A bit late to say 'Happy New Year'

Here we are almost ¼ of the way through 2015 and no comments from me... let me put things into perspective.

TCs had dropped to a slower flow and sometimes whole months would go by and nothing at all would be seen. That altered recently and I have about 7x devices to work on.
However, more and more of the TCs I am now seeing have faults that defy diagnosis. The TCs that I now see are mostly running the DELTA PSUs and the faults are odd and difficult to fix.

I seemed to predict what Apple would do, many years ago when having a rant on the Support Forum (run by Apple).

I predicted that Apple would not recall beyond the narrow band of numbers that we saw in 2010.
That they would beef-up the PSU ‘a bit’,
that they would make the electronics run with lower power requirements,
which would therefore be cooler,
which would therefore be less stressed,
which would therefore not break down so often...
and eventually a new design would hit the streets and overheating would be a thing of the past.

I was right. That is exactly what they did.

The remaining TCs now have no obvious weak link in their design. The heat from which they all suffered no longer cooks the PSUs alone, since they have been made to be more sturdy (mostly they chose to install DELTA units over the FLEXTRONICS).

With that weakest link removed from the critical chain of component failure, something else became the weakest link and boy oh boy have some vile problems reared their heads!

Occasionally in the early days (2009 - 2010), I would get a cooked TC whose fault was beyond simple diagnosis.
To analyse any electronic circuit you really need to have the circuit diagrams before you, to know what the silicon does and how it connects to other components. With the various makes of control boards inside the TCs and no help from Apple, this is a very difficult task.
Ray Haverfield et al, have done some exploration of the control boards, and the Linux like code structure and some of the commands that can be serially accessed. Doing this required very fine wires to be soldered to the control board. This is not something that could be tackled without a decent test rig and some surface contacting probes, allowing connection without soldering. For the first few hundred TC boards I worked on, I saw only 2x unfixable faults.

Now that the weakest link has moved into the guts of the TC, I have seen over 12x undiagnosable faults and this is with falling numbers coming across my workbench. The percentage of ‘nasties’ is getting higher.

I will keep going as long as anyone needs help but I hate having to tell an owner of a not-very-old TC, that I cannot fix it, because I cannot locate the fault. Even if I had located the fault, with high integration surface mounted ICs, I am somewhat stuck. I have no facilities to swap out suspect silicon and no test rig to evaluate the control boards.

In my early days at Intel, at the repair centre in Swindon, I would be diagnosing and fixing development tools (MDS800, Series II, ICE48/ 85/ 86, Floppy drives, etc. etc.) which was all through-hole mounted DIL chips. Full schematic diagrams, a good analog ‘scope, a multi-meter and you could fix most anything. Nowadays you need to be conversant with the software more than the hardware. The hardware is merely the carrier for the code and building blocks are now vastly integrated. If they go wrong, you cannot swap the silicon. It is now easier to swap the whole circuit board.

On personal matters, my life has been a bit of a struggle.
Illness (more balance problems and brain numbing ear-aches). Some blinding migraines (at the Office Christmas party) and members of my family dying and jumping the rails of life.
The difficulties of ageing parents living over 3.5 hours away is starting to get to me. I must break off every hour of driving and walk around for 15 minutes, to keep my balance in check. This can make a long journey very fragmented and seem to take all day.

My dear Mother, now 89, was seen by me at Christmas and on her birthday in February. It can be hit or miss when going to see her. The wonderful staff in the care home, never know how she will be but tell me ‘generally’ if she is OK in the morning, she will be OK for most of the day. If though, she is getting up in a rebellious mood, then heaven help anyone in her firing line.

My Christmas and Birthday visits were when Mum was being a rebel.
Her speech is halting, rambling and stuttering, simply too many strokes (vascular dementia) to keep the brain parts linked together.
The greeting was pretty clear however,
“You can go away. Go away now and never come back! I never want to see you again!”... then something would be thrown.

These visits leave my father, 88, in tears. He hates to see her this way and is feeling very lonely.
The home recommend she is not moved. Dad is about 30 minutes away from her, so he can ring to find out ‘How Jessie is this morning?’... and then only go on the good days.
Thanks goodness this has worked and Dad has had a few ‘good’ visits. He tells me all about them in sad detail. Remarkably he has accepted he is now a ‘bachelor’ or ‘widower’ since Mum has effectually exited stage left. He comes along up to York and likes to be here.

As an example of things that Dad likes... we discovered at the back of the Homestead, behind a shanty town of tumble-down abandoned huts, a rusted broken cement-mixer. With some digging and cutting we managed to extract the petrol engine, which was oily and seemed seized but intact. Long story short... it is a Villiers standing engine of about 50cc and dated from around 1948. It was in unmoving condition, but Dad applied his magic and now it runs fine! Make do and mend at its finest, and where I leaned my trade.

I will write more. Today though I must put new flow and return pipes in the roof of my house. Very low attic space, only 650mm high and tapering down to nothing at the sides, and sloping, and nowhere to stand up...

Don’t worry, be happy!

I shall... :-)