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COMPUTERS CD Record The major components of the COMPRO CD-R kit include: (1) a CD-R drive, (2) a SCSI interface card, and (3) Gear pre-mastering software on a CD-ROM. The kit also includes two blank CD-ROMs and a SCSI driver installation disc for Windows 3.1. Creating your own CD ROMs is fast and easy with the latest generation CD recorders. And the cost is coming down all the time. Although CD ROM drives have been the norm in PCs for some years now, CD recorders have been much more esoteric devices with price tags to match. Until now that is – in the last 12 months, CD recorder prices have plummeted dramatically, placing them in reach of just about anybody. For little more than a grand, you can now choose from a range of CD recorder kits that you can install 8  Silicon ilicon C Chip hip yourself or have installed for you. Alternatively, you can now specify a CD recorder as one of the options if you’re buying a new PC. If you need a reliable method of archiving and storing (or transferring) large amounts of data, a CD ROM is well worth consid­eration. A CD-ROM can store up to 650Mb of information and this can either be added in one session or, provided the system is ca- pable of it, in multiple sessions. But while data archiving is the biggest application for a CD recorder (CD-R), there are other applications. CD-R lets you create your own audio and video CD titles, for example. Some systems even have the capability of copying tracks from an exist­ing audio CD onto your PC’s hard disc so that they can then be recorded onto a CDROM. Not all CD-R drives support By GREG SWAIN ders: The next add-on for your PC copying audio tracks however, so check carefully when buying a CD recorder kit if this particular feature is important to you. CD-R drives A CD-R drive looks exactly the same as a conven­tional (read only) CD-ROM drive and can simply be substituted for the existing unit. CD-R drives are invariably SCSI devices (Small Computer Systems Interface) and so a SCSI interface card is required. A CD-ROM is not like a floppy or hard disc drive, so it’s not just simply a matter of copying files to it. Instead, you have to use special pre-mastering software and this is normally supplied with the kit. The pre-mastering software is necessary because CD-ROMs use a different file format to DOS-formatted discs – typically the ISO 9660 standard. In practice, the pre-mastering software is used to create a “virtual image” file of the CD. A virtual image file lists all the file names and directories to be copied and contains other information necessary for writing to Because it is a SCSI device, the CD-R drive requires a SCSI interface card. This card is plugged into a spare ISA slot on the motherboard. a CD-ROM. It does not include the actual data files, however. It’s also possible to create what is known as a “physical image” file on the hard disc. This is an exact copy of all the information as it is to be The CD-R drive is slit into a vacant drive bay from the front of the computer. We disabled our existing CD-ROM drive to obtain a spare power connector. recorded onto the CD-ROM and is creat­ed after the virtual image has been created. A physical image file is usually only necessary if you have a slow hard disc. That’s because CD recording is a The free end of the ribbon cable from the SCSI interface card is plugged into the back of the CD-R drive, along with the power connector. No audio cable is supplied with the kit. D December ecember 1996  9 Creating A CD-ROM: The Basic Steps Using 1 Fig.2: type in the image filename in the space provided, then click the Create button. The image file is created and the program returns you to the workbench. Note that only capital letters, the numbers 0-9 and the underscore character (_) are valid characters for ISO filenames. 2 3 continuous process and there must be no serious interruptions while record­ ing is taking place. If there is an interruption (eg, because the hard disc can’t keep up and the data buffer empties), the recording process will be aborted and the CDROM will be ruined. You can then either toss it in the garbage or use it as a drinks coaster. Because a physical image takes less 10  Silicon Chip Fig.1: select the CD type to be created at the Gear workbench, the click the Create Image button. time to read than a virtual image, it reduces the likelihood of the buffer running out of data during the recording process. The downside is that you need lots of space on your hard disc, since all the files to be written to the CD are duplicated. The good news it that a virtual image file is all that’s required in most cases, particularly if you have a computer with a fast hard disc. It pays to de- Fig.3: click the Edit Image button to bring up the Data Editor. fragment the disc on a regular basis though, to eliminate any possible problems. CD-Recorder Kit Typical of the equipment now available in this field is the Compro CD-Recorder Kit. It comes with an internal SCSI CD-R drive, a fast SCSI-2 interface card, Gear pre-mastering software (supplied on CD-ROM), a SCSI g The Gear Pre-Mastering Software 4 Fig.4 (above): edit the virtual image using the Data editor. Just select the source drive and drag the files you want to the My ISO Track window. 