Silicon ChipInstall Your Own In-Car Video - April 2005 SILICON CHIP
  1. Outer Front Cover
  2. Contents
  3. Publisher's Letter: Reader feedback is welcome
  4. Feature: Install Your Own In-Car Video by Gary Rollans
  5. Project: Build A MIDI Theremin, Pt.1 by John Clarke
  6. Feature: The Start Of Colour TV In Australia, Pt.2 by Keith Walters
  7. Project: Bass Extender For Hifi Systems by Rick Walters
  8. Project: Build A Professional Sports Scoreboard, Pt.2 by Jim Rowe
  9. Project: SMS Controller Add-Ons by Peter Smith
  10. Vintage Radio: The mysterious Monarch D671/32 from Astor by Rodney Champness
  11. Salvage It: A $5 variable voltage power supply by Julian Edgar
  12. Back Issues
  13. Advertising Index
  14. Outer Back Cover

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Items relevant to "Build A MIDI Theremin, Pt.1":
  • PIC16F88 firmware and accompanying software for the MIDI Theremin (Free)
  • PCB Patterns for the MIDI Theremin (PDF download) [01204051/2] (Free)
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Articles in this series:
  • Build A MIDI Theremin, Pt.1 (April 2005)
  • Build A MIDI Theremin, Pt.1 (April 2005)
  • MIDI Theremin, Pt II (May 2005)
  • MIDI Theremin, Pt II (May 2005)
Articles in this series:
  • The Start Of Colour TV In Australia, Pt.1 (March 2005)
  • The Start Of Colour TV In Australia, Pt.1 (March 2005)
  • The Start Of Colour TV In Australia, Pt.2 (April 2005)
  • The Start Of Colour TV In Australia, Pt.2 (April 2005)
Items relevant to "Bass Extender For Hifi Systems":
  • Bass Extender PCB pattern (PDF download) [01104051] (Free)
  • BASS Extender front panel artwork (PDF download) (Free)
Articles in this series:
  • Build A Professional Sports Scoreboard, Pt.1 (March 2005)
  • Build A Professional Sports Scoreboard, Pt.1 (March 2005)
  • Build A Professional Sports Scoreboard, Pt.2 (April 2005)
  • Build A Professional Sports Scoreboard, Pt.2 (April 2005)
  • Pro Scoreboard, Pt III (May 2005)
  • Pro Scoreboard, Pt III (May 2005)

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$ave BIG money: Install Your Own In- Now you can install your own in-car video system at a fraction of the cost of the ones you’ve seen in those fancy luxury cars. Jaycar Electronics has everything you need to put together a system for fitting a reversing monitor and/or in-car navigation system to your dashboard, or even a back-seat screen for the kids to watch DVDs, TV or playing their PS-2 on those long, boring trips. You have the choice of a rear-view “mirror” display, as shown here, or you could add a GPS unit and an old laptop computer for a highly useful “Sat Nav” unit. Both are perfectly legal to use while driving along but you cannot mount the screen in this position for “entertainment” video – for that, the driver must not be able to view the screen while driving. 8  Silicon Chip siliconchip.com.au By Gary Rollans -Car Video! T HE BASIC installation we are going to describe here is a really useful rear-view video system that takes the guesswork out of reversing 4WDs, vans, trucks and buses, etc. We’ll even show you how to extend it to cover caravans, large trailers and even semi-trailers, B-doubles and road trains! Where you take it from there depends entirely on your requirements: keeping the kids entertained on long trips with games or a mobile DVD player, finding your way around Australia (or a strange city!) with GPS sat nav . . . it really is an open-ended equation. But back to the basic system: a dash-mounted video screen and a rear-of-vehicle mounted colour video camera which gives you a much better view behind your vehicle than you can achieve with mirrors. The camera is designed for exactly this purpose, producing a reversed output so that picture you see on the screen is just like the one you see in an ordinary rear-view mirror – ie, reversed. However, if you already have a standard camera (ie, right-reading), it’s possible to use that as well. We’ll explain how shortly. Mounted in the dash, the video display doesn’t stand out as anything special . . . But press the button (left top) and it pops out, ready to be . . . The screen type There are currently three types of screen available from Jaycar: ceiling mounted, in-dash mounted and ondash mounted. The hardest thing about installing one of these is choosing which one you want to use. Each has its own merits but for simplicity, we chose the QM-3753 in-dash model. This compact unit will slip into a standard DIN dashboard slot and can be folded away when not in use to minimise attention from prying eyes. That’s pretty important these days, siliconchip.com.au . . . tilted vertical and twisted left or right for the right viewing angle. April 2005  9 as “obvious” in-car video screens can be tempting items for thieves. Apart from losing the screen, there’s all the damage created as they break in. We mentioned the reversed image before. Most screens, this one included, can reverse the image if