Tech Flashback: BenQ QSuite v2.1

One thing that made owning a late-model BenQ DVD recorder worthwhile was the decent writing quality it had out of the box, along with the amount of tweakability the unit had. Knowing what I know now, an earlier Plextor drive (that was designed in-house, and not rebadged) was the one to die for – with its fancy PlexTools with GigaRec, PowerRec and other features, it had the widest flexibility amongst all optical drives. That being said, the BenQ DW1640 did become rebadged as a Plextor PX-740A, implying the BenQ drive was especially worthy, even if it wasn’t as great as the “real” Plextors that came before it.

Most of the tweakability for BenQ drives is controlled through QSuite, a small tool supplied with the drive and downloadable online which allows you to configure the options. In this post, we will look at all of the Qsuite functions and do some Qscans of present-day media. As far as I know, version 2.1 is the final version prior to BenQ’s exit from the optical drive business, selling their assets to LiteOn, and helping to form Philips LiteOn Digital Solutions (PLDS). In all, the BenQ and Philips joint venture lasted just four years.


On starting the program, you are warned that it only works with certain BenQ drives, and that changing settings may have side effects. It also warns you that the test results can vary, as a disclaimer as the tool mightn’t be consistent across drives and different media – it’s consumer grade hardware, not a high-end optical media analyzer.

The body of the program consists of a tabbed interface which defaults to the Information tab. When a supported BenQ drive is selected through the drop-down, the information tab allows you to view information about the drive and the disc inserted. It gives you the media code (with some bugs for DVD-R discs) but more importantly, whether the media is supported by the Media Table within the drive. Only discs supported by the Media Table within the drive (i.e. containing a write strategy) are likely to give consistently good quality burns.

The next tab is used for changing the Book Type of discs written by the drive. This is necessary to make DVD+R/RW discs more compatible than DVD-R discs by setting their booktype bits to appear as a pressed DVD-ROM. Earlier writing software were not aware of the commands necessary to control the booktype, and thus this provides an ability to set the preferences on the drive itself. DVD+RW discs can be booktyped to DVD-ROM as well, but doing so can prevent some software from writing to or erasing such discs, so the bottom part allows for the booktype of a DVD+RW disc to be rewritten.

The QScan tab is by far the most important of the suite of tools. This is a tool that allows you to gauge the physical construction quality of the disc in terms of tracking and focus error. Through a process of simulating writing at a given speed, the TE and FE are plotted versus a set criteria to judge whether it is advisable to record a disc at a given speed or not. The process does not consume the disc and does not record anything to the disc. It can even be carried out on a recorded disc, but is only effective for DVD±R (and DL) discs. The test has a setting for the test speed, as well as the sampling rate. Even with it set to full, the tests are much quicker than an actual burn as it takes scattered point-samples instead of continuously evaluating the TE/FE.

After running the test, you will get a recommendation as to whether the disc is suitable for writing at a particular speed or not.

Tests done at 2.4x seem to run into a problem and never finish, causing the drive to drop off the IDE bus as it takes a long time to complete some action “on its own”. As a result, the message above may appear. Because the QScan tool is so useful, I will look at it in a separate section below.

WOPC, short for “walking optimum power control”, is a strategy that allows the drive to pause writing from time to time to check the write quality and adjust the laser parameters to attempt to maintain writing quality. This process increases burn time slightly, and can cause some step variations in the writing quality of the disc, but generally helps keep burn quality consistent. In the cases where it doesn’t help or a faster burning speed is desired, it can be disabled.

OverSpeed is an option that lets you burn 4x or 8x media at 8x or higher speeds. By default it is turned off, but the BenQ DW1640 generally has excellent overspeeding properties and can write a wider variety of older media at higher speeds.

Part of the reason for its excellent overspeeding capabilities is the Solid Burn algorithm. This is a technology that uses the inner and outer test areas of the disc to optimize the write strategy prior to the burn starting. Optimized parameters are stored in the EEPROM and improved burn-to-burn. As a result, even unknown discs with no write strategy support can see a decent burn on these recorders. Solid Burn is generally unnecessary for discs which have media table support, but I find burn quality to be improved with it left on. Its use is not without drawbacks, which I will elaborate in a future posting. In case the drive’s self-learning features have been led astray (e.g. by mixing discs with “faked” media codes with genuine blanks) and the burn quality is problematic, the clean tool can reset the learning data to allow the drive to start fresh. This technology now exists in LiteOn’s HyperTuning/Smartburn, although traditionally with most drives, only low speed recording is possible for unsupported media with absolutely horrible quality.

