We probably take for granted the digital display at the top of our bus, telling us what bus it is and where it is going.

Okay, maybe some of us don’t. I know many friends who still manage to board the wrong bus every now and then.

But digital signs weren’t around forever, and when the ISB system started we used more primitive route boards to indicate the route of the bus.

A large destination sign such as this is known as a “desto” in bus spotter terminology. The contrasting term is EDS, or electronic destination signage, which is the modern equivalent we use today.

As far as I can tell, the ISB system initially used some sort of long, thick rectangular blue frame. This had “NUS INTERNAL SHUTTLE BUS” along the bottom, with two empty spaces above and to the right of the wording. However, I have never seen any photos of these in service, only after they were no longer used, so I cannot confirm how they operated.

orig desto_edited

These frames were mounted in place on the bus dashboard; some survived on buses used until the early 2000s, while at least one photo indicates that they may have been reused on Science Park shuttle buses, with “SCIENCE PARK” replacing “NUS INTERNAL”.

Eventually, the system settled on large boards that were simply placed in the dashboard area of the bus. These had the route letter in the middle, the words “NUS Internal Shuttle Bus” on the top and the destination on the bottom. The font throughout was a serif font.


A1 was coded as red, A2 was yellow, B was green and C was blue. Later on, D was given a white/grey colour and BTC1 was orange.

New Route Board Designs (Reflective)

Around 2006, there were many developments on campus. SoC started to vacate its premises at Science, which meant the A information had to be edited to replace SoC with Science.

D was promoted from a supplementary service using paper in the dashboard to a full service. However, I cannot find many photos of proper D signage on the internet. It seems that most buses continued to use A4 paper with just “D” printed on it.

Update: I discovered a service board for D! It followed the “trunk route” format of A1/A2, but was black on white.

Also, Service BTC1 was introduced to connect the Kent Ridge and Bukit Timah campuses.

Since new boards were made for A, D and BTC1, NUS refreshed the design of the route boards, and printed a few paper versions of the route boards for display in side windows. The board itself was shrunk, to make it easier for the driver to flip it over, and constructed of a reflective material. The huge route lettering in the middle was changed from a serif font to Helvetica.

The words “NUS Internal Shuttle Bus” were moved to the bottom, swapping places with the destination information, which was to be made more prominent for reasons explained below.

Two Directions at One Stop

Currently, there are three bus stops in the ISB network where ISBs in both directions stop. At UTown, you have C heading to FoS or to KR Bus Terminal. At COM2, you have D1 heading to Biz or to UTown. At Museum, you have BTC1 heading to BTC or BTC2 heading to KR Bus Terminal.

The C issue is relatively recent, having started in 2018, while the D1 thing started in 2013.

However, this issue of buses calling twice at the bus stop is now new. Since 2002, B and C have stopped at E3A in both directions. BTC has called at Museum twice since 2007, and got split into BTC1/BTC2 in 2016 for disambiguation.

Hence, in addition to indicating which route the ISB is on, the route board used by the bus also has the function of indicating the direction of travel.

Historically at CP13, drivers on B would flip the board around while waiting at the stop, to display Kent Vale. A1 and A2 would continue displaying their boards.

At S17, drivers on C would flip the board after leaving the stop to display Kent Vale.

At the Bukit Timah Campus, drivers on BTC1 would flip the board after leaving the stop to display Kent Vale.


This behaviour, of stopping at the same bus stop occurs with public buses as well. SMRT, Go-Ahead and Tower Transit rely on the electronic signage to direct passengers, but SBS, which historically did not use EDS, got around the issue by having a very small number card in the windscreen which had either a red or white background depending on the direction of travel.

In the below picture, even though the signage of the 123 clearly marks it out as heading towards Sentosa, a white card is still displayed. A card with white numbers on red background is shown when the bus is heading to Bukit Merah Interchange.


Even after the shift to EDS, SBS buses continue to display that card to help commuters who are already accustomed to the system.

Back to topic…

NUS realised the importance of having the direction of travel indicated on the board, so the design for the new route boards for B, C and BTC1 diverged from A1, A2 and D.

A1/A2 and D were treated as trunk routes, so their boards’ destination areas showed a series of bus stops connected by arrows.

For the others, they were designed with a coloured reflective base area, but the top contained the destination (direction) in black letters on a white background, to highlight the destination.

Only the route letter and the words “NUS Internal Shuttle Bus” were printed on the board, in fact. As I found out from staring at the board, the white area is actually blank, with serif letters cut out and taped on!