required (it’s most disconcerting looking at a “right reading” image behind you!). If you are using a standard (right-reading) camera, this particular monitor can reverse the image by connecting one wire. But it’s more convenient to use a wrong-reading camera and a right-reading screen, because you can then use it “as is” for GPS/Sat Nav, entertainment, etc. Screen installation To install the screen, you will first need to remove the dashboard console panels to gain access to the CD-radio cradle assembly. On some vehicles, this is not as easy as it sounds because hidden screws may be used, air/heater/ air conditioner control knobs are often difficult to remove without damage, etc, etc. We’re not going to try to advise you here – there are simply too many variables. If in doubt, try to get the workshop manual for your car or perhaps ask for advice from a car repairer or auto electrician. Next, remove the assembly retaining screws. Most systems use some form of cradle – it should slide forward, enabling you to unplug the power and speaker connections and remove the assembly from the console. Before taking the assembly to your workspace, check the wires as you take them off. In some vehicles, they will be tagged, telling you what is what. But if they’re not, tag the wires as you take them off so that they can be put back in the correct places. Next, you will need to mount the video screen into the spare DIN mounting space of the cradle. This will vary from vehicle to vehicle so again we won’t go into detail here. It would be a good idea at this point to extend the video input connection. Jaycar have a cable (Cat. WV7316) specifically made for the task. This will let you easily connect to the screen once the CD and screen assembly is fitted back into the car. It might also be helpful to wrap a turn or two of insulation tape around the A/V connections while the assembly is out of the car. The tape will help prevent the connectors from being pulled out later when you are scratching around under the dash. Before reinstalling the CD player and video assembly back into the dash, you will need to provide a power line for the screen and camera. This is best achieved by splicing into the CD player’s power line using crimp connectors, rather than cutting and soldering, which makes later removal difficult. This splice should be made on the CD-player side of the fuse. If you choose to run a separate power line for the screen and camera, don’t forget to include an in-line fuse. Once the power lines are in place, you can re-install the CD/video cradle assembly back into the dashboard, plug their associated connectors back in and replace the console panels. The video input leads to the screen should be positioned where they will be easily accessible when you are ready to connect the camera cable from the back of the car. Checking the unit Before going any further, plug the video camera into the 10  Silicon Chip You’re going to need a spare DIN space in your dashboard (the black panel underneath the radio/CD in this picture hides the space). Virtually all car stereo systems these days are made to standard DIN dimensions. First step: uscrew/unclip the trim/fascia and carefully remove it, then disconnect the car radio/CD/cassette. Most have one or two plugs which disconnect everything. Don’t forget the antenna! Most vehicles these days have some form of frame or carrier which itself can be unscrewed and removed (makes life a lot easier!). Remove the faceplate covering the empty DIN space and slide the video screen into position in the cradle. Fasten the appropriate screws in place. siliconchip.com.au How do you know if it’s legal? The following is an extract from the Australian Road Rules, which apply in all states. We believe NZ rules are the same or similar. Specifically, this is: Part 18, Section 299 – Television receivers and visual display units in motor vehicles Replace the cradle in the dashboard and screw it back into position. Temporarily push the trim/fascia over the radio/ CD/cassette to make sure it still fits, then reconnect all radio cables (don’t forget the antenna!). (1) A driver must not drive a motor vehicle that has a television receiver or visual display unit in or on the vehicle operating while the vehicle is moving, or is stationary but not parked, if any part of the image on the screen: (a) is visible to the driver from the normal driving position; or (b) is likely to distract another driver. Offence provision. Note: Motor vehicle and park are defined in the dictionary, and vehicle is defined in rule 15. (2) This rule does not apply to the driver if: (a) the driver is driving a bus and the visual display unit is, or displays, a destination sign or other bus sign; or (b) the visual display unit is, or is part of, a driver’s aid; or Work out which of the radio/CD/cassette cables are +12V and ground and splice the video power cables into the appropriate ones AFTER the fuse(s). It may be that there is no