Projector Remote Control Wiring

[StradivariusBone]

Trying to wire our projector's remote control to the sound booth. Projector has RS-232 and we've got a controller panel on the wall, but it only turns it on and off and it's not in the booth. In the past I've seen setups that used audio cable (as it is a 1/8" TRS) so I patched it through our building wiring. All is well to a point. Our sound booth is an addition and so I patched to the nearest mic input and then ran a new mic cable for the "last mile".

The remote will work at the input (post-patchbay), but fails when I run it over my extension. I'm guessing there's a signal limitation since there's a few terminations in line (projector->TRS-XLR adapter->mic cable->wall plate->patchbay->wallplate->extension->XLR-TRS adapter->remote). I've got enough Cat5 to run it straight, but didn't want to waste it without reasonable evidence to believe it would make a difference. I'm assuming it's some type of serial data and probably RS-232 as well, so it theoretically should be happier on twisted pair as opposed to mic cable. Google-fu is failing me, I can't even find a pinout.

 

[MNicolai]

Mic cable is perfectly acceptable for this application.

First thing I would do is move your adapters out to the projector and try your signal chain at the projector, without going through the patchbay. You want to verify your adapters are giving you a direct 1:1 pass through on your pin-out and that your projector still responds to the remote with the adapters in-line.

I would also double check the pin-out on the new cable you ran. Check both ends.

Shell - Not connected
Pin 1 - Ground
Pin 2 - Positive (Red/White)
Pin 3 - Negative (Black)

Then I would look at or take photos of your patchbay wiring. My guess is that your patchbay is not doing a 1:1 pass through. Maybe your grounds are lifted/bussed and that is causing the disruption.

 

[StradivariusBone]

I had done all that. It works fine all the way through the patchbay to the other port, but when I plug in the extension to the booth it won't work. I have tested the extension and verified it's all 1-1 and terminated correctly. Prior to putting new batteries in the remote it didn't even work connected with just the adapters at the projector. So based on troubleshooting alone, I'm pretty confident this is a signal dropout problem as opposed to cable issues, I just can't find any documentation that would reassure me that the distance I'm shooting for is even possible, regardless of the cable medium. If I had to guess it's in the ballpark of a 120-150' run. Most serial data should be able to do that, but with mic cable and multiple terminations the likelihood of signal degradation increases.

 

[MNicolai]

Just looked up the manual for a Panasonic projector and they have a hard limitation on 49'3" for using the remote connection. Not sure if that applies to your projector, and and it's hard to know what that actually means though if that's based on some spec or if that's tested and found to be a reliably firm failure point.

If you have some dry links between your stage and booth intended for DMX, you could try hijacking those instead. The lower capacitance cable may preserve the digital waveform over a longer distance.

Otherwise you can look at doing something like a Xantech IR extender out to your projector over CAT6, or depending on your control system and use of the room, relocate the existing control panel or add a control panel.

 

[StradivariusBone]

It's crazy how little info there is about this setup. I guess everyone just networks their projectors and deals with it over a web interface. This one is an Epson and the manual mentions it briefly but goes into no detail. Thanks for the insight, that's a good idea to try first with a DMX cable. I've got enough of those around to at least do a proof of concept.

 

[RonHebbard]

Trying to wire our projector's remote control to the sound booth. Projector has RS-232 and we've got a controller panel on the wall, but it only turns it on and off and it's not in the booth. In the past I've seen setups that used audio cable (as it is a 1/8" TRS) so I patched it through our building wiring. All is well to a point. Our sound booth is an addition and so I patched to the nearest mic input and then ran a new mic cable for the "last mile".

The remote will work at the input (post-patchbay), but fails when I run it over my extension. I'm guessing there's a signal limitation since there's a few terminations in line (projector->TRS-XLR adapter->mic cable->wall plate->patchbay->wallplate->extension->XLR-TRS adapter->remote). I've got enough Cat5 to run it straight, but didn't want to waste it without reasonable evidence to believe it would make a difference. I'm assuming it's some type of serial data and probably RS-232 as well, so it theoretically should be happier on twisted pair as opposed to mic cable. Google-fu is failing me, I can't even find a pinout.