For changes to these settings, they can be made temporarily (i.e. in the burner’s RAM) or persistently (i.e. in the EEPROM). The software allows you to make this choice to avoid unnecessary writes to the EEPROM which could shorten its lifetime.

The Test Write tab turns on a “simulation mode” for the drive, ensuring that no write actually occurs. In the CD-recorder days, a specific command existed to allow for simulated writes – this allowed for testing to ensure the source was fast enough to prevent buffer underruns, to ensure the laser could follow the disc’s track during recording, and to ensure the recording software didn’t encounter any errors to prevent wasting a disc. This specific command did not carry over to the DVD era, and thus in many cases when a simulation is attempted, a drive will actually burn a disc. This allows you to run simulations anyway, by disabling the drive’s ability to write, so you choose to write a disc as normal in your software to run a simulation. This does have a danger that you could inadvertently leave it switched on, and thus not burn anything you thought you were burning.

Aside from the ability to save screenshots, that’s basically all the QSuite has within it. Further drive capabilities are available with third party software – something we will look at in a later post.


I decided to run a bucketload of QScans on my DW1640 with the blank media I still have in my possession to demonstrate the advances in disc TE/FE with improved manufacturing for higher speed discs. High speed burning is enabled not only by more sensitive dyes, but also with better physical disc construction in terms of precision centering, balance, track definition, warpage, etc. With Over Speed enabled, the drive is able to run TE/FE tests at 16x, 12x, 8x, 4x and 2.4x (or 2x in the case of DVD-R). I suspect the display of 2.4x for DVD-R is merely a bug with the software that was never corrected. Of course, good QScan results do not guarantee good burn results as the laser power and waveform need to be correct to get a good response from the dye, but a poor QScan result generally guarantees a bad burn as the drive will have problems even getting the laser to the dye properly. The results will vary subtly from disc to disc (depending on manufacturing variance) and from drive to drive (in case of wear, or different models).


The oldest disc in the collection is an MCC00RG200, which is a Verbatim branded 2x DVD-R which is media code supported by the drive. The focus error is high for 16x and 12x, but tracking errors are not too bad at 12x. By 8x, with the exception of a spike of FE, it seems possible to track the disc accurately. At 4x, it seems absolutely fine, which matches my previous experience of overspeeding these discs to 4x with absolutely no problems at all. Interestingly, the FE gets worse at 2x, which may have to do with mechanism resonance or some other effects.

Another old sample is an LGE04, an LG branded 4x DVD-R that is not natively media-code supported by the drive. This disc shows universally high FE and TE values at 12x and 16x, only settling to mostly within thresholds at 8x. It’s only completely within thresholds at 4x, and looks excellent at 2x. So it seems that over-speeding on this disc might not be that advisable, but 8x may well be achievable. It also shows the variation in blank disc quality from vendor to vendor – even if it is a “higher speed” rated blank.

I managed to dig out an old CMCMAGAF1 4x DVD-R, sold under the Imation branding and supported by the media table of the drive. Like the LG disc above, the TE/FE readings are wild and elevated at 16x and 12x. By 8x, it settles down with the exception of the inner radius which seems to be high regardless. At lower speeds, a spike in the FE appears which may be a disc defect, and the BenQ does not “pass” the disc at any speed, although it seems 2x may be the safest bet.

The next-generation version of the disc is the CMCMAGAE1, an 8x DVD-R under the Shintaro brand and also supported by the drive. It has a slightly less purple coloured dye, but more importantly, this one has much improved TE/FE figures. It’s probable that burning at 12x may be safe.

The next sample is an MXLRG03, a Maxell branded 8x DVD-R also natively supported by the firmware. Maxell have had quite a positive reputation in the community for good quality media, and this shows as the media only just exceeds on TE at 16x, and seems possible to burn at 12x without issue.

The newest is an MCC03RG20, sold in a bulk spindle of printable discs rated for 16x. This disc is also natively supported by the firmware. While it is claimed to be 16x capable, it seems the FE/TE exceed limits at the outer edge when burned at 16x, so restricting to 12x seems advisable. This is not uncommon, as with most burners, using the maximum speed is often a bad idea.


The oldest +R disc I have to hand is a RICOHJPNR02, an 8x DVD+R under the TDK brand, natively supported by the firmware. While the previous generation R01 4x discs did well for overspeeding, my experience was the R02 wasn’t especially great towards the outer edge, and the graphs seem to show this. I suppose if you don’t fill the disc, you can get away with 12x or 16x, but best to stick to 8x.