ground wire as such because the radio grounds via the frame. If so, you’ll need to connect the video ground cable also to a good ground. (c) the driver or vehicle is exempt from this rule under another law of this jurisdiction. Examples of driver’s aids 1 2 3 4 5 6 Closed-circuit television security cameras. Dispatch systems. Navigational or intelligent highway & vehicle system equipment. Rear-view screens. Ticket-issuing machines. Vehicle monitoring devices. The blue italics emphasis is ours, to highlight the uses which are permitted, in moving vehicles in view of the driver. Needless to say, anything which is NOT mentioned – eg, DVDs, video games, TV, etc – is prohibited. Our advice is that it is possible you could be fined or your vehicle defected if you have a screen which is capable of displaying prohibited images while mobile, even if it is also used for driver’s aids. Sometimes, it’s necessary to run new power cables if the radio cables are inaccessible or they won’t handle the extra current. If so, it’s usually best to go back to the battery and fasten a suitable fuse/terminal block (such as this Jaycar model) to the firewall. siliconchip.com.au Therefore, if the display is fitted where the driver can view it, we would suggest a lockout system be used on the device (eg, a relay powered from the ignition switch) to prevent prohibited inputs when the ignition switch is turned on. April 2005  11 display video input, power up and check that all is OK. Better to find any problems now than later on when all the wiring is in place! Installing the camera This is a fairly simple task with the hardest part deciding where and how you wish to mount it. Some prefer to have the camera mounted inside, viewing through the back window, to give a “high” image. The alternative position is mounted inside your rear bumper – adjustable collars are actually supplied with the Jaycar QC-3452 camera for this purpose. If you decide to fit the camera inside the vehicle, you will need to find a suitable mounting position which not only gives a clear view but minimises the danger of the camera being damaged by anything moving around the back of the vehicle. You may also need to make a small “L” bracket to mount the camera or you can do as we did and mount the camera inside a Jaycar HB-6080 flanged jiffy box and use double-sided foam pads to stick the box to the roof lining at the rear of the vehicle. That way, there are no holes to drill and no damage when it comes to disposing of the vehicle, The hardest part about the bumper-mounted camera is drilling the 25mm hole in your rear bumper. It’s easy if you have plastic bumper bars; not so easy if they are steel! You will need a 25mm hole-saw to do the job. Once the hole has been cut and de-burred, you can fit the camera into the bumper and adjust its mounting angle using the collars supplied for the purpose. The rear of the camera has two orientation marks to help get the picture the right way up. To get the video signal to the front of the car and power back to the camera, you will need to run a pair of cables through the cabin. These should be tucked away under the carpets, out of sight and harm’s way. You can either make your own video cable or use a ready-made one, such as the Jaycar WQ-7224. Ready-made is the quickest and easiest option – and probably the cheapest as well. One alternative for power is to use the parking light circuit. Admittedly, this means you’ll need to have your parkers on whenever the system is in use but that’s no big deal these days – and it might make your vehicle just that much more visible. Getting the cables to the outside of the car can usually be achieved by routing them through one of the access bungs in the floor of the rear cargo area in a 4WD or the boot in a sedan. Typically, these are in the lowest areas such as under the spare tyre. Alternatively, you could use the same access bung which encases the cables to the number plate lamps or trailer plug. Once the cable has been run, you can connect the power and video lines. Turn on the ignition and check that power is available at the camera. If all is OK, turn the ignition back off and plug the cables into the camera. Now you can unfold the screen turn it on and turn your ignition on. If you have wired up everything correctly, you should have a nice rear-view picture on the screen. Road testing As soon as our newest toy was installed, we were eager to get out and see how it performed on the road. The first thing we noticed was the significantly better view of the 12  Silicon Chip The Jaycar QC-3452 Reversing Camera is especially made for our application, providing the “mirror image” picture you’re used to seeing in the rear view mirror. It is also very easy to mount – just one 25mm hole is required. The red lead is 12V CD power, while yellow is video out. Here’s the camera mounted in a Jaycar HB-6080 jiffy box (a nice, neat fit!), itself mounted on the roof of the 4WD. Different vehicles