@StradivariusBone Let me bore you with a concept and leave you to finesse the details on your own.
Without getting into the minutia of pin-outs and various connector types, I'll address your stated concern of: "I've got enough Cat5 to run it straight, but didn't want to waste it without reasonable evidence to believe it would make a difference."
Consider the following as a starting point:
Get your projector, its remote and your Cat5 all conveniently in front of you.
Connect remote to projector, power and test all functions.
If all is well so far, disconnect the remote from the projector and temporarily insert your stock of Cat5, all of it, whatever your uncut length on hand happens to be. Basically, strip the ends and paste it together.
It's ether going to work or not.
If it works, install your Cat5, cut off the excess and proceed with optimism.
If it doesn't work, shorten your Cat5 to a length known to be slightly longer than what will be required for your installation, cut your stock, strip the end and retest. If it works, proceed with your installation. If it doesn't work, you've still got all of your Cat5, still in good condition although in two pieces. You've saved the time of installing and removing and you know you've still got your problems to solve.
Perhaps this sounds a little simplistic, obvious and pointless but it's a technique that's served me well when bending equipment manufacturer's rules and guidelines regarding recommended maximum lengths for various interconnection cables.
One boring example:
Maximum cable lengths between AC servo drive controllers and their associated motors.
Manufacturer, used to their products being employed on automated assembly lines and / or automated precision machine tools; Lathes, vertical and horizontal mills for example, specifies: "Resolver cables may be 15' to 25' long. Contact the factory for any applications longer than 25'."
Us: "Hello. Our application will require bridge, resolver, and electro-mechanical brake cables 150' long."
Them: [Cough, gag.] "No phuquing way!"
Us: "Thank you very much, have a good day."
Next steps:
As we were purchasing raw cables on 500' and / or 1,000' reels and 'UnReel' cartons, we extracted both ends of full length put-ups, stripped the ends and lashed together a test rig.
Directors and technicians strive for accuracy and repeatability in their theatrical automation applications but there's a big difference between worrying about one or two thousandths of an inch when positioning and re-positioning your lathe's tool post compared to parking a dancing pin-ball machine on its spike-marks 8 shows a week.
In our case: 1,000' foot cables. Pretty darned impressive. 500' cables phuquing marvellous!
Pre-cut cables to 150', solder / crimp connectors. Test in shop. Ship to Offenbach / Frankfurt, Germany. Await arrival of shipping containers. Sleep nights sans worries. Fly to Germany, install, program, stick around through previews, enjoy opening night festivities, fly home.
One year later; 1996 not that the year matters.
Producers: "Can we do this all again for London, England?"
Us: Fly to England. Scout out venue. Realize we'll need 200' cables this time.
Manufacturer: "Contact the factory for any applications longer than 25'."
Us: "Phuque that noise!"
Install connectors on free ends of 500' and 1,000' put ups.
Chop at 400' and install opposite ends.
Set up test rigs.
Be amazed by how well everything works.
Cut 400' cables in half at 200'.
Install remaining connectors.
Test, label, pack, ship to England, sleep well waiting for the boats.
Fly to London, install, program, stick around through previews, enjoy opening night festivities, fly home.
Bottom line: Never be afraid to think outside the box, and bend 'their' guidelines, whomever "their" may be.
Keep in mind common sense priorities such as ALWAYS having health, safety, and potential for destructive damage foremost in mind and, to paraphrase one of our respected regular posters: 'Always remember you're responsible for your own safety and activities.'
Optimistically there's a nugget or two in here for you @StradivariusBone
Toodleoo!
Ron Hebbard

 

[mikefellh]

It's crazy how little info there is about this setup. I guess everyone just networks their projectors and deals with it over a web interface.

I agree as I've had the same issue with finding info about signal extenders because it's not a common thing most people use.

I've actually found that the IR projector remotes provided with projectors are extra bright and powerful enough (good for 40feet away), and I bought extra IR remotes and velcroed one to the lectern (so it never gets lost) and pointed towards the projection booth (and it works with the houselights on).

 

[FMEng]

Cat 5 isn't a good idea for RS-232. You need shielded cable. My guess is you have a ground loop somewhere from going through patch panels. Try a continuous piece of Belden 9451 or 8451. If that doesn't do it, B&B Electronics has isolated, RS-422 converters that can extend serial over great distances. RS-422 is the balanced form of RS-232. Balancing gives it noise immunity that RS-232 does not have.

 

[StradivariusBone]

Well, yeah, but I've got a bunch of Cat 5 and when your only tool is a hammer...

I did bite the bullet and put in a run from the projector to the booth. I figured that the worst of it all is I'd end up being able to network the projector and go the web route. But it worked! I was curious so I tested to see whether it needed tip ring and sleeve or just two conductors and it worked on two, so I think that confirms 232 as opposed to any sort of balanced signal.

In any event, it works. It's not show-critical, just show-convenient so I'm OK with it maybe dropping a bit here and there. At least future Googlers will have something to go on.