Another 8x rated disc is the CMCMAGE01 which I also got under the Shintaro brand, also natively supported in the media table. Unfortunately, this one has rising TE/FE towards the outer edge, making overspeeding not recommended.

The latest discs I have are the MCC004 16x rated DVD+R discs under the Verbatim label, also present in the firmware media table. These seem to have a bit of a spike in TE about 5% in, but it seems that 12x burning may be possible, with 16x a bit of a stretch at the outer edge.


Due to a bug in the software, all of the DVD+R DL discs are claimed not to be supported by the media table, but through other means, it was determined that all tested discs were indeed part of the media table. The oldest is a 2.4x rated RICOHJPND00 branded under the TDK label, where no overspeed was offered. The test showed some spikes in TE/FE but it generally was within limits.

The next-generation was a RICOHJPND01 8x rated disc also under the TDK label. This disc showed higher TE on L1 versus L0, although FE remained relatively constant across both layers. Burning at 8x looks borderline based on the TE results, but probably not impossible.

Next-up is a RITEKS04 under the Laser Co brand of Bulkpak. This is another 8x disc. This disc shows a pronounced increase in TE towards the layer-change point at the outer edge of the disc. While overall TE is lower, the spike at the edge suggests problematic burn quality at 8x at the edge, so best to run 4x or less.

Finally is a MKM003 of 8x rating from Verbatim, which is considered a quality media. Contrary to the other discs, it seems that FE is an issue at 8x, with some pronounced TE spikes (as noted in other MCC discs as well). Burning at 8x is probably possible as the exceedance is limited, but not recommended.

Does it work on a BenQ DW1650?

While the DW1640 was my favourite drive, I have been gifted a “new-old-stock” spare OEM DW1650 with a newer Philips chipset. While I’ve dabbled with the DW1650 and found it slightly inferior, I never checked to see if it could do a QScan. I’m happy to report that it works practically the same as the DW1640 although it seems 2.4x selection is unavailable for most media.

Here is a scan of another sample of MCC 004 which shows a similar peak in tracking errors about 10% and 25% of the way in, which seems to be a peculiarity in the batch of Verbatim 16x DVD+R discs that I have. According to the tool, it’s not suitable at any speed due to the spike in TE, but generally speaking, burning at the full 16x is overly optimistic, and 12x is probably going to end poorly.


QSuite was an important part of making the most of your BenQ DVD burner. While the burner generally had good “default” choices put in, the software had the ability to change these options if you wished. The main attraction was the QScan feature, which allowed you to assess the physical construction quality of a disc through measurement of focus and tracking errors at simulated write speeds without writing to a disc. It even worked on already recorded discs (although results can vary slightly after recording). This could save you coasters from being too optimistic with your write speed choices. The majority of the software was demonstrated with a DW1640, although a DW1650 with a slightly later Philips chipset was also used and found to work just fine.

As for the media, it seems that higher speed discs universally showed better TE/FE values, as necessary to ensure quality burns. This implies the manufacturing of the discs were improved along with the dye formulation to make high speed recording a reality. That being said, some of the older media were surprising in its TE/FE stability – a look at the Maxell 8x DVD-R or the Verbatim 2x DVD-R shows that not all older discs were as “wobbly” as the others. That being said, the newest discs still didn’t give perfect TE/FE values towards the outer edge, which probably represents a limitation with the mechanism of the burner combined with the difficult physics problem of keeping the outer edge of the disc in perfect tracking and focus.

Of course, the drive is capable of even more interesting things which I will look at in a follow-up post, but interestingly, FE/TE scanning ability was present in some LiteOn drives which were supported by DVDScan, although it seems that firmware hacking has hit an all-time low with the irrelevance of optical media, lack of willing hacking expertise and the encryption/restriction of firmware distribution all playing a part in making this a thing of the past.

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Repair: BenQ DW1640 DVD±RW Drive Tray with Chinese Belts

In an era where IDE and DVDs have been left behind in preference for SATA and Bluray, it might seem strange that I’m choosing to repair my retail BenQ DW1640 DVD±RW Drive. Like many optical drives of any vintage, the rubber belt that powers the tray has degraded much like as what happened to my Bluray player. This time, I was going to replace the belt entirely and do the job properly as this is a drive that I am very fond of for a number of good reasons.