5 Fig.5: click the test button on the workbench to begin a test write. Alternatively, you can bypass the test procedure and write straight to the disc. 6 driver installation disc (for Wind­ows 3.11 users) and a SCSI interface cable. Thrown in for good measure are a couple of blank CD ROMs, plus a user manual and an installation guide for the SCSI card. Our first impressions of this kit were very favourable, as only good quality components have been included. The CD-R drive is a Matsushita CW-7501 Plug and Play unit, while the SCSI card Fig.6: click Yes to automatically write the image to the disc if the test is successful or No for a test write only. is an Adaptec AHA-1520B. The SCSI card features automatic termination which means that you don’t have to worry about removing terminat­ ing resistors if a device is plugged into the external connector. The CD-R is capable of reading a CDROM at quad-speed (4x) and writing at double speed (2x). The pre-mastering software also lets you write at single speed if you have a computer with a slow hard disc drive. Unlike some CD recording kits, this particular setup sup­ports a wide range of recording formats. It’s lets you create multi-session and mixed-mode discs and it supports CD-ROM Modes 1 & 2 (ISO), CD-ROM XA (extended architecture), CD-I, CD Enhanced (also known as CD Plus), and CD digital audio (Red Book audio). A multi-session disc is one on which December 1996  11 Fig.7: a physical image can be created if you have a slow hard disc or for maximum reliability. It requires a lot more hard disc space than a virtual image however, since it makes a complete copy of the files to be written to the CD-R. Fig.8: the “show log” option lists the steps that have been taken in creating a CDROM. This can be handy if you get interrupted during the process. data has been added during several different sessions. This is useful for archiving data or updating a catalog on a regular basis, for example. When the disc is read back, the CD-ROM reader automatically presents all link­ed sessions as one. You are not aware of the number of sessions on the disc. With a multi-session disc, you can keep on adding data until the disc is full. Note, however, that each session intro­duces a data overhead of about 15Mb. This data overhead consists of track lead in and lead out information. You can also effectively delete and update files on a multi-session disc. This is done by adding (appending) a new session. During this process, the software reads back the last session and creates a virtual image of it. You then edit (update, delete or add) the file contents of this virtual image before writing the new image to disc. Of course, data is not really deleted from a CD-ROM – it’s just that there’s no longer any reference to it in the new table of contents that’s created 12  Silicon Chip when the new session is added. So as far as the user is concerned, the file is no longer there – just as if it had been deleted. One variation of the multi-session format is the CD-En­ hanced (or CD Plus) disc. This is handy when creating a mixed mode disc containing both computer data and CD audio. It lets you “hide” the audio from the data and vice versa. Under this format, the audio tracks are written during the first session while the data tracks are written during subsequent sessions. An audio player will then only detect the first session and so will only play the audio. Conversely, a CD-ROM drive will show only the data that’s recorded on the disc. Installing the hardware We chose a Pentium machine with PnP BIOS and Windows 95 as our test bed for the Compro CD Recorder Kit. Both the CD-R and the SCSI card are Plug and Play (PnP) items, so they are easy to install and get going. Unfortunately, when we opened the case, we didn’t have a spare power connector for the new CD-R. We solved that problem by disabling our existing quad-speed CD-ROM drive. Before pulling the power connector however, we booted Windows 95 and removed the CD-ROM device driver (just go to Control Panel, double-click the System icon, select the CD-ROM and click Remove). Of course, there’s nothing to stop you from keeping your existing CDROM drive if you have enough power connectors. Indeed, this would be desirable if your existing drive is an 8x speed (or higher) unit, for example. The SCSI card plugs into a spare ISA slot on the mother­ board, after which the SCSI cable is attached to the internal SCSI connector. This connector is keyed, so the cable can only be attached one way which is just as well because the COMPRO In­stallation Guide shows the colour stripe on the wrong side of the cable (the Adaptec Installation Guide is correct). The CD-R slides into a spare drive bay and is secured using the four screws supplied. It’s then just a matter of plugging in the free end of the SCSI cable and attaching the power connector. A minor niggle here is that no audio cable is included