Toy cheetah

Preamble

A terribly badly made toy cheetah with LED eyes, and two motors to make the cheetah bound.

PCB component layout

The PCB has many issues. The PCB silkscreen legend doesn’t match the components – it is as if the PCB has been repurposed – thus, many components are either missing or replaced with different types of components – for example, where a transistor should be, an electrolytic is used instead (!!?!!). Also, some components on the PCB haven’t been labeled in the legend – these have been labelled as R98, R99 and C99. In addition, two component legs have been put in one through-hole, at least two examples of this:

  • R99 and Q4(3)
  • R98 and R4
  • R5 and Q5(3)

The main repair issue is that some wires were broken and it is not clear where they should go:

  • Motor positive
  • positive supply
  • possibly the ground

The PCB track and through hole alignment also leaves much to be desired – which makes reverse engineering it a bit of a headache. It is arranged on a rough 11 wide by 9 high grid.

The top of the PCB is actually the bottom in the photo of the tracks, above. The IC is hidden under the black blob of resin.

Wire colours are:

  • Yellow – motor1 positive
  • White – motor1 negative
  • Black – ground (this connection is not definitely correct
  • Red – positive supply 6V
  • White and white – LED
  • Red – motor2 positive
  • White – motor2 negative
  • Blue and blue – loudspeaker (top two connections on the left, direct to IC)

 

Continue reading Toy cheetah

More laundry in Thailand

Preamble

Since my last post upon the topic of laundry in Bangkok, Laundry in Thailand, some recent changes have happened in the last two years.

Previously, back in 2014, I had noted that to get laundry done you would have to go to a laundry shop, usually run by a lady, pay over the odds and go back the next day to pick up the laundry all dried, pressed and folded.

Then I had discovered, circa 2015-2016, in the residential suburbs, some houses and condos would have a random array of domestic washing machines plonked outside which could be used, self-service style, for 20, 30 or 40 baht. If you were lucky you could find one for 15 baht

Now, in 2020-2021, actual laundrettes have started to appear across Bangkok, or at least in my district, Din Daeng. They are well done too, as places to hang out and wait, with Wi-Fi and snacks and seating and tables.

However, as is usual in Thailand, the concept of catchment areas doesn’t seem to apply, and when one open a load of others will also open in the same stretch of road… thereby reducing the profitability for all concerned.

Continue reading More laundry in Thailand

Change Windows 10 Home Single Language from a US install to Thai

Preamble

Windows is awful, nuff sed…

Installed a US version… then added Thai locale (location, keyboard, regional settings, etc.)… so far so good.

However, the Windows UI was still displayed in English and trying to change the UI to Thai was a nightmare.

In the Languages settings, the Windows display language menu could not be changed from English to Thai, even though the Preferred languages list contained both English and Thai.

The Thai setting, under the Preferred languages list, had the ominous warning “Your Windows license supports only one display language

Continue reading Change Windows 10 Home Single Language from a US install to Thai