The Drive

My first DW1640 was a retail model that I asked a relative to buy for me from Hong Kong and bring into Australia. Strangely enough, I eventually came to own four DW1640s, with the remainder purchased locally as “OEM” drives without the fancy bezel, some of which have failed and been disposed of. Despite this, my first DW1640 was still the best of them all for burn quality and high-speed burning/ripping stability, and was quite affordable.

Despite BenQ being a subsidiary brand of Acer, the DW1640 was a big break from their (normally) rather unremarkable and pedestrian peripherals. My first DVD writer was a “plus-only” BenQ DW400 which was very plain but fared well for about half a year. It then succumbed to laser failure and owing to a lack of replacements, I got an upgrade to a LiteOn SOHW-812S which had its own benefits and drawbacks. Despite this, it seems BenQ DVD writers had a good reputation and the DW1640 was where a combination of BenQ-exclusive innovations came to fruition. As a result, it won CDRinfo’s editor’s choice award.

The most obvious when looking at the drive was their dual cooling system – the channels on the top of the lid are part of a system that helps funnel heat out of the drive while remaining (somewhat) dust resistant and quiet, all without the need of a dedicated cooling fan such as in early CD-recorders.

The other counterpart to it can be seen on the right side where a set of holes allow for heat to exit the drive through the side. Of course, there are a number of other nifty features which you cannot see.

Possibly due to the different top-lid design, they decided to label the drive on the underside. The drive is dated 14th May 2005, and shipped with BSGB firmware. The final version released was BSRB, showing quite active firmware development throughout its lifetime.

On the rear, everything is as regular as with most IDE optical drives with SPDIF, analog audio out, master/slave/cable-select jumpers, IDE interface and 4-pin Molex power connector.

The drive has survived being transported between a number of computers, and even survived a minature flood. The case has rusted in some spots as a result. Undoing four screws allows the rear plate to be removed, where a few thermal pads are installed to conduct heat to the drive casing as a heatsink.

The drive itself is based around a Philips NXP PNX7860E chipset. To continue disassembling the drive requires an emergency eject with a paperclip, so as to remove the front fascia panels.

It’s at this point we can see the belt and wheels – there’s some discolouration which may be due to the rubber losing its elasticity and degrading. The kink in the belt shows that the period when it was stored without use has caused the belt to permanently deform. If the tray has enough clearance, it may be even possible to use some needle-nose tweezers to do the replacement without disassembly, but I decided to tear it apart first.

The lubrication on the tray end looks fine – hidden labels under the tray are not uncommon.

The upper lid has the spindle clamp kept captive within it, as is common for PC drives.

The remainder of the mechanism is built around a plastic frame. While it’s not obvious, we are looking at the special lens focusing mechanism which is (supposedly) better at steering the beam and compensating for disc warp. We are also looking at the turntable spindle clamp mechanism which has been designed to be more precise.

To fully release the tray, a small tab needs to be pushed down, then the tray can be completely slid out.

The offending belt is a much longer belt (about 138mm circumference) than the average drive has (which is about 80mm circumference).

The Cheap Belts

In my search for belts, I found some listings on eBay for individual belts, but at fairly high prices but of an inappropriate dimension for this particular drive. As a result, I got desperate and decided to cheap-out on belts, ordering a “60+ mix 1mm square belt 40-130mm” packet for just AU$1.89 including postage. It was so cheap that I didn’t care much if it was going to work or not.

When I received it, the package smelt heavily of rubber. This suggests that the stuff is probably not particularly high-quality or stable in the long term. It came in a sealed clear plastic bag with a product information card in Chinese that had not been filled out at all.

A barcode inventory label was affixed to the other side.

The belts came in about five different sizes (roughly sorted). The number of shorter belts seemed to be higher than the number of long belts. I didn’t count the number – for AU$1.89, it was cheaper than even ordering just one belt from some other sellers.

Unfortunately, the quality of the belts did vary, with the belts being rather under-dimensioned for thickness, and some belts being thinner than others with occasional rough edges.

I took one of each size, cut it and measured the length of the belt unstretched. It came out to 84mm, 109mm, 177mm, 248mm and 260mm (circumference). Many times, the belts are specified as their half length, which is more like 42mm, 55mm, 89mm, 124mm and 130mm. Unfortunately, the smallest ones are a bit too long for most optical drives which need about 40mm half-length, and the slippage results in it not working properly. In the case of my Philips Bluray player, none of these belts proved helpful.

But I’m glad to report that I did manage to get a belt to work with my DW1640 – namely a stretched one of the smallest size, as the 109mm (while expected to work) stretched too much when in use and slipped. The smallest one is a bit tight, but it does work, so that’s better than having to get the emergency-eject-paperclip every time.