for attaching the CD-R to a sound card. This won’t be missed by most people; an audio cable is only necessary if you want to play CD audio discs. You can still copy audio CD tracks however, since this data is sent via the SCSI bus. COMPRO’s excuse is that they don’t know what kind of sound card you have but we think that a cable suitable for a Sound Blaster card should have been included. The installation guide also incorrectly shows the pin connections for the audio socket, so be warned if you intend buying a cable from your local comput­er store. Fortunately, the correct pin connections are clearly labelled on the back of the drive itself. When we rebooted the system, Windows 95 automatically detected the SCSI card and the new CD-R drive and installed the appropriate device drivers. If you don’t have a PnP system, it may be necessary to change some of the settings for the SCSI card to avoid a hardware conflict (eg, with a sound card). You do that by using the embed­ded SCSISelect utility. This Fig.9: the “Multi Session” option must be enabled if you want to add data to a CD-ROM over several sessions. The verify and physical image options are also set here. is accessed by pressing Ctrl-A during the boot-up procedure, after which you can change a range of settings, including the IRQ channel and the SCSI ID number. You can also choose from one of three termination options (Enabled, Disabled or Automatic) and disable the host adapter BIOS. In fact, Adaptec recommend that you disable the BIOS if the peripherals on the SCSI bus are all controlled by device drivers and do not need the BIOS. By default, the SCSI card uses I/O port address 340 and IRQ 11 and these are also typically the default settings for a Sound­Blaster card. If this applies to your setup, it will be necessary to change the settings on one card to avoid problems. Using the software The Gear pre-mastering software comes on a CD-ROM which in­cludes both Windows 95 and Windows 3.1 versions (versions are also available for OS/2 and the Mac OS). In addition, the CD-ROM includes a comprehensive manual on the Gear pre-mastering soft­ ware in portable document format (pdf) plus a full working copy of Adobe Acrobat Reader 2.1 (to let you view pdf files). The first thing to do after installing the software is to turn off any screen savers and anything else that could interrupt the recording process (eg, a fax modem). For the same reason, the manual also instructs you to turn off the “Auto Insert Notifica­tion” option for the CD-R drive and gives the step- Fig.10: we initially had problems with buffer under-run. Ditching the cyclical buffering option and selecting doublebuffering instead solved these problems. by-step procedure for doing this. The basic procedure for “burning” a CD-ROM is clearly set out in the manual. First, you have to choose the CD type to be created (eg, CD-ROM) and create a new image file (Figs.1 & 2) You then open the Gear Data Editor, select the source drive and drag the files you want to the My ISO Track window. If you make a mistake here, you just delete the track that you don’t want from the image. Closing the Data Editor now returns you to the workbench, at which point it is a good idea to run a test write. This useful feature does everything except actually write to the CD and is used to confirm that the data throughput from the hard disc to the CD is high enough. You can also elect to automatically write to the disc immediately after a successful test and there’s a verify after write option. Alternatively, you can bypass the test procedure and write straight to the CD. A bargraph shows the progress of the record­ing and the disc is automatically ejected when the procedure is completed (as it is at the end of a successful test run). The Gear software is easy to use although the Data Editor is a little clumsy. First, it’s default window sizes are too small and although they can be easily resized, they don’t stay that way when the Data Editor is closed. Another problem is that the folders on the hard disc are not presented in alphabetical order. That said, both these criticisms are fairly minor. Sorting out the wrinkles Our initial tests with small files were successful but we quickly ran into problems when we tried to write large amounts of data to disc. These problems centred around the type of buffering used. By default, the Gear software installs with cyclic buffer­ ing selected, as Using Gear For Data Backups A CD-ROM is useful as a secure medium for backing up data and Gear includes various archive setting op­tions to make the job easy. By enabling the archives reset feature, the software will automatically reset the archive bit for each file that is loaded into the image. Any files that are then subsequently modified or created will have their archive bit set again by DOS. Provided that the archives only feature is enabled, you can now simply drag all files across to the image when writing the next session. However, only those files that have been modified or created will be loaded and added to the CD-ROM. Those files that haven’t been modified remain