9pdt switch implementation

[MrStab]

what's the maximum PCB space you can allow? if there absolutely has to be 9 poles, and space and price are a concern, then i can see no other solution but SMD analogue switch IC's. what you're doing already but smaller. switching to 1/8W resistors could help if you'd rather keep a DIP package.

how often do you expect you or the user to require this feature? is it worth it, or would it be in one mode 90% of the time?

[reddesert]

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal. You can't just connect the 3 ones. Just make a schematic on your own and you can see the results. In my case there aren't grounded connections or something common for me to reduce the number of connections.

The point about 6 connections is not clear to me and a schematic of what you are trying to do would really help.

Here is a schematic I drew of to wire a single TRS jack for an expression pedal, so that it replaces either Pot 1 or Pot 2 in a circuit, using a 6PDT switch.

[just0m3]

Dear reddesert there are 3 permanent connections and 3 temporal ones on a stereo jack. According to your schematic if you haven't plugged in the expression one of two is on the air. I have made an explanation. You can see what i mean.



https://www.dropbox.com/s/3uufz1nbpuxb4ye/2017-03-24%2010.35.08.jpg?dl=0
https://www.dropbox.com/s/7adnov3s4i2n4qi/2017-03-24%2010.34.37.jpg?dl=0

[potul]

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal. You can't just connect the 3 ones. Just make a schematic on your own and you can see the results. In my case there aren't grounded connections or something common for me to reduce the number of connections.

The point about 6 connections is not clear to me and a schematic of what you are trying to do would really help.

Here is a schematic I drew of to wire a single TRS jack for an expression pedal, so that it replaces either Pot 1 or Pot 2 in a circuit, using a 6PDT switch.

You can achieve the same with one less switch. You can leave one of the pots leg connected to the circuit if the other 2 are NC. This fees up one switch.
So a 5PDT can be used.
If there is any common point in the pedal schematic, you could remove as well other switches (ie: if both pots are connected to ground)

[potul]

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal. You can't just connect the 3 ones. Just make a schematic on your own and you can see the results. In my case there aren't grounded connections or something common for me to reduce the number of connections.

The point about 6 connections is not clear to me and a schematic of what you are trying to do would really help.

Here is a schematic I drew of to wire a single TRS jack for an expression pedal, so that it replaces either Pot 1 or Pot 2 in a circuit, using a 6PDT switch.

You can achieve the same with one less switch. You can leave one of the pots leg connected to the circuit if the other 2 are NC. This fees up one switch.
So a 5PDT can be used.
If there is any common point in the pedal schematic, you could remove as well other switches (ie: if both pots are connected to ground)

In fact, depending on the pedal, you can even leave the 2 external lugs connected and just disconnect the wiper without noticeable issues. I've done this in the past in some pedals.
If you tell us the schematic of the pedal you plan to control it would help.

[just0m3]

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal. You can't just connect the 3 ones. Just make a schematic on your own and you can see the results. In my case there aren't grounded connections or something common for me to reduce the number of connections.

The point about 6 connections is not clear to me and a schematic of what you are trying to do would really help.

Here is a schematic I drew of to wire a single TRS jack for an expression pedal, so that it replaces either Pot 1 or Pot 2 in a circuit, using a 6PDT switch.

You can achieve the same with one less switch. You can leave one of the pots leg connected to the circuit if the other 2 are NC. This fees up one switch.
So a 5PDT can be used.
If there is any common point in the pedal schematic, you could remove as well other switches (ie: if both pots are connected to ground)

In fact, depending on the pedal, you can even leave the 2 external lugs connected and just disconnect the wiper without noticeable issues. I've done this in the past in some pedals.
If you tell us the schematic of the pedal you plan to control it would help.

Notice my last post upwards and re-think about it

[anotherjim]

Which of these cases are in the objective?

Case 1: Pedal in use replacing pot A.
Case 2: Pedal in use replacing pot B.
Case 3: Pedal plugged in, but neither pot affected.
Case 4: No Pedal, no pots affected.

If Case 3 is required, don't you need 3way switching?
Case 4 needs to employ some jack socket switching.

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal.

These extra 3 jack contacts are known to me as "normalising" contacts. Often found used in patch bays to provide a normal "hardwired" path between equipment while no plug is fitted, but that path is broken and diverted when a cable is plugged in. They can have other uses.

In case 4, the absent expression pedal means a path should be established back to the panel pot that is currently selected for the expression?

[just0m3]

Which of these cases are in the objective?

Case 1: Pedal in use replacing pot A.
Case 2: Pedal in use replacing pot B.
Case 3: Pedal plugged in, but neither pot affected.
Case 4: No Pedal, no pots affected.

If Case 3 is required, don't you need 3way switching?
Case 4 needs to employ some jack socket switching.

The thing is that a stereo expression jack has 6 connections. 3 are permanent connected and 3 are temporal.

These extra 3 jack contacts are known to me as "normalising" contacts. Often found used in patch bays to provide a normal "hardwired" path between equipment while no plug is fitted, but that path is broken and diverted when a cable is plugged in. They can have other uses.

In case 4, the absent expression pedal means a path should be established back to the panel pot that is currently selected for the expression?

The case is this :
You have to pots in your circuit controlling different parameters. You want to use one expression jack and swap from one to another with a single switch. If you haven't connected an expression pedal in your jack neither pot is affected and the circuit uses the 2 pots. If you connect an expression one pot goes away and is replaced by the expression pedal. With you switch you can swap the pots ( that affects the remaining circuit ).

[anotherjim]

That would be cases 1, 2 & 4 then?

[potul]

The case is this :
You have to pots in your circuit controlling different parameters. You want to use one expression jack and swap from one to another with a single switch. If you haven't connected an expression pedal in your jack neither pot is affected and the circuit uses the 2 pots. If you connect an expression one pot goes away and is replaced by the expression pedal. With you switch you can swap the pots ( that affects the remaining circuit ).

Ok, this should have been the first step... explain what you need. The other piece we need in order to give good advice is to know the circuit you try to apply it to. Or do you want a generic solution that works for all?

[just0m3]

The case is this :
You have to pots in your circuit controlling different parameters. You want to use one expression jack and swap from one to another with a single switch. If you haven't connected an expression pedal in your jack neither pot is affected and the circuit uses the 2 pots. If you connect an expression one pot goes away and is replaced by the expression pedal. With you switch you can swap the pots ( that affects the remaining circuit ).

Ok, this should have been the first step... explain what you need. The other piece we need in order to give good advice is to know the circuit you try to apply it to. Or do you want a generic solution that works for all?

A genetic is needed. Further implementations additions and improvements will be designed according to the demands of the case

[potul]

The requirement of the "normalized" jack  really complicates things.... I don't even see how a 9pdt would do it. Usually these work so that when you insert a jack, you break the connection of  the pot to the circuit. In your case you would need to break only the one that is selected by the switch... I don't get an easy way tot achieve this

[reddesert]

Yes, it is really necessary to specify all the details of the application when you're trying to get help building something.

It would be possible to use the 3 NC contacts (closed when the jack is removed) to wire one pot, either Pot 1 or Pot 2 to the jack contacts. This would allow the 6pdt circuit above to work when the pedal is in use, and when the pedal is removed, to work in one setting of the double-throw switch, but not the other.

To have both pots sense when the jack is removed, you might need another 6pdt switch that is switched by a trigger on one of the NC contacts. At that point it's overly complex IMO.