The BenQ DW1640 is a special drive that holds a place in my heart. As a result of trying to fix it, I found a very cheap packet of rubber belts from eBay and decided to give it a go. While it did fix the problem, the belts themselves were not quite correctly dimensioned and they smelt very rubbery, which suggests to me that they might not last too long in service. It’s still nothing to complain about, but I hope to be able to show why the DW1640 is such a special drive in some follow-up posts.

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Tech Flashback: Telecom Australia 600-series Adapters & Extensions

In the present day where landlines are a dying breed and mobile telecommunications has become ubiquitous, the beige-cream coloured Telecom Australia 600-series socket remains a common sight in Australian households. While I have no idea when the 600-series socket came into common usage, it would have likely existed around the same time (or even before) the inauguration of Telecom Australia in 1975, making it over 42 years old.

A Telephone Extension Reel

When I was young, these telephone cord extension reels were quite popular and could be bought from any variety shop for a reasonable price. Similar in concept to a power extension cord reel, these were fitted with a 605 plug on one end and a 610 socket on the body of the reel. The reel had about 10 meters of flat telephone cable. The design with the holes mimicked the design of a rotary pulse dial of a telephone of the era. The whole unit was the same “beige” colour that typified telephone accessories, and was clearly labelled with the Telecom Australia Authorization Number of C85/1/45. As it was illegal to connect unapproved devices, this was a necessary marking to demonstrate to the consumer that the accessory was approved. Despite being fitted with Australian 600-series sockets, the unit was made in Hong Kong. This one was actually ours and had survived a number of house moves.

The 605 plug can be seen to have three blades with two contacts per blade. A wider non-conducting spigot is provided. As the extension leads are intended mainly for temporary use, the spigot has a “filled” core – some others intended for semi-permanent installation had a hole, allowing a screw to be fitted in the mating 610 socket to hold it in place. The plug itself has an approval RA85/121 as well.

Removing the single slotted screw allows the cover to pop off. Six contacts are clearly visible, to which three lines (each requiring a pair of connections) could be connected. That being said, only contact 2 (tip) and 6 (ring) are carried by this extension lead, which will limit the functionality of some devices, as noted later in the section on Mode 3 Adapter. The configuration of connecting 2 and 6 is most common, and is the minimum necessary to support Line 1 operation.

The design of each of the blades is quite simple – an insulating plastic form has a channel in which the contact pin sits. The end of the pin is flared out, to allow a crimped spade connector to be connected to. The whole pin-form-pin sandwich sits inside a cut-out in the socket, across a channel at the bottom which prevents the assembly from sliding back into the plug. It’s likely that this is a later design, owing to the thin profile of the pin contacts.

A partner 610 socket is used in the centre of the reel, but as I didn’t want to disassemble the reel and risk breaking it, I didn’t take any photos of it. The concepts are easily conveyed with the next few adapters.

Telecom Australia Mode 3 Adapter

A Mode 3 adapter is not something that is too often seen, but when it is, it is often incorrectly mistaken as a double-adapter that doesn’t work. On a recent trip to a local thrift shop, I came across these.

These are Telecom Australia branded accessories, item number 557/3, still in its original packaging. This really speaks back to the days where you’d rent a telephone from the telco. I like the tagline – “The Vital Connection”. The adapter is used to connect various types of communication equipment (Viatel terminals, older fax machines, alarm diallers, answering machines) which have a special Mode 3 connection. This type of connection passes the telephone line into the equipment through the line 1 terminals, and returns the line through the line 2 terminals. This allows the device to “pre-empt” any downstream devices and take them off the line, so as to seize the line without any potential interruptions, similar to how a dial-up modem may have a line and (switched) telephone socket. This is “neatly” packaged into an adaptor, for where a Mode 3 socket doesn’t already exist and Mode 3 functionality is desired.

It comes with a fold out instruction leaflet which details how to install the adapter, including the potential issue of meeting a semi-permanently installed plug.

The adapter is in the beige colour, as expected. The front has the Telecom logo, the rear has the text describing the function.

The adapter has a subtle, tapered shape. Some others were more angular, but I suppose this could be a hint as to its age. Each of the blades has a rounded profile with a large contact area.

A closer look at the front shows that the spigot has a stepped profile. I believe this was to key the connection to avoid inappropriate connections, although I’m not particularly clear as to how that would work.

