My Rambling Thoughts

TtR trains from Little Plastic

After so long, someone finally created professional-quality trains!

Still in progress, to be delivered by end of year.

This was a Kickstarter campaign. I found it after it has closed, but luckily I was still able to join it.

It costs US$69 for a set of 5 and US$20+ for shipping.

Ticket-to-Ride trains

Trains from Ticket-to-Ride 10th Anniversary (2014). Oversized, too large for normal boards. (You can still use them if you put those that don't fit on a route on one side.)

Trains from Ticket-to-Ride: Europe 15th Anniversary (2021). Slightly smaller and can use on normal boards. US$80 + US$25 shipping from Amazon. Ouch!

I never thought about getting TtR: Europe, but I could not resist the trains.

I have been looking for custom TtR trains for a long time, but the anniversary TtR trains set a high benchmark. I've stopped looking. :lol:

3D printed TtR trains can be found on eBay, but while they have nice designs, they are too rough looking for their price.

Is mesh network inevitable?

After upgrading to an AX router, I have a gradual desire for... AX speed.

I don't really have an AX device, but I should at least aim for AC speed. And there is one essential prerequisite to get actual AC speed: high dBm. (Actually, high SNR.)

What is dBm?

It is decibels relative to a milliwatt. 0 dBm = 1 mW. -10 dBm = 0.1 mW. The highest for WiFi is -30 dBm, or 0.001 mW.

Generally:

dBmSignalEmpirical observation
-30 to -40ExcellentNear router and line-of-sight
-40 to -50Very goodIn same room and line-of-sight
-50 to -60GoodIn same room but not line-of-sight or some distance away
-60 to -70FairSeparated by a wall and some distance away
-70 to -80WeakSeparated by two walls
< -80Virtually unusableIn deadzone or outside usable range

dBm translates directly into speed, because Wi-Fi uses different modulation based on dBm.

You can find the dBm of various spots in your home by using a Wi-Fi scanner such as Wifi Analyzer by farproc on Android and walking around. There are other apps that can create a Wi-Fi heatmap.

For 802.11ac, using 80 MHz channel, 400 ns GI, at 5 GHz, per spatial stream:

dBmMCSModulationMbps%age
-519256-QAM433.3100%
-58764-QAM32575%
-64416-QAM19545%
-712QPSK97.522.5%
-760BPSK32.57.5%

So, to get the highest speed, we want to have at least -50 dBm. When it drops to -64 dBm, we get only 45% of the top speed. When it drops further to -71 dBm, it is just 23%. After that, it is not a matter of speed, but reliability.

Originally, I thought it was only necessary to use mesh networking for Wi-Fi 6E. After all, one single router at 5 GHz just barely covers my entire flat, and 6 GHz has less range than 5 GHz. But I'm not so sure now. I am currently getting -65+ dBm in the bedrooms and -70+ dBm at some spots (my almost-deadzones).

To get anywhere near AX or even AC speed throughout the flat, it is necessary to use multiple routers. I need two: one in living room and one outside the bedrooms. The objective is to get -60 dBm throughout at the least.

I don't plan to use mesh, though, just plain old Access Point (AP). I intend to connect the two routers together using an Ethernet cable.

Expected range issue for 6 GHz

6 GHz will have less range, that's physics. But how much less?

Although we normally refer to 5 GHz as a whole, there are actually two bands: one around 5.1 GHz and the other around 5.8 GHz. Obviously the first has higher range. The second is somewhat close to 6 GHz, so if we use the first few 6 GHz channels, it has similar range.

I expect I would only use 6E in the living room. This would be many years down the road, though. :lol:

Recovering Asus router LAN4 port

When using Singtel Fibre plan with ONT modem, for Asus router, under LAN > IPTV > ISP Profile, we must either choose "Singtel-MIO", "Singtel-Multi-STB" or "Singtel-Others".

The router will not be able to connect to the Internet without selecting one of these profiles.

The first two reserve LAN3 and LAN4 ports for Singtel use, whereas the third reserves LAN4 only.

We lose at least one LAN port.

What happens is that Singtel uses VLAN. Under "Singtel-Others", Internet VID is set to 10, and LAN4 VID is set to 20.

To recover the use of LAN4 port, we just need to choose "Manual Setting", set Internet VID to 10 and leave LAN3 and LAN4 VID blank.

From N to AX

I finally upgraded my Dark Knight N900 router to the Asus RT-AX82U router after 7.25 years (Apr 2014). I got the Gundam edition as it is white in color. It costs S$349, $20 more than the standard edition.

Asus now jumps from the 5x series (AX53U, AX56U, AX58U) straight to 8x series (AX82U, AX86U, AX88U). It does not have AX6x series, which is their mid-end series.

(Correction: Asus has AX68U, but it doesn't seem to be sold in Singapore.)

AX88U is automatically out for me. Other than its high cost ($529), it is also too heavy (1.01 kg). AX86U is a close contender ($419, 815g), but its vertical orientation, ironically, makes it unsuitable for wall mounting.

AX82U is not wall mountable, but it can be — with some help. :lol:

I need to wall mount my router at this spot so that the whole flat gets good coverage. My flat is split into two by thick concrete structural walls. Luckily, the AX82U is still somewhat light (740g) and the antennas can be straightened.

The AX82U is marketed as AX5400, because it can achieve 4,804 Mbps @ 5 GHz and 574 Mbps @ 2.4 GHz concurrently. (4,804 + 574 = 5,378.)

In reality, the 5 GHz number is gotten using 4x4 streams and 160 MHz channel. Most clients have 2x2 streams and support 80 MHz channel, so the data rate is "only" 1,201 Mbps, using the most efficient 1024-QAM modulation.

