Monitor controls - presets idea

[Minwah]

The other day I had an idea...

I have an xbox & PC in my cabinet...and also possibly a DC in the future (it has been in and out a few times!).  One small problem is that different systems often use different refresh rates, or have different size video outputs.

For example I have my screen adjusted to best display PC stuff (MAME).  When I use the xbox, the picture does not quite fill the screen vertically.  I could adjust the monitor controls every time but I can't be bothered so I just live with it.

So I was thinking about making some kind of device which could be used to switch between one 'preset' monitor setting an another.  Lets say for example I wanted to be able to switch v-size easily.  I could remove the v-size pot, and extend wires from the monitor control board to this device.  It would consist of 2 pots of the same value as the original v-size one, which can be switched between using a DPDT switch (I think).

So although the switching is still manual, flicking a switch is easier than adjusting pots.  This method could be done for any of the controls, for example v-hold would be handy if using a mixture of 60hz and 50hz consoles/systems.

Can anyone see why this wouldn't work?  Or any other comments?

[2600]

I only see 2 possible downsides, but have no idea if they are actually valid.

1. How does a monitor react when a pot is not connected? This would basically be happening when you turn the switch.

2. Having it external may cause some picture degredation?  Not sure how likely, but it is possible.

Otherwise, good idea.  Do you have an idea for how many pots you would need?


Depending on how much you wanted to work, here is another idea.  Use a digital pot and connect it to your computer.  The digital pots should be pretty easy to interface with to a computer.  Some have a memory to store a default setting while others start off at mid value.  Any time you wanted to change a setting, you would just send the command to the pot.  This is of course assuming you can find one that fits all the requirements, not sure what values we are talking about myself.

You could also do it like your PC monitor or the D9200 does.  They have several presets for different resolutions so you fiddle with it once for each resolution, but it stores it.  Not sure exactly how that is done.

[Minwah]

1. How does a monitor react when a pot is not connected? This would basically be happening when you turn the switch.

I agree it might be an issue...maybe connecting some kind of minimum value normal resistor permanently might work.  Then again, my monitor controls are detachable and when not connected I think the display justs goes off.

2. Having it external may cause some picture degredation?  Not sure how likely, but it is possible.

Maybe, but my standard monitor controls are detachable, and I have them mounted using a (official manufacturer's) long ribbon cable.  It doesn't affect performance noticably, I guess because it doesn't have much to do with the actual video signal (?).

Otherwise, good idea.  Do you have an idea for how many pots you would need?

I suppose 2 for each type of control.  I could probably currently live with just v-size, but I would add v-hold also.  Horizontal size, and the more advanced controls never seem to need adjusting.

Depending on how much you wanted to work, here is another idea.  Use a digital pot and connect it to your computer.  The digital pots should be pretty easy to interface with to a computer.  Some have a memory to store a default setting while others start off at mid value.  Any time you wanted to change a setting, you would just send the command to the pot.  This is of course assuming you can find one that fits all the requirements, not sure what values we are talking about myself.

Good idea but probably a bit complicated for what I want.  Also, if you mean the PC would control the pots then my PC is not always on (ie when I'm using xbox) so it wouldn't work.

You could also do it like your PC monitor or the D9200 does.  They have several presets for different resolutions so you fiddle with it once for each resolution, but it stores it.  Not sure exactly how that is done.

Again I think this is a bit complicated for me...I don't know how these monitors work either.

I think assuming the first issue raised isn't really a problem (some testing would find out for sure) then I could make a small project box with a couple of switches in and access to the pots for adjusting.  Atm my monitor controls are all on a small circuit board (on the end of the ribbon cable I mentioned) so it would be nice to house these in the box too.

I'll probably have a better look into this over the next few weeks as I have to mount my audio amp, system switchbox, USB2 hub and monitor controls in my cab since I made a few other changes meaning they're just lying around atm...I'll post back if I get it to work!

[Ken Layton]

Depending on a particular manufacturer's monitor models, some models may need shielded cables to connect a remote control pot(s) to the main monitor board. This is because an unshielded cable may introduce hum or other forms of noise/static into the signal and degrade the picture or cause stability problems.

[Minwah]

Thanks for the info

Is it important what kind of shielded cable I use?

[Ken Layton]

In general, 2 conductor shielded cable.