something
that deserve a analysis and trial-error procedure.... They do not
have for sure a likely response regarding Voltage applied versus
lighting power. Anyway there is something to keep in mind, to avoid
problems of a misbehavior, replace all the PHx at once. Depending of
the lighting device chosen, you surely will have to make an
adjustment to the variable voltage that feeds the lamps.
Hope these thoughts can help.
Have a nice day/night!
Gustavo.
On 9/4/2022 7:05 PM, Mooseheads wrote:
Greetings
to all,
?
Since
the topic is including problems on the PRA board (which mine
has) I thought I
would ask.? Gustavo when you write:
?
“If
one or both of the sensors in the CS-80 are dead,
replacements are available.
I'm not familiar with the…”
?
Are
you by any change referring to PH1, PH2 and PH3 on the PRA
board?? I have been looking for a replacement part
for some time.? Would you mind letting me
know what that replacement part is?? This
is the last issue I am aware off in my machine, I would very
much like to rectify
the problem!
?
?
Thank
you very much
?
?
Martin
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hi Martin, how told that was Mr. Scott Rodriguez, I only agreed
with his comment.
Anyway let me tell you that if the Diode that illuminates the photo
resistor in PH1, PH2 or PH3 opens up, that is going to make that you
do not get sound from the CS. This is because of the topology of the
circuit (devices are in a serie).
Regarding a replacement, since I didn't have problems with them, I
do not know. But I can give you some ideas.
On one hand you can try to look for an integrated device (how I
suppose that PH1, PH2 and PH3 are). The main characteristic must be
the resistance of the photo resistor with the lower and higher
light..... I have seen in t he past.... long, long time ago, that
sometime these devices are custom made. On one hand you have the
photocell and lamp and a tube keeping the lamp facing the photocell,
usually kept all together
by mean of termocontraible tube. Photocells of a given size have
likely response (this is not absolutely true, but we can approach
the point this way). Replacing the old lamp with a LED is something
that deserve a analysis and trial-error procedure.... They do not
have for sure a likely response regarding Voltage applied versus
lighting power. Anyway there is something to keep in mind, to avoid
problems of a misbehavior, replace all the PHx at once. Depending of
the lighting device chosen, you surely will have to make an
adjustment to the variable voltage that feeds the lamps.
Hope these thoughts can help.
Have a nice day/night!
Gustavo.
On 9/4/2022 7:05 PM, Mooseheads wrote:
toggle quoted message
Show quoted text
Greetings
to all,
?
Since
the topic is including problems on the PRA board (which mine
has) I thought I
would ask.? Gustavo when you write:
?
“If
one or both of the sensors in the CS-80 are dead,
replacements are available.
I'm not familiar with the…”
?
Are
you by any change referring to PH1, PH2 and PH3 on the PRA
board?? I have been looking for a replacement part
for some time.? Would you mind letting me
know what that replacement part is?? This
is the last issue I am aware off in my machine, I would very
much like to rectify
the problem!
?
?
Thank
you very much
?
?
Martin
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Greetings
to all, ? Since
the topic is including problems on the PRA board (which mine has) I thought I
would ask.? Gustavo when you write: ? “If
one or both of the sensors in the CS-80 are dead, replacements are available.
I'm not familiar with the…” ? Are
you by any change referring to PH1, PH2 and PH3 on the PRA board?? I have been looking for a replacement part
for some time.? Would you mind letting me
know what that replacement part is?? This
is the last issue I am aware off in my machine, I would very much like to rectify
the problem! ? ? Thank
you very much ? ? Martin
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hi,
Could anyone provide the correct style/base number for the?24v 5w bulb in this expression pedal? It seems like most of the 24V 5W are huge. Many indicator lamps have a standard four digit number like #1819 etc. or a letter and number code in the EU.
And is it the same as is used in the touch sensor strip in a CS-50?
I already accidentally bought a box of huge ones :(
Thanks,
DT
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Gustavo.:?I was trying to assist??Mathias with his debugging efforts. And right you are, the preamp card is called out as PRA, not PRE, my mistake.
Hello Scott, I do not know if you are adressing to Mathias or
me....
