That's just plain weird.

I have a 120VAC power source and I have a device that works on 120VAC. But it won't work because there's no battery. That's what this sounds like.

12 volt trigger inputs take 12VDC (some have wider voltage ranges, some also take AC). "CEC is a feature of the HDMI standard," per the lovely Brit at . This has nothing to do with the comparatively stupid (but effective) 12 volt trigger. "Because it's not CEC" is not a valid reason.

I don't want to complain about the tech I spoke to but they could not tell me what the 12v trigger did (assuming it did not turn unit on). They gave me a case number and told me since the unit was about 9 years old that they would have to go into archives.

Maybe I should check the processors batteries. But seriously thanks for your help. Thought it would be just a simple thing. I may check the jacks with a voltmeter just to see if 12 v are present but that's as far as I can take this. There did not seem to be a setting on the Arcam that switched the trigger on or off. There is such a setting on the HQV and I have both triggers "on". The 3.5mm is stereo and that's what the Arcam calls for. If any other thoughts I would be happy to hear but otherwise I will call it a day.

It might help to think of the jacks not as stereo, but as three terminals. Yes, it's the same plug and jack, but thinking of it in terms of how it's used might help make sense of some things.

For instance, the sleeve would probably be ground, the tip likely the hot, and the ring -- what could that be for?

The same mini plugs were used in the first Pronto type and URC remotes and such, which used RS232 with the sleeve as ground, tip as send, and ring as receive. (Prontos did it one way, tip and ring were the reverse in URC product.)

Definitely check the batteries on the processors. I'm surprised they have any, and more surprised that you didn't check them already. Anything that WILL FAIL after time should be checked first!

From the Arcam Manual (but for zone 2)


The 3.5mm jack plug for this connector is wired
as follows:
3.5mm stereo jack Function
Tip Signal
Ring 0V
Sleeve 12V,
30mA current-limited

But what I am reading into is that perhaps the Epson and Arcam use different sites for signal ring ground (perhaps reversed)

Putting the positive voltage on the sleeve is pretty rare, mostly because we always tend to think of these connectors as.... stereo connectors, not just three terminals. But that actually makes the most sense: the last thing connected is the 12 volts, and if either the tip or ring were 12 volts, it would connect to other terminals of the jack during plug-in.

A thing to be concerned about is the current limiting. I once had to build a small DC amplifier (basically just a 2N3904, IIRC) to get enough current for the trigger or a Marantz projector to drop a Chief projector lift out of the ceiling.

Okay, Ring is 0 volts, but is it connected to ground? Is it open? Does it go hot when a trigger happens?

will check and get back



I measured the voltage readings from the HQV processor port and see 12 v
Does this speak against it being a trigger in?

Yes. An "input" usually waits for a voltage and will measure at or near zero while waiting.

If you measure zero, the reading is ambiguous because this could be an input waiting for a signal or an output that is not currently asserted.

Keep monitoring this voltage and make note of if and when this voltage changes.

---

I'm not familiar with this projector. Many projectors have an option for an auto shut down if there is no signal for some minutes. This would be somewhat annoying as a control strategy because the projector will obviously be active for a while after the operator gives the Power Off command through the control system, but at least the projector will eventually shut down.

The thing about measuring zero volts is that the place you're measuring could be an input; could be an output at zero state; could be disconnected entirely from everything.

So once you see it's zero volts, turn everything off and measure its resistance to ground. Reverse the polarity of the ohmmeter leads and measure it again.

Zero ohms means it's grounded. Infinite ohms means it's open. A resistance measurement that changes when you reverse the polarity means it's connected to some semiconductor circuit, whether output or input.

Zero ohms that rapidly increases to some high value means the major item connected to that thing is a capacitor.

How much do you understand about input and output circuitry?

This depends on the measurement voltage used by the meter. I had a little pen style meter that used such a low voltage for resistance measurements that semiconductors would not turn ON. It's easy enough to check your meter for this characteristic -- simply measure the resistance of a diode, then reverse the leads and measure again. If the readings are dramatically different, your meter can turn ON a semiconductor.

Read above
My understanding of input and output relative to you (Ernie) would be "not very much"
But if I am getting a 12 V reading from the processor (not avr) when its on and 0 when its off does that give me any indication at all if this was trigger in or out.
The Epson tech team literally told me no further documentation is available.

This is an output and could be used, for example, to drop a screen if a constant +12VDC means "drop" when sent to the screen controller and changing to 0V will imply "raise".

A fine point would be checking the current available from the output and the current required by the controlled item.

For example, if the output port can source 20mA, but the controlled item requires 100mA, this output port cannot control the item.

To clarify: This voltage (12V) tip to shield , indicates the processor port is an "output"
If so it will not serve my purpose which was simply "to trigger on the video hqv processor" from my AVR.

Again.....Epson told me this was an "in" not out but I think they are wrong.

Going back to your Post 10 and Fred's Post 4, is seems that your goal is simply to shut down the processor.

Before you invest any more time in this project, simply pull the power cord from the processor when you want it to shut down. Then restore power when you want the processor to restart. Does the system still behave normally? Potential issues could be that the processor will not restart after simply restoring power or that the processor will drop some settings or will require an unreasonable amount of time to resume operation.

If the processor behaves well enough under these conditions, then use a trigger output and relay to control power to the processor.

Understood
Thanks
BK


Any favorite relays: kits etc?

I'm not endorsing this particular product because I just found it after a quick search. The key feature is that power drawn in one outlet will switch other outlets. This might be a very quick and straight forward solution for you. I've seen similar products in Home Depot and Lowes.

A potential issue for any such product is that some items draw a small current in "standby" and more current in "run" mode. If the product cannot discriminate  between "standby" and "run" modes, the controlled outlets will not switch.