There is also an element of ingenuity in these boards. If you observe them when they are being used, you will notice that one side of the board is framed in yellow tape.

This is because when some of our Chinese bus drivers first came in from China in 2006 (as a group), their command of English was understandably not very good. NUSSU apparently volunteered to give them English lessons, but that is a story for another time.

Since some of them would have difficulties reading the destination on the top of the board, a solution was apparently devised by NUS OED: Frame up the edges of the board with yellow tape, on the side that was displayed after the loop, when returning to the bus terminal. So the driver would simply make sure the tapeless side was facing outside for the first leg, then make sure the yellow-framed side was outside for the return leg.

This is why if you look at B, C and BTC boards, most of them have yellow tape all over the side displaying “Opp Block EA”. The yellow frame also forms the shape of the Chinese character 回, meaning “return” – the yellow tape is always framed around the side displaying the return leg.

On 10 April 2019, PA9779H was pulled into service as a spare bus despite the electronic signage not working. This made for a rather nostalgic sight, reminiscent of the Scanias’ introduction in 2010!

Paper Route Info

NUS also printed paper versions of the route boards, using the same layout, for use in side windows. The following picture shows one of them placed in the side of a Scania, but they were also placed in the side windows of coaches as well.

Another interesting shortcut to save effort was the use of A1/A2 paper signs for the rear, as drivers were presumably lazy to walk to the back of the bus to change the sign. Though this arguably defeats the whole point of the number.

Matte Half-boards

After the new Scania K230UBs came in, NUS discovered a problem with the route boards that had been used all the while.

The buses had a very deep pit in the front of the dashboard. If the route boards were placed there, the bottom half of the board would be blocked. The destination area at the top would still be visible, but the route letter was blocked and it was generally unsightly.

As such, ComfortDelGro designed a new set of boards some time after 2011 in 2013*, to be used by these buses. These were of the same size but effectively had all the information squashed into the top half. Unlike the previous boards, they had a matte finishing that was not reflective, and were printed throughout. The photo below of two boards stashed into a corner of PGP shows the difference in height.

*Since the oldest half-boards are from 2013 after the D1/D2 split, it is likely that they were introduced in 2013.

Also, around this time, D had been split into D1 and D2. D2’s boards are shown below. They continued to use the “trunk” styling; based on the information they were probably designed for the driver to turn the board around after UTown. But with no duplication of stops, it was probably not necessary.

I have not seen the D1 board. Hopefully, the destination was shown more clearly, as the destination of the bus is actually crucial at COM2. It was not.

These boards did not see much usage, however, as the Scanias were fitted with EDS a few years later.

The last remnants of their use can be seen on PA9779H, as its EDS no longer works. If you look at the picture, you can see how the board is designed to fit in the Scania.


EDS — Scania

From late 2010, ComfortDelGro began fitting EDS to the Scanias. The EDS fitted on the Scania buses have the route number listed on the left, and the destination on the right. The top line represents the destination, while the lower line scrolls through the stops along the way. A2 terminates at PGP, and the below pictures show it scrolling through PGP, Opp. HSSML, Opp. NUSS to Com 2, all stops along the route.

The exceptions are D1, which shows either “BIZ > UTOWN” or “UTOWN > BIZ”.

Later, due to stop renamings, the EDS programmers got lazier (can’t blame them, using less memory also) and replaced the entire destination area with just a big name. Thus, we saw displays like “B COM 2” and “C SCIENCE”.

I have unfortunately not been able to find the EDS model for the Scanias.

EDS — Sunlong

The Sunlong midibuses had smaller displays than the Scanias, with red LEDs instead of orange. Initially, they only displayed a single letter. Since they were used on B and C, where indicating the direction of the bus was crucial, they had to display the route boards. Luckily, they could use the old ones as they did not have the issue with the deep pit.

Later, they were programmed to show the route with the letter on the left and the direction of travel. For B we saw “ENG > BIZ” and vice versa, while for C we saw “ENG > SCI” and vice versa.

Apparently, the EDS was linked to a primitive interior display system, which would display “You are on Svc #”, visible in this video.

The EDS on the Sunlongs is a Guangzhou Tongda TD-09 Bus Line Announcer system.

EDS — Volvo

The Volvo B9Ls were introduced in 2015 and used all over the network.

The EDS in the Volvo buses is integrated into the Passenger Information System, which means that it is actually part of the same system as the next stop announcements and the next-stop display. As I discovered, they are made in Shenzhen by a company called Kabym. The model, according to this website, is a BYM-17616P8*10Y-BUS. I am not sure if it refers to the EDS model or the entire system, but the controller was apparently a Kabym NS-K.