Just in case it is me, I have the original Foot Controller with
Lamp/Photoresistor. and the board that you referenced it is PRA
board and what you say it is correct. That board basically let you
control 2 signals (Stereo output) with a single control (Foot
Controller).
Have a nice day!,
Gustavo.
On 9/4/2022 8:27 AM, Scott Rodriguez
wrote:
Do you have a Yamaha FC7 expression pedal you
could use to check out the circuit? They work ok with the
CS-80, but the range is a bit biased compared to the original
light-operated unit. That will at least tell you if the sensor
in the pedal is dead, or if the sensors in the CS-80 are dead.
Also be aware there are two independent sensor circuits on the
CS-80 PRE card, one for the Left output and one for the Right
output. So, try the Left and Right output jacks independently
using a known-good pedal (like an FC-7).to determine if the
sensors in the CS-80 are bad.? Be advised the sensors can
"sort of" work and pass just a little bit of?signal. You may
be able to hear just a little bit of output from one side and
none or a little more from the other. They can pass all of the
signal,?none of it, or anywhere in between.
If one or both of the sensors in the CS-80 are dead,
replacements are available. I'm not familiar with the pedal
sensor as I've never had one to work on. I expect a properly
spec'ed?replacement would be available for it as well. It's
probably the same as a CS-50/60 aftertouch sensor, but that's
just a guess.
Hello Mathias, in a couple of weeks I will be at the
place where it is stored my CS-80.
Then I will be able to take note of the Foot Controller
circuit and pass you some information to verify yours.
Hold on.
Have a nice weekend!,
Gustavo.
On 9/3/2022 6:08 AM, Mathias Tjonn wrote:
Hi Gustavo,
?
Thank you for the information! I did open up the pedal
and good news: the bulb is working when plugged in and
gives off light.
I don't know how to test the photo-resistor, however.
Any help appreciated!
...or if the fact that the pedal is not working, means
there is something wrong with the CS-80?
?
Any further thoughts much appreciated. Best, Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hello Scott, I do not know if you are adressing to Mathias or
me....
Just in case it is me, I have the original Foot Controller with
Lamp/Photoresistor. and the board that you referenced it is PRA
board and what you say it is correct. That board basically let you
control 2 signals (Stereo output) with a single control (Foot
Controller).
Have a nice day!,
Gustavo.
On 9/4/2022 8:27 AM, Scott Rodriguez
wrote:
toggle quoted message
Show quoted text
Do you have a Yamaha FC7 expression pedal you
could use to check out the circuit? They work ok with the
CS-80, but the range is a bit biased compared to the original
light-operated unit. That will at least tell you if the sensor
in the pedal is dead, or if the sensors in the CS-80 are dead.
Also be aware there are two independent sensor circuits on the
CS-80 PRE card, one for the Left output and one for the Right
output. So, try the Left and Right output jacks independently
using a known-good pedal (like an FC-7).to determine if the
sensors in the CS-80 are bad.? Be advised the sensors can
"sort of" work and pass just a little bit of?signal. You may
be able to hear just a little bit of output from one side and
none or a little more from the other. They can pass all of the
signal,?none of it, or anywhere in between.
If one or both of the sensors in the CS-80 are dead,
replacements are available. I'm not familiar with the pedal
sensor as I've never had one to work on. I expect a properly
spec'ed?replacement would be available for it as well. It's
probably the same as a CS-50/60 aftertouch sensor, but that's
just a guess.
Hello Mathias, in a couple of weeks I will be at the
place where it is stored my CS-80.
Then I will be able to take note of the Foot Controller
circuit and pass you some information to verify yours.
Hold on.
Have a nice weekend!,
Gustavo.
On 9/3/2022 6:08 AM, Mathias Tjonn wrote:
Hi Gustavo,
?
Thank you for the information! I did open up the pedal
and good news: the bulb is working when plugged in and
gives off light.
I don't know how to test the photo-resistor, however.
Any help appreciated!
...or if the fact that the pedal is not working, means
there is something wrong with the CS-80?
?
