Reverse relay state for footswitch LEDS? SOLVED!

[rogb]

Hi all,
I've recently dug out my 2017 #183 1U preamp.
It's working perfectly so I decided to build an OD/PAB footswitch. No problem I've built around 4. The rear manual switches work fine too.
Problem is although the switching works perfectly I cannot get the LEDS on when OD or PAB is engaged. It works fine the opposite way which leads me to think the ON state is when the coil is de-energised.
I have tried both 5v and 12v from the regulators in this preamp prototype but it makes no difference. Nor does changing LED resistor values.

Right now I've tried 12v to the LEDS and the 5v relay supply going to pin 4. Also the Brown Note style that always worked before.
I have tried everything I can find but without luck. It's been so long I can't find my original relay diagram that Martin Manning (or Structo) supplied.
Thanks and I hope you are all fine. Think this is my 13th year on TAG. Wow!

[martin manning]

Hi Rog, got any schematics of what you are trying to do?

[Stephen1966]

Hi all,
I've recently dug out my 2017 #183 1U preamp.
It's working perfectly so I decided to build an OD/PAB footswitch. No problem I've built around 4. The rear manual switches work fine too.
Problem is although the switching works perfectly I cannot get the LEDS on when OD or PAB is engaged. It works fine the opposite way which leads me to think the ON state is when the coil is de-energised.
I have tried both 5v and 12v from the regulators in this preamp prototype but it makes no difference. Nor does changing LED resistor values.

Right now I've tried 12v to the LEDS and the 5v relay supply going to pin 4. Also the Brown Note style that always worked before.
I have tried everything I can find but without luck. It's been so long I can't find my original relay diagram that Martin Manning (or Structo) supplied.
Thanks and I hope you are all fine. Think this is my 13th year on TAG. Wow!

ON state is when the coil is de-energised.../works fine the other way - recommend you double check your LED polarity with respect to the flyback diode on the coil.

[rogb]

Hi Rog, got any schematics of what you are trying to do?

I haven't got any paperwork for this. I guess I've moved 6 times since then. I just took 183 preamp and added the needed circuits for 230 and 12v from flatpack transformers.

[rogb]

Hi all,
I've recently dug out my 2017 #183 1U preamp.
It's working perfectly so I decided to build an OD/PAB footswitch. No problem I've built around 4. The rear manual switches work fine too.
Problem is although the switching works perfectly I cannot get the LEDS on when OD or PAB is engaged. It works fine the opposite way which leads me to think the ON state is when the coil is de-energised.
I have tried both 5v and 12v from the regulators in this preamp prototype but it makes no difference. Nor does changing LED resistor values.

Right now I've tried 12v to the LEDS and the 5v relay supply going to pin 4. Also the Brown Note style that always worked before.
I have tried everything I can find but without luck. It's been so long I can't find my original relay diagram that Martin Manning (or Structo) supplied.
Thanks and I hope you are all fine. Think this is my 13th year on TAG. Wow!

ON state is when the coil is de-energised.../works fine the other way - recommend you double check your LED polarity with respect to the flyback diode on the coil.

Yes the ON state is when the coil is de-energised. Any reason the ON state can't be reversed. Didn't some use OD as the default coil state ISTR,

[rogb]

The build thread
https://ampgarage.com/forum/viewtopic.php?f=4&t=30038

[rogb]

Pretty certain I wired up according to this

Taylor_OD_Relay_R1.jpg

[martin manning]

Hi Rog, got any schematics of what you are trying to do?

I haven't got any paperwork for this. I guess I've moved 6 times since then. I just took 183 preamp and added the needed circuits for 230 and 12v from flatpack transformers.

So it was all manual, rear switches only, and now you want to add a foot switch. Do you have relays installed now?

[rogb]

Hi Rog, got any schematics of what you are trying to do?

I haven't got any paperwork for this. I guess I've moved 6 times since then. I just took 183 preamp and added the needed circuits for 230 and 12v from flatpack transformers.

