Clock Radio Hacking

Nice little clock radio with a docking station for charging a cellphone. I bought it through One Day Only or something.

One big problem, though. The display is so flippin’ bright that it keeps you awake at night. Draws moths, even. Not ideal.

The large PCB at the top holds the buttons. All the work is done by what one would have thought is the display board.

Clock, radio, everything. One would have thought they could have put an LDR in there to make the thing dim automatically when it gets dark. Philips is not what they used to be.

The 330 ohm resistor is not like the other resistors. Specifically, it’s a higher-wattage 0805 package and not 0603 like all the other resistors on the board*. Figuring that there must be a reason for this, this is where I started.

Replaced it with a 1k and sure ’nuff, the display is now bright enough to still read indoors in daytime, but dim enough to not outshine the street lights when we have them

* OK there are other 0805 resistors on the board. They bridge two or three traces, so I figured that’s why they chose bigger resistors in these positions. Also, 330 ohm is sort of the right value for an LED current limiter. Yea, it’s all gut feel. Sometimes it works.

 

When your failure detection system fails

The patient: A NAD T751 Surround-Sound amplifier.

The symptom: You turn it on, it thinks about it for about ten seconds and turns itself off.

The cause: Well, the gnomes over at NAD built in a whole bunch of self-test diagnostics into the microcontroller. If the output transistors draw too much current, or there’s DC on the speaker lines, or… anything else, really… the system shuts down. One would hope to think that it also emits an error code of some type somewhere, but if it does it’s not documented where I could find it.

So the first step is of course to check the output transistors. This… is a mission. But after taking the whole damn thing apart I came to the conclusion that the transistors were just dandy. Not the problem.

OK, a preliminary google indicates that the protection system is likely to be the cause. Dried out capacitors and the like. Looking at the schematic, the Load board is a likely culprit, so I replaced all the caps on there. No change.

A lot more googling got me this page, and Andrew’s comment two thirds of the way down is the solution. There’s a bodge factory modification on the AC3 board that looks like it checks that the AC power is present. If the capacitor (Andrew claims 2.2 uF, I had 3.3 uF fitted) is buggered, the bodge doesn’t work and the amp powers itself down.

New cap fitted and all is well. Now the question is whether I tell the customer that the T-751 can’t be fixed, and keep it… because damn it sounds good.

Bad design

The intercooler on my Golf 4 has been dripping oil for a while. Lately it also developed a whistling noise. Time to investigate.

The plastic cowl presses against the aluminium intercooler and after about 400 000km, wears right through the aluminium.

Replacing this thing is a bit of a pain in the arse. According to Haynes, the front bumper and right-hand side headlight has to come off, and that’s the way I did it. But I suspect one might be able to do the job by pulling the windscreen washer bottle instead.

If I could shoot like I drill

So I needed to drill three holes for three brackets to fix a vertical breather pipe to the outside of the wall. About a meter and a half apart, above one another.

And while drilling the second hole, a flash of sparks comes out the hole and the drill stops running.

Yup, plumb on the main feed between the pole and the DB inside the house.

And by plumb I mean plumb.

Murphy is alive and well in Globoka.

Fortunately there is another fuse between the pole and this spot. Replaced that fuse, sealed the hole with silicone, plastered over it.

So I bought a Tesla hybrid

A red one.

It’s a Type 4159 AB “Pluto” made in Czechoslovakia in the early eighties. Basically a 12V DC set, with a built-in transformer to turn 220V mains into 12V DC. This makes it nice and heavy — fortunately Turkish Air gives you 40kg baggage allowance.

They also bounce the bags quite a bit. Even wrapped in bubbles and spare clothing it still took a bit of strain. Fortunately the picture tube neck didn’t snap.

The story: we were in Prague, and it was a Sunday, and I had heard that there were flea markets all over the place, and the closest open one seemed to be Žižkov. So I got a tram ticket and headed off there.

Not as big as I thought it would be. They did however seem to have a rather large selection of lawnmowers.

Anyway, found the TV and two Metra Blansko multimeters (a PU-120 and a PU-140) for 15 euros.

The good news: It powers up. The bad news: Can’t get a station. The good news: I have the User Manual and Technical Manual. The bad news: It’s not in English.

Stoep

We’re South Africans, we need a stoep so we can braai.

Bricks are easy, you go down to the Mercator Tehnica, point at the picture in their book, and say “potrebujem dveiset” or whatever number you need and before you know it they’ve loaded them into the kombi* and you’re good to go. Pretty much the same for the cement slabs, except that we got them from the Bauhaus in Varaždin.

We used wide and narrow bricks to form little interlocks of concrete to hopefully hold things together.

But to get concrete delivered we had to go through a few intermediaries. Anton, who drives the lorry, speaks no English. We asked Branco to ask Anton to deliver two cubes. After the first cube we realised we only needed half a cube more, so we phoned Branco who phoned Anton and fortunately the message went through.

In Slovenia there’s no doubt as to who is going to do the work. You are going to do the work. Moving a cube and a half by hand is hard work.

Looks good though.

 

* We bought a kombi. T4, 5 cylinder diesel, from some farmers (really decent people) in Kranj. Transferred it at 19:00 the evening (DMV open until eight or something), got insurance at the same office, and we were good to go. Even better, when we parked the kombi and came home, we handed the plates in and they credited us with the remaining licence fees for the rest of the year, and we only have to pay licence fees again when we are there and back on the road.

 

Turkish Air

So this time we flew with Turkish Airlines, Cape Town to Zagreb via Istanbul. Quite a nice flight, in that the first leg is long and the second quite short, unlike the Ethiopian Air flight which wakes you up halfway through to change planes.

Also, Turkish gives you 40 kilos baggage allowance, which meant I could bring a mess of brass fittings and some poly water pipe and more — because a brass elbow which costs me R12 at the Muizenberg market costs pretty damn close to 12 Euros here and at a 16:1 exchange rate (this was before Squirrel caused more kuk) that’s a big saving.

But the leg room is atrocious. No seriously, if you’re like 5’2″ I will recommend Turkish, but for us six footers it’s ridiculous. I normally travel with my rucksack under my legs and my feet kicked under the seat in front of me. Not on Turkish, oh no. Only one place for the rucksack, and that’s overhead. And even then there’s no room to move.

And look at the nice menu you get. You know what? In the end it’s chicken or beef (in this case, chicken, and maybe veg lasagne if you ask nicely — we were not given the option). And the food’s worse than Ethiopian’s, which makes it pretty much piss poor (for the record, I think Ethiopian Air’s food is not bad at all, given the challenges).

Working Holiday, again

Remember this picture from last year? You should, I blog a whole lot less than I used to…

Well, it now looks like this:

The knotty pine ceiling boards are from Germany, via the Bauhaus in Varaždin, Croatia (Varaždin is actually the closest big city to us, closer than Murska Sobota).

Also in the works, new flooring (click vinyl, a bitch to work with if the surface you’re laying it on is not level (the surface I’m laying it on is not level)) and (most importantly) a shower.