Any further thoughts much appreciated. Best, Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Do you have a Yamaha FC7 expression pedal you could use to check out the circuit? They work ok with the CS-80, but the range is a bit biased compared to the original light-operated unit. That will at least tell you if the sensor in the pedal is dead, or if the sensors in the CS-80 are dead.
Also be aware there are two independent sensor circuits on the CS-80 PRE card, one for the Left output and one for the Right output. So, try the Left and Right output jacks independently using a known-good pedal (like an FC-7).to determine if the sensors in the CS-80 are bad.? Be advised the sensors can "sort of" work and pass just a little bit of?signal. You may be able to hear just a little bit of output from one side and none or a little more from the other. They can pass all of the signal,?none of it, or anywhere in between.
If one or both of the sensors in the CS-80 are dead, replacements are available. I'm not familiar with the pedal sensor as I've never had one to work on. I expect a properly spec'ed?replacement would be available for it as well. It's probably the same as a CS-50/60 aftertouch sensor, but that's just a guess.
Hello Mathias, in a couple of weeks I will be at the place where
it is stored my CS-80.
Then I will be able to take note of the Foot Controller circuit
and pass you some information to verify yours.
Hold on.
Have a nice weekend!,
Gustavo.
On 9/3/2022 6:08 AM, Mathias Tjonn
wrote:
Hi Gustavo,
?
Thank you for the information! I did open up the pedal and good
news: the bulb is working when plugged in and gives off light.
I don't know how to test the photo-resistor, however. Any help
appreciated!
...or if the fact that the pedal is not working, means there is
something wrong with the CS-80?
?
Any further thoughts much appreciated. Best, Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hello Mathias, in a couple of weeks I will be at the place where
it is stored my CS-80.
Then I will be able to take note of the Foot Controller circuit
and pass you some information to verify yours.
Hold on.
Have a nice weekend!,
Gustavo.
On 9/3/2022 6:08 AM, Mathias Tjonn
wrote:
toggle quoted message
Show quoted text
Hi Gustavo,
?
Thank you for the information! I did open up the pedal and good
news: the bulb is working when plugged in and gives off light.
I don't know how to test the photo-resistor, however. Any help
appreciated!
...or if the fact that the pedal is not working, means there is
something wrong with the CS-80?
?
Any further thoughts much appreciated. Best, Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hi Gustavo,
?
Thank you for the information! I did open up the pedal and good news: the bulb is working when plugged in and gives off light.
I don't know how to test the photo-resistor, however. Any help appreciated!
...or if the fact that the pedal is not working, means there is something wrong with the CS-80?
?
Any further thoughts much appreciated. Best, Mathias
|
Thanks David, this was amazing!
?
Best, Mathias
|
Hi all!
I ran across this Led Zeppelin video last night about In Through The Out Door. It has a surprising amount about the wonderful Dream Machine including the ELP and Abba connections. This link should jump right to where they start talking about it. Enjoy!
David
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
No problem Some else wants it.? It will be good see ?it get used.? Best of luck solving your problem.?
?
Hi Stan,
Thank you kindly for the offer, but since I just bought an original pedal, I'd like to find out if the problem lies with it or with my CS-80 (if not, even if I buy your pedal, the issue would remain). Appreciate the offer, though!
Anyone here have any hands-on experience with taking these pedals apart and attempting to fix them?
All my best,
Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hello Mathias,
I do not have had to deal with problems in my expression pedal,
but I have some ideas how it works (I'm a tech guy) I would lend
you a hand.
The mechanism has 3 parts.
1.- A lighting device (the bulb)
2.- A Light obstruction mechanism
3.- A photo resistor cell
The plug has 3 terminals. One is common, the other is the lamp
power source and the last is the variable resistance that modify
the volume.
If you do not see a light even in the pedal assembled, there is
something wrong, lamp or power.
If you open the pedal you will have the chance to check what is
wrong and more important make a further test.
Even if the power source of the lamp is wrong, you can allocate a
lighting device in the neighborhood of the lamp, and if move the
volume control, you will notice that it works (if everything is OK
inside the CS-80).
I do not know how skilled in electronics are you to go ahead, let
me know.
Let me tell you that I do have a CS-80 and both original pedals.
