18
Mar
'20





So the kid complains that the indicator lights on the one side of the Opel / Vauxhall Meriva stays on all the time. This is a well known problem, there’s a dual relay and the contacts burn and stick.

So I open the box up and give her a stick and show her where to beat the relay into submission lightly tap the relay with a stick to make the stuck contact release. Problem being that once that’s done, if you then lock the car the indicators flash and guess what? Yup, bloody thing sticks again.

Google tells me you can get a new one for under 15 Sterling, which at the current exchange rate is around three hundred rands if you hurry (the rand seems to be heading south a bit faster than normal right now). But there’s shipping on top of that and it takes a while so let’s see…

<ring> <ring> “Opel spare parts, how may I help you?”

Me: “Yea hi I need an indicator relay for a Meriva,  part number 09 134 880”

Them: “Yes sir, we have those in stock, one thousand seven hundred and twenty rands”

Me: “You Have Got To Be Shi, I mean, Surely that cannot be the case my good man?”

Them: “Oh yes sorry, my mistake, make that one thousand seven hundred and ten rands”

Me: “Kthanksbyeclick”

Not being a millennial, I do have some tools and spare parts. For VERY large values of “some”. This for example is my box of spare relays.

These ones look like just the thing.

Yup, it works. Cover doesn’t fit back on again, but it will with some surgery if required. I am not too concerned.

The kid’s father is coming down from the UK in two weeks’ time and he’ll bring down the Real Thing but in the mean time this will do. Very Nicely. R1710. Fsck.

 





3
Mar
'20

Everyone knows the Fifth (symphony) and I am a great fan of the Fifth (piano) and of course the Ninth is well known but this one is new to me.

Thanks Borepatch.





18
Feb
'20

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.

 





16
Oct
'19

Look, I know back in the eighties dictionaries were maybe expensive, and many people didn’t even know they had a library.

Maar Tiffany, mase kind, this is the 21st century, het jou phone nie Google nie?





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.





5
Aug
'19

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.





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.





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.





CA 992 134. One of ours.





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