in the previous session(s), thus giving a complete backup. Other options let you choose whether or not to load hidden and system files. December 1996  13 Fig.11 (right): clicking the DiscInfor button on the Gear workbench toolbar brings up this dialog box. This lets you select and copy individual tracks (eg, from an audio CD) to the hard disc. Fig.12 (below): once the tracks are on the hard disc, the virtual image for an audio CD is created in the same way as for a data CD-ROM. opposed to the alternative double-buffering option. During the recording process, the buffer stores data from the hard disc and streams it in a continuous fashion to the CD-R. If the buffer runs out of data, any interruption to the data stream from the hard disc aborts the recording process. With cyclic buffering selected, we found that the buffer initially filled (as indicated by a bargraph) but then slowly emptied during the first few minutes of the recording process. After this, the hard disc really rattled along as it attempted to keep up with the demands of the CD-R. When large amounts of data were involved, the process inevitably fell over. Once, we were about two thirds of the way into writing 600Mb of data when it crashed, despite a successful test run. On another occasion, we didn’t even get to the halfway point. We tried everything to solve this problem, including chang­ i ng the buffer size, writing at single speed and even creating a physical image of the 14  Silicon Chip files to be written. But no matter what we did, the buffer still emptied after just a few minutes and the hard disc rattled its head off. Unfortunately, initial test writes with double buffering selected didn’t hold much promise. Although the hard disc now worked at a fairly leisurely rate, the bargraph always show­ed an empty buffer which didn’t even fill before recording started. With two dead discs sitting on the table, it was time to call the local COMPRO distributor. Their advice: (1) ditch the cyclic buffering and use double buffering; (2) create a physical image of the data; and (3) record at double speed. And the empty bargraph indicator when double buffering is selected? Apparently, that’s normal; it only works for cyclic buffering (it’s just a pity that the manual doesn’t say that). And that solved all our problems. With double-buffering selected, we successfully recorded large amounts of data onto six CD-ROMs without a hitch. In fact, with our setup, it wasn’t even necessary to create a physical image file. A virtual image was sufficient, even when writing at double speed. Adding a new session Adding a new session is quite straightforward. You just insert the CDROM, click the Append button on the Gear toolbar, edit the CD-ROM image and write the data as before. The only proviso here is that the Multi Session option must have been selected before any previous sessions were written to the CD-ROM. It’s important to realise here that only the changes that you make to the image are written to the disc. If you want to keep a file, it must not be deleted from the existing image. If you do, it will appear as though the file has been deleted. Of course, you might want to “delete” files from a previous session on purpose. Each new session is added to the disc using one of several “append” Writing The Data To Tape Instead of writing to a CD, you can use the Gear software to write the data to tape. This tape can then be sent to a CD-ROM mastering plant so that multiple CDs can be produced. An unwanted by-product of this feature is that the Gear software always looks for a SCSI tape drive when it is booting up and if it doesn’t find one, comes up with the error message “No SCSI tape units found”. This doesn’t create any problems but can become annoying if you do a lot of archiving. Fortunately, it’s easy to disable this feature by editing the gear. ini file. You can do this is any ASCII text editor such as Notepad – just look for the line TapeInterface = 1 under the [tape] section and change it to TapeInterface = 0 options. Normally, for adding or deleting data, the Automatic Append option is used but there are also Manual, New and Multi-Volume Append modes. The Manual Append mode lets you select the track you want to add data to and is useful for recovering data deleted in a later session. By contrast, the New Append mode writes an empty track so that all previous sessions become inaccessible. Accord­ ing to the manual, this feature can be used to recycle a disc that has suffered a write failure (presumably after a previously successful session). Finally, the Multi-Volume Append mode is used for creating multi-volume discs. Making an audio CD The procedure for recording an audio CD is slightly differ­ent to making a CD-ROM, since you first have to copy the tracks to your hard disc. First, you insert an audio CD in the drive and click the DiscInfor button on the toolbar. This brings up the dialog box shown in Fig.6, after which you can select and copy individual files to your hard disc. A separate dialog box prompts you to name each file just before it is copied. From there, the process