Cu1 vent

[beaufighter]

I want a traditional selector for my Neo Vent so looking at the CU1. Anyone out there know please whether this would be compatible and what is the length of the jack lead? Thanks

[jbird604]

I just ordered in a new Vent for a customer but haven't installed it yet. I looked at the owner's guide that came with it, and it explains how to set the unit to work with a variety of switches, such as the CU-1 (specifically mentions it). I assume it works with any simple on/off switch you wire it to. A 3-position switch is needed if you want the "stop" function enabled.

[beaufighter]

Thanks John. Good when something is straightforward.

[Drawbar Dave]

You can make your own with an existing three position half moon, just adding a stereo jack to the end. If I remember correctly, the Vent schematic is wrong for switching. On that Vent pdf I posted on your other thread it explains the correction.

[jbird604]

Yes, I discovered today that it DOES require a double-throw switch. I finally got around to installing it on the organ, and found that, regardless of how I tinkered with the switch modes and such, you MUST insert a 3-circuit plug into the jack (a stereo 1/4" phone plug, as used for old-fashioned stereo headphones). Then you must wire your switch so that you can ground either the tip or the ring individually. Grounding the tip turns on one of the motors, and grounding the ring turns on the other motor. Apparently that is just the way it works, so it won't work with a simple single-throw switch like we use for the basic 122 cabinet.

Of course that's no problem. The CU-1 is a double-throw switch already, and of course the half-moon comes in that configuration too, if you order it that way. Just be sure to use it that way. Use the shield ("sleeve") terminal on the stereo phone jack as ground or common on your switch, and connect the other two to the two normally open terminals. Whichever one is shorted to the ground at a given time controls the speed. If neither one is grounded, the rotor will stop, though not instantly. To force a "brake" you have to short the tip and ring together. I don't know if the CU-1 does this or not.

It is also possible to set the Vent to respond to momentary contact switches, but that seems pretty useless on an organ unless you want to put a kick-switch on your expression pedal.

[beaufighter]

Dave, John Thank you for posts. Looks as though a little tinkering and adaptation to an old half moon switch I have could do the job. I was saving this for my T500 and Leslie 145 project but that's a way off anyhow as time has too many demands! I'm cautious of putting a wire where it will cause damage to some fine circuitry. Way back when it was all analogue all appeared to be more forgiving should a connection not be as it should. Would you expect there to be damage to vent or xe200 should connections be wrongly made. I'm guessing that there is a need to ground certain signals via the switch but in doing so, should the ground be made where it shouldn't will this cause damage or simply not work. Thanks Sean

[jbird604]

I guess if it were easy to damage the Vent's remote jack I would've done it, as I first plugged in a standard mono 1/4" plug, effectively shorting the ring and sleeve. I was trying to switch speeds by simply connecting and disconnecting tip to ground, which of course didn't do anything at all, since the ring and sleeve being permanently shorted by the mono plug was overriding anything else I tried to do.

But no harm done. Once I inserted a stereo plug and started experimenting it worked exactly as it's supposed to.

Obviously when you hook it up you want to keep your wires safe. I suppose it would damage the Vent if one of them came into contact with a voltage-carrying metal part. Easiest and safest approach is probably to use a shielded audio cable with two signal wires, such as XLR microphone cable. Connect the shield to the sleeve terminal and one signal wire each to the tip and ring. At the other end, connect the shield to the switch common and one signal wire each to the "fast" and "slow" terminals of the switch.

[beaufighter]

That makes sense John and reassuring. I have a few lengths of this cable so will set to work. Should be able to fabricate a half moon switch too. Thanks Sean