I got it in bad electronics condition from the official support of
the brand (the unit was a demo unit, never sold that fail and
could not was possible for them repair it). I could do it... it
happened about 30 years ago.
Have a nice? day!,
Gustavo.
On 2022-08-17 7:43 PM, Mathias Tjonn
wrote:
toggle quoted message
Show quoted text
Greetings fellow synth travelers,
?
So, I finally found an original expression pedal for my CS-80
after many years of searching...and it doesn't work. I
understand there's a 24v5w bulb in there and thought perhaps it
has burned out, anyone here have any experience opening these
pedals up and replacing the bulb?
Any hints and help greatly appreciated!
Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hi Stan,
Thank you kindly for the offer, but since I just bought an original pedal, I'd like to find out if the problem lies with it or with my CS-80 (if not, even if I buy your pedal, the issue would remain). Appreciate the offer, though!
Anyone here have any hands-on experience with taking these pedals apart and attempting to fix them?
All my best,
Mathias
|
Re: Replacing bulb on Yamaha CS-80 expression pedal?
Hi,
?
I have a pedal I am not using. ?I sold my CS80and found it later.? I you are interested let me know.? I would like to get $200.00.? That’s what I paid for it about 10 years ago.?
Stan
?
Greetings fellow synth travelers,
?
So, I finally found an original expression pedal for my CS-80 after many years of searching...and it doesn't work. I understand there's a 24v5w bulb in there and thought perhaps it has burned out, anyone here have any experience opening these pedals up and
replacing the bulb?
Any hints and help greatly appreciated!
Mathias
|
Replacing bulb on Yamaha CS-80 expression pedal?
Greetings fellow synth travelers,
?
So, I finally found an original expression pedal for my CS-80 after many years of searching...and it doesn't work. I understand there's a 24v5w bulb in there and thought perhaps it has burned out, anyone here have any experience opening these pedals up and replacing the bulb?
Any hints and help greatly appreciated!
Mathias
|
Re: M Board problem - heat related.
BINGO!?
Changed the VCOs socket and all is fine.
Thanks Tommy, thanks everyone for your quick responses.
Happy end.
|
Re: M Board problem - heat related.
Hi. Yes, the problem? The IC VCO Socket !! many years ago, with the same problem I resolve only changing the Socket. ?
Il ven 8 lug 2022, 10:19 pyjamagroove via <pyjamagroove= [email protected]> ha scritto: Hi guys,
So one of my M Boards (°4 on CH I) goes silent after a warm up. I have established that the tuning goes down to the point that it's not auditable. The problems that it is almost Impossible to trace because when I take it out for inspection it cools down and sounds ok again (in tune! ).
Here is what I did so far:
1. Cleaned VCO's legs and applied fresh heat conducting agent between the IC and the diode.
2. I have bought that I have the same issue as MFox (described here ?so I have changed the IC3. Dod not work.
As I sad the problem is diagnostics. Did anyone have a similar problem?
|
Re: M Board problem - heat related.
What I would try is using a hot air station with adjustable temperature and see if I could locate the faulty component that way. ?
toggle quoted message
Show quoted text
On Jul 8, 2022, at 4:25 AM, pyjamagroove via groups.io <pyjamagroove@...> wrote:
? [Edited Message Follows]
Hi guys, So one of my M Boards (°4 on CH I) goes silent after a warm up. I have established that the tuning goes down to the point that it's not auditable. The problems that it is almost Impossible to trace because when I take it out for inspection it cools down and sounds ok again (in tune! ). Here is what I did so far: 1. Cleaned VCO's legs and applied fresh heat conducting agent between the IC and the diode. 2. I have bought that I have the same issue as MFox (described here ?so I have changed the IC3. Did not work... As I sad the problem is diagnostics. Did anyone have a similar problem?
|
Re: M Board problem - heat related.
Thanks Florian for your response.
I have to admit that you method is pretty hardcore! Personally I am afraid to do that - I might fry something in the process and there is way to many "points of interest" to check...maybe I will put the card it a sock or something..
What bothers me is that I can't find any topic on the subject (radically heat affected tuning). I suspect the transposition circuit (a FET or transistor going bad).
|
Mathias Tjonn
pyjamagroove