is almost identical to creating a CD-ROM, the main difference being that you choose CD-Audio as the CD type before creating and editing the image file. Another difference is that the recording bargraph indicates the progress of each individual track instead of the entire session. In our case, we successfully created a test CD with 17 tracks. It played back on an audio CD player just like any other CD, although we did notice a faint click between a couple of the tracks. As a point of interest, it is possible to create an audio CD over several sessions despite the fact that an audio CD is basically a single-session disc. You might want to do this if you have limited hard disc space and cannot load all the wanted tracks in one session, for example. By now, you will have gathered that the Gear pre-mastering software is extremely versatile, with a host of features – so many in fact that we didn’t have time to explore them all. Despite this, it is an easy package to use. In summary, our impressions of this CD-R kit are very fa­vourable. The complete package retails for $1295.00 and is avail­able from Rod Irving Electronics, 56 Renver SC Rd, Clayton 3168; phone (03) 9543 7877. MICROWAVE PARTS & REPAIRS WARNING!: All microwave repairs must be done by a qualified microwave technician. All text within is to be used as a guideline only. We recommend reading “MICROWAVE OVEN OPERATION AND SERVICING MANUAL” (code: MAN-MICRO, cost $19.95) for full safety instructions. Shailer Park Electronics will NOT take liability in any form for safety, health or work done. MICROWAVE OVEN LAMPS Hard to Find Range of Microwave Resistant Lamps Code Volts Watts Baseφϕ $ CL818 240V 25W 13mm $8.50 CL819 125V 25W 13mm $9.50 CL821 240V 20W 15mm $8.50 CL822 125V 20W 15mm $9.50 Base φ MICROWAVE SHORT PROTECTOR Blowing mains fuse? This short protector may be blown. It’s located across the high voltage cap which holds approximately 2300V. This short protector can be tested by first unplugging mains lead and then discharging the high voltage cap with a 1kΩ resistor. The short protector can then be safely measured out of circuit. REPLACE SHORT PROTECTOR IF FOUND DEAD SHORT. Code: 2X062H $14.95 MICROWAVE HIGH VOLTAGE CAPACITORS MICROWAVE HIGH VOLTAGE CAPACITORS Code Value Voltage Cost Is your microwave oven blowing the main fuse? The high voltage capacitor may be faulty. These high voltage, low tolerance capacitors are used in microwave ovens to complete a resonance circuit with the magne­tron which is inductive. A faulty capacitor may upset the lead-lag factor of the resonance circuit and cause the transformer to labour (hum) or blow short protector and/or main fuse. The high voltage capacitor, which holds approximately 2300V, can be tested by unplugging the mains lead and then discharging the capacitor with a 1kΩ resistor, after which it can be safely measured out of circuit. REPLACE CAPACITOR IF FOUND FAULTY OR DEAD SHORT MWC65 MWC70 MWC83 MWC85 MWC86 MWC90 MWC95 MWC100 MWC105 MWC110 MWC113 MWC114-6 MWC120 0.65µF 0.70µF 0.83µF 0.85µF 0.86µF 0.90µF 0.95µF 1.00µF 1.05µF 1.10µF 1.13µF 1.14µF 1.20µF 2300V 2300V 2300V 2100V 2100V 2100V 2100V 2100V 2100V 2100V 2100V 2100V 2100V $35.50 $36.50 $39.50 $36.50 $39.50 $39.50 $39.50 $50.50 $42.50 $44.95 $45.50 $44.95 $44.95 MICROWAVE OVEN ROOF LINING Does your microwave throw sparks inside cavity? The roof lining may need replacing. This lining is made of a special material to diffuse the microwave beam for even distribution. You will find the lining if you open the door and look up inside the cavity; it is a flat sheet held in by screws or clips. With age, the microwave beam will burn through this lining causing sparks inside. We supply 13cm x 17cm sheet, simply cut and shape to size. MICROWAVE OVEN ROOF LINING Code Type Size 13cm Price MRL20 Microwave 13cm x 17cm $15.50 MRL50 Microwave 13cm x 17cm $17.95 17cm MICROWAVE FUSES Our range of original microwave fuses are time delayed, ceramic tube, with brass nickel plated contact cups and have a high breaking capacity of 500A/500V. Never use conventional fuses as they may explode and shatter throwing pieces of glass inside the food cavity, which may be a health risk. MICROWAVE FUSES Code Rating Length Price AF010P 6.3A 5mm x 20mm $2.50 AF011P 8A 5mm x 20mm $2.50 AF012P 10A 5mm x 20mm $2.50 AF019L 6.3A 6.35mm x 32mm $2.50 AF020L 8A 6.35mm x 32mm $2.50 AF021L 10A 6.35mm x 32mm $2.50 MICROWAVE TURNTABLE BELTS Code Dimensions (A x B x C) Length Cost MWB95 95 x 7.0 x 0.6 300 $11.65 MWB100 100 x 7.5 x 0.6 320 $11.75 MWB105 105 x 4.0 x 1.0 330 $11.80 MWB110 110 x 7.0 x 0.6 340 $11.70 MWB165 116 x 4.0 x 1.0 520 $15.65 MWB210 210 x 2.5 square 650 $14.95 MWB260 260 x 3.0 square 800 $14.90 MWB280 280 x 3.0 square 880 $13.30 MWB175 175 x 2.5 round 550 $19.95 MICROWAVE TURNTABLE MOTORS Postage & Packing $3.50 SHAFT A 2.5 rpm Code: MWM91 Cost $34.95 SHAFT B 5 rpm Code: MWM16 Cost $36.95 ORDER HOTLINE: (07) 3209 8648. FREE CALL: 1800 63 8722. FAX: (07) 3806 0119 SHAFT C 2.5 rpm Code: MWM159 Cost $39.95 SHAILER PARK ELECTRONICS KP Centre, Cnr Roselea & Lyndale St, Shailer Park, Qld 4128. December 1996  15