G'day Chris,



13 Feb 97 08:06, Chris Burgess wrote to Rod Gasson:



 CB>>> "Redesigning" or whatever you want to call it is
something I

 CB>>> avoid whenever possible - but occasionally it can't be helped.



 RG>> How often would "occasionally" be?   my guess - less
than 0.01%

 RG>> of all your repairs?



 CB> It varies, but it's a bit higher than that.. at a guess, somewhere

 CB> between 2% and 4%.  Sometimes I don't see one for a month, sometimes

 CB> I get three in one day...



Err, are you talking about redesigning the same thing up to 3 times in

one day, or do you have up to 3 pieces of individual equipment that is

poorly designed?



 CB> My guess is that they hire a very competent and qualified engineer

 CB> type person, pay him more than the other engineers (say $200K a year



 CB> Save 20 cents on a million selling article and the company has

 CB> broke even on the head engineer's wages - and I'd expect that

 CB> he'd be able to save them a bit more than that.



Yeah, that's why many VCR's don't have front panel controls these

days..  half a dozen switches, multiplied by millions of machines can

be quite a saving...   This is somewhat different than cutting corners

in design when the engineer knows that it would compromise reliability

though..  (ok, I guess not all engineers are conscientious  in

this regard).



 CB> Of course, this is only my hypothetical idea - I've never been

 CB> involved with big time manafacture.  After seeing a lot of faults



Me neither.



 CB> that should have never happened in the first place (one last week

 CB> was a radio being flogged as "heavy duty" to the 4WD crowd failing

 CB> due to a cracked board - 6" x 8" approx - that is only held in by

 CB> four screws.. a couple or three more screw points and it wouldn't

 CB> have happened, and would have cost the manafacturer 10 cents at

 CB> most) I can only assume things are done that way.



4 screws? Wow... thats extravagant.  

I remember the days when VCR's used to have up to 6 screws holding the

top panels, and a dozen holding the bottom.  These days, 2 screws for

the entire machine.



Screwing must be an expensive business 



 CB> Bob L would be the one to ask :)



Bob couldn't get a screw in a brothel.  ;-)



 CB>>> both "brand X" TV and "brand Y" VCR
both work fine on their

 CB>>> own, (and fine with "brand A" or brand Z")
but not with each

 CB>>> other?



 RG>> Only two such cases come to mind....



 CB> Only two?  Lucky, lucky you...



I deal in high tech equipment  



 RG>> a very common one being VCR's designed for NTSC playback won't

 RG>> work on all TV's,



 CB> I presume this only happens when playing NTSC material - or does

 CB> it happen when playing regular PAL tapes too?



Just the NTSC..   mind you some are pretty poor with PAL too.



 RG>> and the other case was a classic fuckup...  one design of an

 RG>> NEC VCR refused to show a stable picture on NEC TV's. (they

 RG>> were fine with other manufacturers sets though) .



 CB> Now that sounds more like the problems I get here :-)



Lucky you.



 RG>> The thing about VCR's is that they are so crappy and unstable

 RG>> that its a bloody miracle they work at all.



 CB> Yair - a lot of delicate looking mechanicals in there.. things



So why do so many people try to use brute force to get tapes in/out ?



 CB> like that I rarely see.  The only "moving parts" on some of the



90% of video repairs are mechanical.



 CB> later stuff I see here are the press switches behind the membrane

 CB> layer on the front panel - and the trimmer presets inside.

 CB> Even things like pots for volume etc are getting rarer... replaced

 CB> by CPU controlled attenuator IC's.



Camcorders have been that way for years.  Fortunately, these EEPROM

based presets rarely cause problems or need adjusting (when they do I

generally reject the repair, 'cos I have no means of reading/writing

to them, and the manufacturers jigs are either too expensive, or not

available to non-authorised service centres).



In many ways I've found this a good thing - back in the old days when

a camcorder had 100's of presets (well, it seems that many) they

always seemed to need adjusting or tweaking..  whether this was cos

they were never set accurately in the first place, or whether

compontant drift was responsible I don't know.. but I'm sure a lot of

it was needed because of the previous techs efforts.



 CB>>> OK, what would you do in either of these (real life) senarios?



 RG>> I'd try to redesign them so they work...



 CB> Only the first time - the second and subsequent times one knows

 CB> exactly what to attack to get it working, much the same as normal

 CB> repairs.



  Yeah...  Why re-invent the wheel that you've already

re-invented.  ;-)



 RG>> I'm a failed engineer though. ;-)



 CB> Same here - if I had to take a job designing, as opposed to

 CB> repairing things electronic, I'd be on the dole within a week...



Hmmm, now there's an idea...



Cheers,

Rod



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