will have different mounting arrangements. An alternative is to mount the camera low down, even through the bumper bar (it is waterproof!) for an excellent reverse parking indicator. Another view of the mounting arrangement for the camera. This gives an excellent “high up” view through the rear window when the rear door is closed. The cable can be routed above the headlining and down one of the pillars for a nice, neat installation. siliconchip.com.au The “low down” camera position, inside the rear bumper, makes parking a breeze! Fortunately, this bumper is plastic – drilling metal is much more difficult. The angle can be adjusted via the use of supplied collars. Cabling can go via the rear number plate wiring “boot” or a cargo area drainage plug. It’s not hard to see why they’re called a GPS “Mouse” but there is no mouse function at all. Inside the waterproof case, here magnetically mounted on the vehicle roof, is a GPS antenna and receiver – this particular one is a USB device but there are PC card, CF, serial and Bluetooth varieties. Here’s a demo screen from one of the freeware packages we found on the ’net. There are others which offer street-level resolution but generally you have to pay for the better ones. You don’t need too much in the way of computer grunt to run them – a good use for that old laptop, maybe? siliconchip.com.au area behind the vehicle. The camera’s wide-angle lens provides a 92° field-of-view and practically eliminated the blind spots in the rear quarters. The system also provided an easy means of judging the distance to objects behind the vehicle. We had decided to mount our camera on the ceiling at the top of the rear window, in a mid-size 4WD. From this position, we were able to see the roadway as close as one metre behind the vehicle. If mounted at bumper level, the view would be much closer. Four-wheel-drives have great forward visibility but it’s difficult to judge just how close you are to objects at the back. With our new system we were able to reverse into tight parking spaces with ease and there was no doubt how close objects were. The screen was easy to see, even in full sun and needs no skill to operate. Other options There are a host of useful possibilities that can be added once the basic system is installed. These include a TV tuner or a DVD player for passenger entertainment, or even a low-cost GPS navigation system utilising an obsolete notebook computer, low-cost GPS module and shareware mapping software. You could even extend the reversing camera to a caravan by using a standard audio/video sender. If you have ever tried to reverse a caravan down a narrow driveway, you’ll know how useful that can be! Note, however, that Australian road rules prohibit any “entertainment” type video – that is from a TV tuner, DVD, game, etc, being displayed while the vehicle is in motion if the driver can view the screen. Common sense suggests this anyway – you can imagine just how dangerous it would be trying to watch a TV screen and driving at the same time! It wouldn’t be too hard to knock up some form of interlock which prevents the wrong video being displayed while the ignition is turned on. Power supply preparation If you are going to install more than one extra device in your system, it’s probably a good idea to have extra power readily available. The best way to do this is run heavy-duty cables directly from the battery – fitting a good quality distribution block such as the Jaycar HC-4020 and a suitable automotive relay (such as the Jaycar SY-4068) and matching base (SY-4069) in the engine bay is the best way to achieve this. First, mount the terminal block and power relay in an easily accessible place with metal screws and lock washers. Then run a length of heavy gauge cable from the terminal block via the relay and in-line fuse to the positive battery terminal. Make sure you allow enough extra cable to neatly secure the wire to the existing cable loom in the engine bay. The cable should be terminated with a suitable connector and already connected to the terminal block before it is connected to the battery terminal. This will prevent any accidental short circuits when you are running the cable. Power to the relay should come from the accessory side of the ignition so that the auxiliary systems only operate when the car is running or the key is in the accessory position. This is easily obtained by tapping into the supply line to the existing CD player or even the cigarette lighter April 2005  13 Par t s Lis t: Reversing Video In-dash TFT monitor (QM-3753) Reversing camera (QC-3452) Camera power connector (PP-0510) Crimp connectors (WV-7316) Video extension cable (WQ-7224) 6m length of Fig-8 cable (WB-1710) Hook-up wire, cable ties, heatshrink tubing, etc For higher capacity supply: Distribution block (HC-4020) Horn relay (SY-4068) Relay base (SY-4069) In-line 60A fuse (SZ-2065) Hook-up wire, cable ties, heatshrink tubing, etc Note: all part numbers refer to catalog