So it was all manual, rear switches only, and now you want to add a foot switch. Do you have relays installed now?

It's always had relays and rear switching. It used to work on my old footswitch but I can't remember if the LEDS did... nearly 6 years since I did this lol. The footswitch and that 100w rig are long gone now.
Yes Martin the footswitch works perfectly on OD and PAB. Just the LEDS only come on when OD/PAB are off.

[martin manning]

Yes Martin the footswitch works perfectly on OD and PAB. Just the LEDS only come on when OD/PAB are off.

ok, so do you have the separate 12V power lead going to the foot switch or are you using the relay coil current to turn he LED's on?

[rogb]

Yes Martin the footswitch works perfectly on OD and PAB. Just the LEDS only come on when OD/PAB are off.

ok, so do you have the separate 12V power lead going to the foot switch or are you using the relay coil current to turn he LED's on?

I've tried all ways. But not with the 2 x 5v from the 1K resistors on the PS. Maybe I need to run the 2 separate 5v supplies to pins 1 and 5? As per the layout

[Stephen1966]

Pretty sure this would work for you. If they are non-latching relays the flyback diode on the coil orientation could go either way.

The LED B+ is part of the line that feeds the coils, switching a relay off breaks the continuity to ground. Seems your LEDs are providing a path to ground with the relay off. Curious!

This design works though...

LEDs + Relays.jpg

Edit: Just noticed I've got my relay ports mislabelled for the chassis switches on the schematic. Ports out on the relays are correct though and the switches themselves are labelled correctly. I corrected this and replaced it with a correct schematic.

[martin manning]

Yes Martin the footswitch works perfectly on OD and PAB. Just the LEDS only come on when OD/PAB are off.

ok, so do you have the separate 12V power lead going to the foot switch or are you using the relay coil current to turn he LED's on?

I've tried all ways. But not with the 2 x 5v from the 1K resistors on the PS. Maybe I need to run the 2 separate 5v supplies to pins 1 and 5? As per the layout

There are a number of ways to make it work. See here https://ampgarage.com/forum/viewtopic.p ... 006#p55006 for the original D ODS style, where a supply lead for each function runs to the XLR/DIN jack, with the current limiting resistors on the chassis side. That means 5 pins are needed for two functions. I prefer to run a single 12V or 5V supply lead through the jack, and put the current limiting resistors in the foot switch, Then 5 pins can support three functions.

[rogb]

ok, so do you have the separate 12V power lead going to the foot switch or are you using the relay coil current to turn he LED's on?

I've tried all ways. But not with the 2 x 5v from the 1K resistors on the PS. Maybe I need to run the 2 separate 5v supplies to pins 1 and 5? As per the layout

There are a number of ways to make it work. See here https://ampgarage.com/forum/viewtopic.p ... 006#p55006 for the original D ODS style, where a supply lead for each function runs to the XLR/DIN jack, with the current limiting resistors on the chassis side. That means 5 pins are needed for two functions. I prefer to run a single 12V or 5V supply lead through the jack, and put the current limiting resistors in the foot switch, Then 5 pins can support three functions.

Thanks Martin I have always made my footswitch this way. The annoying thing is that the switches work fine without the LEDS and with LEDS on 5 or 12v, also work, but somehow the LEDS are getting powered in the OFF state rather than ON. I have tried every way I can find so far.

FOOTSWITCH_3.jpg

[rogb]

Pretty sure this would work for you. If they are non-latching relays the flyback diode on the coil orientation could go either way.

The LED B+ is part of the line that feeds the coils, switching a relay off breaks the continuity to ground. Seems your LEDs are providing a path to ground with the relay off. Curious!

This design works though...


LEDs + Relays.jpg


Edit: Just noticed I've got my relay ports mislabelled for the chassis switches on the schematic. Ports out on the relays are correct though and the switches themselves are labelled correctly. I corrected this and replaced it with a correct schematic.

Thanks Stephen that looks helpful. I'll study the schematic and see how much rewiring is needed.