Likewise, the 2.4 GHz number is gotten using 2x2 streams and 40 MHz channel. Using 20 MHz channel (norm for 2.4 GHz), we get 286.8 Mbps.

Anyway, these are theoretical top speeds. The actual speed is usually 25% to 50% of them — it may be using a slower but more reliable modulation, e.g. 64-QAM.

I don't ask much of my router. I just need it to have 4 Gigabit LAN ports, support port forwarding, work 24/7 and is secure. :lol:

This is not really the right time to buy a new Wi-Fi 6 router. Wi-Fi 6E is on the horizon. It is a game-changer: it enables the entire 6 GHz spectrum. But it will take several years to get widespread support.

One router @ 5 GHz is just barely enough to cover the entire flat. For 6 GHz, a mesh network is inevitable.

Mini Multi-Storey Carpark Race Track

This is a mirrored mini-replica of Tomica's 40th anniversary (2010) Auto Parking Garage Building regular playset. This is Tomica's iconic playset.

It has a spiral car lift to move the cars up and one single spiral track for the cars to move down. The design is more ingenious than you may expect. The cars are facing the wrong way when they enter the car lift. To fix this, they will exit it after a short lift, make a C-shape turn (where the red car is on the right of the image), and re-enter the lift with the correct orientation!

There are several color schemes. This looks the most normal. (One is pinkish.)

It requires three AA batteries.

I bought it from TaoBao for 90 yuan (~S$19) with ten additional cars. (I thought I bought six more cars, but it was +10, not total 10.) There are only 8 unique designs. Later, I bought another four "sports" cars for 20 yuan.

I was ecstatic to find this! I even confirmed with the seller that this was mini-car scale. Unfortunately, when I received it, I found that it was not what I expected — the seller meant "mini" compared to Tomica's 1/64 car scale.

The scale is 50% bigger (rightmost). The seller also sells "mini-cars" (middle; four designs only), which is still bigger than what I am looking for (leftmost).

Mini Race Track (Track Games)

There are two elevators with two pretty long tracks. After the right elevator, the path makes a C-shape turn, then a jump, then a spiral and to the left elevator. After the left elevator, it makes a spiral, a long straight, then a C-shape turn to the right elevator.

It is possible for a car to miss the jump.

There is a detour for the first track to join the second. The gate will auto-swing back and must be manually set again. There is a auto-blocker after the swing gate to prevent collision if a car just happened to exit the left elevator when a car is taking the detour.

The design is incredible! Is it original or is it copied from somewhere?

The model no. is A333-180. Mine comes with ten trains, though I don't really want so many. I bought this on TaoBao for 67 yuan (~S$14 @ 1:4.80). I first saw this design around 2017, but did not pick it up until now.

For this color scheme, it is a train-only set. The seller does not allow me to change to cars. There are car-based color schemes, but they are ugly.

This requires 3 AA batteries. It can be powered by USB, which helps if you want to run it the whole day. The music (with train sounds) can be turned off.

Mini Race Track (Forest Trail)

This is a mini-replica of Tomica Mountain Drive playset.

I bought this in 2016 when I chanced upon it at Giant @ Big Box. I was very excited at first as I thought I found a new design. But it turned out to be the same as A333-170, only smaller.

It requires 2 AA batteries.

Its charm is that it is rather compact.

Mini Race Track (Airport Runway)

This is named "Airport Runway" due to its long straight track, I suppose.

There are two elevators. One track is super long, but the other is just a simple C-shaped loop.

Model no. is A333-77. -78 is Cars themed and -79 is train themed. The latter two have blue-and-red tracks.

It requres 3 AA batteries. The current verion can be powered by USB, which helps if you want to run it the whole day.

I bought this from TaoBao in 2015 with six additional cars. It costed 40 yuan (~S$8.70 excluding International shipping).

Unforunately, it spoiled in 2017. I left unbranded batteries (that came with the set) inside for too long. They leaked and corroded the battery contacts.

I thought about replacing the battery contacts myself, but since it is so cheap, I decided to buy a new one (with five cars) this year for 44 yuan (S$9).

-77 is hard to track down now. I finally managed to hunt down an old stock (no USB support) after some time.

Mini Race Track (Mountain Drive)

This is a total copy of Tomica Mountain Drive playset.

There are two elevators, driven by a single motor. This is effectively one super long track as the two elevators are connected by a super short C-shape track. Its name is very fitting as it is a long and meandering ride down. This is Tomica's best design, IMO.

It requires 3 AA batteries. The current verion can be powered by USB, which helps if you want to run it the whole day.

This is made by 俞氏兴. They seem to the only maker of mini race tracks?

(For best results, not that there are many of them, search for 赛车轨道玩具.)

The model no. is A333-170. -168 is cars, -169 is Cars theme. I would prefer cars, but it was not available (OOS?) when I was looking for it. They have the same colored tracks, the difference being sound, I think. Mine makes super loud train sounds.

I bought this from TaoBao in 2015 with four additional trains since I did not intend to buy another train-based set. It costed 46 yuan (~S$10 @ 1:4.60, excluding International shipping).

Mini Race Track (Track Racer)

I love watching cars going round and round in a loop. It is like looking at a perpetual motion machine, but it is battery powered, of course.

This mini race track was the first one I got, around 2013. This should be a very old design. I believe I've seen it even more than 15 years ago.

It has three elevators driven by a single motor. The rightmost track is a simple C shape-ish loop to the middle track. The middle track connects to the leftmost track, and the leftmost track connects to the rightmost track.

It requires 2 AA batteries.

The music was super loud, repetitive and annoying, so I opened up the casing and cut away one wire to the speaker. But it didn't become more quiet. I overlooked that the motor was very loud too.

This race track is quite complex and compact, which is why I think it has endured for so long. Car-based mini race tracks are not very popular, though. There are only a few designs available.