Re: Cambridge Workstation woes - VMS 2691 PSU smoke

[Guy Dawson via cctalk]

The PSUs in the Acorn BBC Micros are we'll know for blowing caps. Replacing
caps is a standard thing when bring any BBC Micro back to life.

The StarDot forum is a good place to ask specifics about a Cambridge
Workstation - http://www.stardot.org.uk/forums/



On 30 July 2017 at 17:28, Tony Duell via cctalk 
wrote:

> On Sun, Jul 30, 2017 at 5:18 PM, Jules Richardson via cctalk
>  wrote:
> > On 07/30/2017 10:59 AM, Ian Frost via cctalk wrote:
> >>
> >> Any body any experience in fixing these old Acorn PSUs - or managed to
> >> source alternative modern supplies?
>
> In general smoke from a power supply that keeps on working is from the
> mains filter capacitors. Some makes are well-known for this. I would
> carefully examine them, they crack when they fail
>
> There will be class X capacitors between live and neutral and class Y
> between
> live and earth and neutral and earth, The former are the ones that
> normally fail,
> but I would change the lot.
>
> > Unfortunately I did trace out some, possibly all, of that PSU (most
> likely,
> > it was certainly a VMS-something in my ACW) years ago, but even if I do
> > still have the schematics, they're on the other side of the Atlantic. The
> > PSU in mine had the rectifier diode on the +12V rail go intermittent,
> so it
> > would start sometimes and not others.
> >
> > Tony D. might have schematics, but I have a feeling they weren't part of
> the
> > ACW service manual as the PSU was bought in from an external supplier and
> > not an Acorn part.
>
> I certainly traced out the schematics of mine, but I forget which PSU was
> fitted to my machine (something tells me it was made by Farnell). I can
> try to find them.
>
> -tony
>



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4.4 > 5.4

Re: C, STL, primitive languages that live on and on ... Re: Does anyone here know Siemens STL?

[Guy Dawson via cctalk]

I think timing had a lot to do with C's success.

It's a decent language and at the time powerful and flexible compared to
other languages. Universities picked up UNIX and C and taught a lot of
students. The went forth taking their skills with them.

On 16 April 2017 at 01:56, Charles Dickman via cctalk  wrote:

> There are a lot of smart people here with wide ranging experiences, so
> I like to ask questions from time to time that get more to philosophy.
> So "If C is so evil why is it so successful" was one of those
> questions.
>
> The answer I see is that it is the path of least resistance to the
> most successful outcome in the time horizon of the effort.
>
> Or, it gets the job done.
>
> Personally, I am stuck in the machine control world where things like
> symbolic names and type checking are sometimes non-existant. And I
> wonder why.
>
> SIL-3 and PLe with stone knives and bearskins.
>
> On Wed, Apr 12, 2017 at 1:48 PM, Chuck Guzis via cctalk
>  wrote:
> > On 04/11/2017 07:03 PM, Charles Dickman via cctalk wrote:
> >> The Balkanized nature of programming is interesting.
>
> > You might find more fertile ground plowing the plctalk.net forum when
> > your questions relate to the STL/SCL/FBD/LAD/CSF area.
>
> I am familiar with STL (and some of the others). My question was not
> for help. I was trying to present a contrast between the nit-picking
> the list was doing about C and that fact that a huge amount of mission
> critical programming is done in languages that are essentially machine
> code.
>
> It was a ham fisted attempt. Don't post after too many high ABV IPA's.
>
> > FWIW, "STL"  in Siemens-talk is an acronym for "Statement List".  Why it
> > isn't "SL" is anyone's guess.
>
> Probably for the same reason that PZD is process data.
>
> > --Chuck
>
> -chuck
>



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4.4 > 5.4

Re: Scrounging - was Floating point routines for the 6809

[Guy Dawson via cctalk]

That time in an open lab at IBM Austin when a newly arrived fellow Brit
announced that he had to go out and have a fag.

On 30 March 2017 at 13:18, Peter Coghlan via cctalk 
wrote:

> >
> > Or the time an English co-worker related the story surrounding her
> > initial job interval in the US.  She described the stunned look on the
> > face of the desk clerk at the local Holiday Inn when she asked to be
> > knocked up at 7:30 the next morning.
> >
>
> This reminds me of the rather surprised look on my Australian colleague's
> face when I said I was going to have a root in the cupboard for a missing
> manual.
>
> Regards,
> Peter Coghlan
>
>


-- 
4.4 > 5.4