Support for this is seen on the “input” side of the adapter. Notice the spigot holes are different shapes for the two ports. The lower port is used for the telephone, the upper port is used for the Mode 3 device – inserting them in their correct sockets is vital for correct operation.

The unit can be disassembled by prying out the front cover.

Internally, two different types of pins are pushed into the plastic holder.

Two of the pins at the ends are of the sort that I will term seriesing pins. For the upper device, it has its pin 2 and 6 wired connected directly. The pin 1 and pin 5 connect to pin 2 and pin 6 of the lower device. The lower device has its pin 1 and pin 5 connected directly.

This has the effect of routing line 1 through the upper (Mode 3) device, which returns the line through line 2 connection which is then given to the lower (telephone) device. The completion of the connections to the telephone allows the telephone socket to also work on line 2 connections.

To facilitate the downstream telephone working on Line 1 while no Mode 3 device is plugged in, the contacts for pin 1,2 and 5,6 can be bent toward each other so they short together when no device is inserted. I presume the device may have been designed in this way, but whether the springs have retained their original position is not known.

The pin used for the middle connection is what I term a straight through pin. This basically has things parallel wired. This means that line 3 connections are duplicated to both devices in corresponding fashion (i.e. pin 3 to pin 3, pin 4 to pin 4) without interference.

It can be seen how this lends itself to easy production of double adapters and Mode 3 adapters through the use of similar parts.

If this adapter was plugged onto the end of the extension lead above, it would work just fine with the exception of having no line 2 or 3 service. However, if this adapter was plugged into the wall, and the extension lead above was used to connect a Mode 3 device, then everything breaks, because the Mode 3 device will attempt to return the line via the line 2 connections, which are not wired through on the cable. As a result, a four-core extension cord with line 1 and line 2 wired is necessary to extend a Mode 3 device (assuming it doesn’t use line 3 at all).

AWA Telephone Double Adapter

In a case of being in the right place at the right time, I found this in the same thrift shop in the same pile. I suspect they may have come from the same place, but this one is branded AWA (another bygone Australian brand). This is a double-adapter intended for connecting two telephones to a socket. Note how as a third party brand, it displays the necessary authorization numbers (C87/1/252). In this case, all the instructions are shown on the rear of the package, but note the similarity of the font between this and the adapter above.

This adapter has a hole through its spigot, allowing for semi-permanent installation. This has an AWA logo moulded into the same place as the Telecom logo was in the above (which implies the same manufacturer may have been involved). Because it is a double adapter, there is no distinction between the two outlets, both of which have a square spigot hole.

It should come as no surprise that it comes apart in the same way and consists of three straight-through modules, duplicating each pin in perfect correspondence.

RJ12/RJ45 Adapter

The RJ12 adapter is a common device which is often found bundled with any telephone, modem, fax machine sold in Australia. The RJ45 version is a little rarer. This one I found “dumped” outside during a council clean-up, so I decided to take it home just to take it apart.

Being a much more modern device, the full plug body is now omitted, and no screw is provided as the adapter is glued shut. An Austel approval is present on the side, and the pin for line 3 operation is omitted entirely as well.

With cost-reduction in full swing, the contacts for line 2 are omitted as well, making this a line 1 only adapter – the most common type and sufficient for most uses as the RJ12 connector is rarely used for two or three-line service.

The adapter itself accommodates an RJ45 style plug natively, but works with RJ12 plugs through a reducing sleeve. Only the centre two contacts are used.

The construction follows very similar principles to the wiring in the extension lead, with some corrosion appearing on the lower pin. This is probably because it had been exposed to water or chemical vapours in the past.


It’s interesting to think how we ended up with this “odd” connector that isn’t really used anywhere else (to my knowledge). Despite being a British “outcrop”, we could have just as easily adopted the BT socket just as New Zealand (across the pond) did, but we didn’t. This may have something to do with the Postmaster General or Telecom Australia’s commercial interests. That being said, the US RJ12-style and RJ45-style sockets eventually became the preferred means of telephone device connection, being more compact, cheaper and quicker to terminate but also pesky with the tab that likes to snap off.

Despite the old appearance and the limited market, it seems that the 600-series connectors will live on in some households as RJ12 adapters are ubiquitous, and the landline may be used to supply VDSL2 services over the new “mixed-technologies network” NBN that has been a disappointment all round. That being said, I don’t think such old connectors are optimized for impedance or high frequency operation, and all those connections would only serve to impede the connection quality, so maybe it’s a good idea to change over your wall plates and get rid of the beige.

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