Switch with optocoupler and clean channel jcm800

[giordydiver]

Hi guys i added clean channel to my jcm800 bypassing v1b and using rele for gain and master but because bob problem i decided to make this mod using optocoupler.
For this mod i use like referring soldano slo schematic which use optocoupler vtl5c1 to switch master and channel. I think also to change way for clean channel. I thind to make in this way:
OD channel v1a --treble peak--gain pot(1M audio) --v1b
Clean channal v1a--treble peak/voltage divider--gain pot(500k audio)--v1b

My mind is this, the clean tone of od channel( gain about 2 3 ) is more beautiful than clean with v1b bypassed, so i think to use the same configuration but for clean channel use a voltage divider(470k/470k) and gain pot of 500k, in this way i should reduce gain about 50% and have a good clean channel. For switch clean od channel I thing to do like master volume of soldano slo, while for master volume and power suppy i will use the same of soldano slo.

What to you thing about this way for clean channel? Are in this way the two channel completly indipendent?

This is schematich of my idea and the schematic of soldano slo
http://www.slocloneforums.com/download/file.php?id=1339

[Haze13]

It can work, but if a I wanted to have a clean on the JCM800, I would use another tube for it, because I prefer others settings of the tone stack on cleans... For now I just use a neck pick-up

[giordydiver]

Yes, i not the fender clean but for me the principal tone il overdrive, clean is only for have more tonal range. Also byoassing v1b i have not a real clean channel, but i like more the clean of od channel with low gain setting, for this this choise...only one thins, in this way channel are 100% indipendend? I have this question because output pot are separated but signal is in both pot, i dont want that one channal is influenced by other gain pot

[giordydiver]

For power optoisolar i decided to not use voltage from heater( it can be add noise) but use a little transformers with 3va 6v 500ma,is this ok? must i change something than original schematic where trasformers has 6.3v 2A?
http://postimg.org/image/9lweo8w6f/full/

[Haze13]

with a 3 watt transformer you can build a 1 watt amp!
Don't see any problem with it, just make sure that it will not interfere with other transformers... There is a reason why they are 90 degrees to each other, right? The magnetic field
The whole scheme will take less current than a 6.3v pilot light I think... Why use another transformer?

[giordydiver]

with a 3 watt transformer you can build a 1 watt amp!
Don't see any problem with it, just make sure that it will not interfere with other transformers... There is a reason why they are 90 degrees to each other, right? The magnetic field
The whole scheme will take less current than a 6.3v pilot light I think... Why use another transformer?

yes I know, but is a little transformer I dont think that it can interfere with other transformer, however it will be mounted away from other trasformers and away from valve. this optoisolator work at 3v but 6v transformer is more available that 3v for me. I have the schematic with 6.3v power supply, i use the same with 6v transformer , if voltage are the same that is good, if not I change resistors after bridge rectifier to have the right voltages.
This is schematic and layout for ldr power supply, i add a ldr befor clean treble peak to bypass completly clean tone when overdrive is on. Another change is voltage divider, use 39k to ground to have a lot of gain loss

about preamp, two channel work indipendently or they are bleed in this way? Same question for two master....is my only doubt

[img=http://s15.postimg.org/99d1qsa87/image.jpg]

[giordydiver]

nothing?

[Haze13]

Independent? You mean one work and other is not? I think yes. Optocouplers have small resistance or very large - so you can think of them like short circuit or open circuit.

[giordydiver]

I mean that one pot dont influence other pot . I ask if they work 100% indipendently so clean section dont influence overdrive channel, and if od section dont influence clean channel.

[Haze13]

Yes, they are independent.

[giordydiver]

Ok thanks.
Last thmg , transformator for ldr will be installed on the other side of IEC power jack, so i must bring two wire from iec to ldr transformer passing them under turret board".it could be a problem? Explecially for hum...

[Haze13]

Just twist them and I think there shouldn't be any problems. But once again - you can do without it... Don't forget to use a fuse before it The right one of course.

[giordydiver]

Just twist them and I think there shouldn't be any problems. But once again - you can do without it... Don't forget to use a fuse before it The right one of course.

the fuse beetwen 230v and transformers right? 230v 0.4a is good? transformer has 230v 6v 480ma

[Haze13]

You set the value of the fuse according to a max power of the secondary winding. P=V*I. So 3 watts is less than 230V*0.4A. Fuse has to be smaller.

[giordydiver]

Ok, so in this way I is 15ma but i know that when turn on could be an highter voltage for an instant... Put 30ma ?