numbers for Jaycar Electronics. socket, which is normally switched on by the ignition switch in most cars. When this is complete you will have a convenient point to run the power lines to from the extra equipment. Adding GPS navigation Now that you have a video screen installed in your car, there are lots of other applications. One of the easiest is an in-car GPS navigation system. Commercial units cost $1500 or more but you can cobble one together for just a few hundred dollars using a notebook computer, a “mouse” GPS receiver and free software readily available from the Internet. There are plenty of older laptops lurking around and they don’t need to be very powerful to do the job. The system described here runs on a Toshiba 600MHz Celeron but the development was done on an old Pentium 100 with 16Mb of RAM! The only reason we ended up using the Toshiba was because it has on-board composite video out, so was a bit easier to interface to the screen (ie, it plugged straight in!). But even the old P-100 worked fine with the addition of a VGA to composite converter – these are readily available from Jaycar Electronics and cost around $100. There are many ways to put this system together and once you have started to poke around the Internet, you will doubtless find a few more. The GPS receiver While this system will work with the majority of GPS receivers that have a data (computer) output, our system utilises a low cost “mouse” GPS receiver that we bought brand new on Ebay for about $110. In fact, we bought this about a year ago and it’s been sitting around waiting for a use such as this. Currently on Ebay, the same devices are selling for about $75.00 – you might even do better! There’s no screen, buttons, switches, or anything else that the dearer, self-contained GPS units have but it is perfectly suited to our task. The device consists of a matchbox-sized module with a USB (or serial) connector on the end of two metres of cable. It is waterproof and has a strong magnetic base to secure it 14  Silicon Chip to the roof of the vehicle. The unit could easily be left on the dashboard (for better security) but the roof mounting gives the receiver a better view of the sky (ie, more satellites to view) and therefore better accuracy. Be careful when buying a GPS receiver that you get one that is NMEA-compatible. Most are but for some unbelievable reason, a few recent models have gone their own way and use their own non-compatible software. If you want to use the GPS with mapping software, for example, it will almost certainly need to output using NMEA code. Also be careful about the interface between the GPS receiver and the computer. As mentioned above, most are USB or RS-232C serial and so plug straight into most laptops. Some are PC-slot (once called PCMCIA) compatible and most laptops and notebooks, even low cost and relatively elderly ones, have at least one PC slot. There are some otherwise fine GPS receivers available which are ONLY CF-slot compatible. These plug into a compact flash card (CF) slot on a PC but until fairly recently, few laptops had one of these built in. Fortunately, CF-toUSB adaptors are very commonly available and are also cheap (for example, $10 on EBAY will get you a multi-card adaptor). You can also get cheap CF to PC-slot adaptors. Installation What installation? It could hardly be easier. Simply plonk the GPS receiver on the vehicle roof, plug it into the notebook, plug the composite video output from the notebook into the monitor and load the software. OK, so you might need to add a VGA-to-composite video converter if your laptop doesn’t sport composite video out but that’s it. Software GPS software is readily available on the Internet and we have tried three different versions. Two are freeware and one has to be paid for. Two of them follow the normal Windows style with tool bars at the top of the screen and the selected map below. The third version operates under Windows but has a full screen display. It also has a number of interesting features including a speech option that gives you a commentary as you drive along, telling you how fast you are travelling, which direction you are travelling in and how far you are from your destination. The program can also be used with voice recognition software to produce a voice-driven system that talks back to you. None of these have turn-by-turn directions but this will undoubtedly be available before too long. In fact, there’s probably freeware or shareware out there which does it already – it’s just a matter of searching. All three programs we looked at allow you to scan your own paper maps and calibrate them for use with the system You can also download digital maps from the Internet SC for free. Where To Get Software www.oziexplorer.com – this costs around $110 and is locally written. www.gpss.co.uk – this site is free and has all the speech stuff. www.gpstm.com – this Brazilian site is also free (in English). siliconchip.com.au