Unlike the Scanias and Sunlongs, their EDS had the route on the right side, like public buses. If you ever wondered why, buses nowadays usually have their service numbers on the kerb side to enable passengers to see it when the bus is queueing at a stop. If there is a gap between the buses, the right edge of the EDS will be exposed.


Unlike the Scania EDS, the EDS on the Volvos did not scroll through different screens at all. Instead, for most routes, it will display a static string of text (typically wrapped over 2 lines, left-aligned) which lists the faculties (not stops) that the bus passes through.

For D1, BTC1, BTC2 and C (routes with doubled stops), the EDS showed the direction of travel with fewer words in a large font, centralised. As the EDS was linked to the GPS, it was capable of automatically changing the display upon reaching certain checkpoints; when the looping point was reached, the display automatically switched.

D1 showed either “BIZ > UTOWN” or “UTOWN > BIZ”, just like the Scanias, except with the number on the right.

BTC1 showed “KRC > BTC” and BTC2 showed “BTC > KRC”. For both D1 and BTC, the font size was originally the same small size as all other routes, but following feedback the font size was increased.

C showed “KR Terminal > UTown > FoS” and “FoS > UTown > KR Terminal” following its 2018 route amendment; it used the larger text size from the beginning.

Also, the EDS on the Volvo had a new feature: it showed “PLEASE DO NOT BOARD” in place of a destination if the bus was travelling between the penultimate and last stops, so people do not attempt to board the bus at the last stop. This was again made possible by the automatic-change feature.

The EDS used Arial Bold as the font, which was not the default font of the system. The default font made an appearance in 2017 when Service B was split into B1 and B2 and C was amended to serve IT; the EDS programmer then did not apply the change of font to Arial. A few years later (but before 2018), the font was updated to Arial.

It is also worth noting that even for the routes with left-aligned text showing the path of the bus, a left margin was added that “pushed” the text towards the centre.


Due to COVID-19, the ISB routes had to be zoned from AY20/21 Semester 1. As a result, the EDS on the Volvo B9Ls needed to undergo a mass reprogramming. This did not go very well.

In the first few weeks of the zoned ISB routes, buses did not use the EDS altogether, instead using laminated A3 papers with Calibri font. Routes that needed to show direction of travel had it in smaller letters above the route.

In end-July, earlier than I expected, some buses were spotted with new EDS controllers (Kabym AL-K80) and a preliminary version of the EDS data. This was quite rudimentary and had many issues, including an inability of CC to show its direction of travel, typos in the route details, and wildly inaccurate next-stop announcements. The route details would scroll across the screen slowly and it was impossible to take in the entire route at once.

From mid-August, two buses served as guinea pigs with technicians regularly updating and reprogramming the EDS to improve it. They slowly changed the EDS format to something resembling the original one (with text in small font wrapped over two lines left-aligned), and fixed the typos.

Finally, during recess week of AY20/21, the updated and finalised EDS programming was rolled out to all buses.

The issues with the EDS, as well as how the updated programming fixed them, are explained in detail at this post. Notably, throughout the zoning period, Arial was not used, as the default serif font remained in place.

2021- [Section under construction]

After zoning ended, the buses retained the new AL-K80 controllers. Initially, these new controllers were used to display the pre-zoning datasets, but following a series of glitches it became evident that the old datasets that were reuploaded into the new controllers were corrupted beyond usability. As such, the old datasets (with the exception of Service C) were recreated and reloaded into the new controllers and used from December 2020 to July 2021.

This reprogramming was done by the same vendor who had programmed the zoned routes. As such, these “new versions” of the old datasets used similar default serif fonts instead of the smoother Arial, and had the text aligned all the way to the left (for most routes) instead of leaving a margin. The service number was in Arial unbolded.

When the New ISB Network was rolled out on 19 July 2021, the EDS was reprogrammed again. The font used for the service number was unchanged (Arial unbolded), while the destinations had the font tweaked a little. This time, all destination-area text was centred, possibly to draw attention to the amendments since the service numbers were reused (or possibly because the instructions we gave to the EDS vendor happened to be centred…).

Services A1 and A2 featured tightly-tracked text in Arial.

Service BTC and Service L featured widely-tracked text in Arial, while other services featured text in a mix of serif fonts and Arial, with slightly wider tracking.

Due to the amendments, Service D1 was left as the only route with a duplicate stop since it was unchanged. It had its EDS text simplified to “TO UNIVERSITY TOWN” and “TO BIZ 2”.

5 thoughts on “ISB Route Signage Through The Years

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