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= How to make your AV system user friendly = A basic guide to setting up your system so that anyone can use it. <Paul Spencer> = WARNING = Projects included require experience with mains wiring. Do not attempt construction unless experienced and capable. Death or serious injury may result from incorrect wiring. === A day in the life of a user friendly system === What would a user-friendly system be like? * one easy-to-use remote control for all components * one button on the remote to turn on/off all components without turn on/off thumps * basic and commonly used functions don't require a lot of steps This is possible even with a system that has diy components! Some comercial equipment such as home theatre receivers, have 12V triggers, which can be used to turn on/off other components when the source component goes on/off. This is great if you have such a unit, and it has a remote control to turn it on/off. However, if you have diy components, or you don't have such a unit then you need a diy solution. Here it is: [Current Sensing Slave Mains switch] This is a kit available in Australia with 240V mains. For those with a different mains voltage, [Elliot Sound Products] have a version with instructions, and a forum for advice regarding their projects. Refer project 38 in "power supply" section. How does it work? All components to be switched are connected to the mains via the slave switch. Use a power board. Connect the AC mains of a component which can be switched on/off via remote. When this master unit is switched on/off with its remote, all components connected to the slave will also come on. === But won't I get thumps when it turns on/off? === That depends. In my system at the moment, I have no issues with turn on/off thumps. Sometimes even comercial equipment introduce thumps into a system when the power switch is activated. I find this is less of a problem with mains switches. Chip amps have built in muting, so there are no issues with turn on/off thumps. Most comercial units have muting relays. When you turn on a typical unit, there is a 5 second delay before you will hear a 'click' which is a relay activating. On switching off, you will hear another click as it disengages and power is disconnected. If it's a power amp, it may have enough power in the power supply to still amplify any signal in the system. Hence this muting relay prevents this. You can add muting to amplifiers and other components. You may require this to get your system to turn on/off in the way I'm suggesting, and you can add on such a unit either as a kit (Altronics or Jaycar), or you can follow the [ESP design]. The first thing to do is connect all your audio components to one mains switch. Leave all units switched on with their respective power switches and turn them off at the mains. Then try turning them on again via the mains. If you have no problems with thumps on both counts, then you can simply add on a power up unit. === Remote controls === There are units which cost more than your computer, and there are many units which are too basic to do the job. The best source of information on remotes I found is [Remote Central] One of the most popular remotes mentioned: [URC series]. What you want is a universal learning remote control with at least a handful of macros. Here is the remote that I use: [Zensonic universal learning remote] You can program most of the buttons to accept any function of your existing remotes. If you are clever, you can actually add on "micros" which are basically 2 or 3 functions which are learnt by the remote as if they are one function. This is a trick, as remotes aren't designed for this. You can use this trick to get a few units to power up/down together at the same time with just one button. More info on this is available at Remote Cental. === So what is a macro? === A macro is a series of functions which a remote can perform after each other. eg. press a macro button and it will turn on all equipment, set TV to video mode, select a particular source and play a DVD. They usually have a half second pause between steps, so if you have a lot of steps, it can take a while. This is where micros come in handy, as they can reduce the number of steps and make macros run faster. Remote tips and comments: * don't waste your money on expensive touch screen remotes They use a lot more power (read batteries don't last long) and require you to look at the screen - tactile buttons are preferred by most even though they aren't as impressive at first * you can learn functions to buttons which are easier to find eg. on my DVD remote there is a hard to reach button to switch dics (5 disc player)- I've placed it where it is easy to reach since I use it a lot * look for a remote with backlit keys If you like to watch movies in the dark === What about source switching? === If you don't have a receiver with remote AV switching, you can buy an affordable add on unit. I use this one: [AV switch box] I purchased mine new on ebay for less than the RRP. The better units can actually learn to switch with any signal from an infared remote. In other words, you can program it to source 2 when you press play on your DVD. This is part of what makes these units cheap - you don't need another remote control. === Are you a control freak? === I am! There it is! I said it! *disclaimer: only with my sound system! Sometimes I want to disable my system so at least the audio parts can't be used. When urges like this hit, fortunately I have a key switch that disables it all. I use a key switch! Unfortunately they can't handle the current that goes through my system. Mine can only deal with 2A, hence I use it to control the 12V power needed to control a mains relay. To make such a switch you need a mains relay which can handle as much current as you are likely to get. You use a 12V plug pack to supply DC power to the relay. The key switch will control if there is power going to the relay. Set it up so that the relay requires power to be switched on, otherwise your key will be pointless! It would be like a "security" door which unlocks itself when you are out of the house! === Is it really that bad? === In a word: YES! In the past, it was a painful routine in comparison. To turn it all on, I would switch on first my eq unit, then main amp, then I would turn on my sub amp and turn up the two passive attenuators, then the TV, video and DVD units, pressing "video" on remote. To switch sources, I'd have to get up and flick a switch. It's not that bad, but it means I didn't bother using the system as much. I had to repeat all this when powering down. If I didn't get it quite right, I'd get a loud thump ... loud enough to wake someone up after a late night movie. Also, I didn't let anyone else turn it on/off as the system was just too finicky about the order it was all done. Basically, no one but an enthusiast could live with it. To switch from TV to a DVD, I'd have to get up and switch sources, then select "video" mode, and press play on the DVD. Now I simply press play! === That was then, this is now ... === To turn my system on, I press "macro 1" on my remote and everything comes on. The TV is set to video mode automatically. If I press play on either DVD or video, either will play and souce switching will happen automatically (both audio and video switching). If I press channel up, it will go to TV mode. === Putting it all together === It might take some time to get it all working smoothly, but you won't believe what you once put up with once you have done it. My family can actually use the system now. If this ever becomes a problem, I can just turn it off with my key switch! So what do you need? * one component which can turn on/off with a remote * current sensing switch and a power board for mains switching (some receivers perform this function) * muting circuit may be required to get units to power up simultaneously without thumps * remote AV selector switch (some receivers perform this function) * key switch (including mains relay and 12V plugpack) - if you are a control freak Once you have it all up and running, you won't look back! |