Greg Mayman wrote in a message to Roy J. Tellason:

 -=> Roy J. Tellason said to Greg Mayman
 -=> about "POWER SUPPLY" on 01-03-04  04:06.....

 RJT> Absolutely.  It's gotten me downright schizoid in terms of the way I
 RJT> deal with this technology.  There's the stuff I _use_,  and don't mess
 RJT> with,  because of things like the above,  and then there's stuff I mess
 RJT> with,  which looks to be a decade or two behind the times.  At least.

 GM> Yes, my feelings exactly.

 GM> I hate having to troubleshoot surface mount stuff.

I don't even *try* to troubleshoot surface mount stuff, it's just not economical...

 GM> A friend bought a secondhand modem a couple of years ago that would
 GM> NOT pick up the telephone line on an H1 command, but if you lifted
 GM> the phone that was also connected to the line, the modem would grab
 GM> it OK.

Weird. Last modem I successfully troubleshot was my old 1200,  a guy had
it, it got zapped,  and I was able to get to somebody at the company that
agreed with my assessment that it probably needed a new CPU chip and was
willing to send one out to me.  Not been that lucky with them since...

 GM> He got fed up with the thing and gave it to me.

 GM> I traced out the circuit of the line grabbing bit -- all surface
 GM> mount so I had to use a 3x magnifier -- and found a three
 GM> transistor circuit with a couple of resistors and a capacitor that
 GM> would act rather like a series connection of an inductance, a
 GM> resistor and a zener, to load the line in the offhook mode. 

 GM> But the odd part was a fourth transistor that would short circuit
 GM> the base-emitter of the first one of the above three if the line
 GM> was above about 20v, thus preventing the circuit from grabbing the
 GM> line.

 GM> Of course if you lifted the phone that was also on the line, the
 GM> voltage dropped to about 10v, this fourth transistor turned off,
 GM> and the other circuit could then loop the line as normal.

 GM> I have no idea why the manufacturer -- Hayes of all people! --
 GM> included such a ridiculous arrangement. I soldered a wire bridge
 GM> between base-emitter of this fourth transistor to stop it from
 GM> turning on and blocking the other circuit. Now the modem works just
 GM> fine!

Heh.  Too bad what used to be an industry leader of sorts (as in
"Hayes Command Set"!) is now gone...

Back when I was part-timing at this computer store we had one,  the guy
there says to me it needs a driver and I should get on the web and get it,
and when I tried to hit that site all I got was some stuff about the
auction they were having.

 RJT> I've not got a real good picture of what today's hobbyists are all

 GM> A quick look at a few copies of Silicon Chip magazine (Australia)
 GM> shows projects for
 GM> *  a valve (tube) audio preamplifier

I've bumped into some stuff in my travels around the net with fanatics who
still feel that it's a way to go.

 GM> *  a 350w audio power amplifier

There was a time when I'd have enjoyed that much power,  but having had
more than ample opportunity to play with stuff in that league I'm over it, 
and am quite happy with significantly less these days.  :-)

 GM> *  an IR remote controlled motorized volume control

Motorized?  No kidding.  I'd like to have a decent _simple_ circuit for an
electronic volume control of some sort that didn't involve the use of
special chips,  and still haven't found it.

About the closest I've come to that would be an abortive experiment I
started once that involved CMOS switches and pulse-width modulating
chopping the signal.  It distorted horribly,  I'm pretty sure because I
should've been using a bipolar supply and watching my signal levels more
carefully,  but perhaps I'll get back to that somewhere along the line.

 GM> *  a 0-80A LED ammeter for cars

No zero in the middle?  :-)  I've seen an article or two like that, 
before. Not a bad idea,  if you don't have an ammeter already,  though I'm
not fond of the idea of running wires around in vehicles these days.

 GM> *  an ultrabright LED torch

I've yet to get my hands on any of those "white" ones so far.

 GM> *  an efficient power supply for a 1W ultrabright LED "star"

Yes?  What would that be all about?

 GM> and that's just a three issues that came readily to hand.

Sounds like you've got a fairly decent magazine there.  The ones here have
all gone to hell,  pretty much,  with little of interest to me in them in
recent years.

 RJT> about.  I used to get the magazines regularly,  and have pretty much
 RJT> stopped doing that except for having recently started buying
"Nuts &
 RJT> Volts" again.  And too much of the stuff I've been finding on the 'net
 RJT> is at a pretty basic level,  or it's people who are doing things that I

 GM> Yeah, that's waht I've found. I discovered a couple of sites with
 GM> some electronic novelties but most of them are very, very basic
 GM> stuff.

Even basic stuff has its place,  if I want a quick circuit for something
that they happen to have.  I've built up quite a collection so far,  and
haven't stopped yet.    It started with me trying to find a
schematic for a phono preamp,  which I _still_ haven't found (it's a
ceramic cartridge turntable),  but I did find all sorts of other
interesting stuff.  If you find anything of interest,  by all means feel
free to pass it along.

 RJT> wouldn't,  like robotics and such.  I still can't get over this one
 RJT> site where the guy chronicled his spending _seven months_ to get to
 RJT> where he could cast these housings for "homebrew linear
bearings" for
 RJT> some sort of CNC machine.  Casting aluminum?  Not me...! 

 GM> Nor me!! It sure sounds like the hard way to go.

I guess he wanted to build some serious machinery,  or something.  Me, 
I'll be happy if I can get something of a "tabletop" nature going
-- something that'll mill circuit boards for me,  so I don't have to mess
around with applying resist and etching with chemicals.

 GM> Bronze is usually considered as a better bearing material, and
 GM> sintered bronze bushes aren't all that hard to buy off the shelf!

I haven't the foggiest idea where I'd go for something like that offhand. 
I do have a bunch of these nicely smooth steel rods that came out of old
printers,  and they did use bronze or something pretty close to it to slide
on those,  but I don't know that I kept any of those bits.  It'd sure save
me some trouble if I could do that sort of thing...

 RJT> True.  Although I've avoided scrapping any parts off such stuff so far
 RJT> I have once or twice been tempted to do so,  just for how small you
 RJT> could make something.  Though small isn't necessarily a big deal with
 RJT> me either. 

 GM> A friend of mine has a tiny TV set he made in Britain in about 1950
 GM> for his entry in a Radio Club competition. Apart from the p/s the
 GM> whole thing fits in the palm of your hand!!!

Heh.

 GM> OTOH watching TV on a 1-inch screen, and with no sound, has its
 GM> drawbacks 

I used to see mention of a 1-inch speaker,  and thought it'd be nifty to
have one,  for assorted little projects.  Now I have piles of
"speakers" salvaged off old modem cards and similar and don't
know that I'm going to bother doing much with them.  We'll see.

 RJT> Yes it is.  I closed up my shop back in 1992,  and at that time a guy
 RJT> who worked there had a lighted magnifier that I was making pretty heavy
 RJT> use of. I've since acquired one of those myself,  and just recently had
 RJT> to clean all the flux fumes off the lens.    There are
also a couple

 GM> I keep saying I must buy one. Occasionally I see them on sale under
 GM> Aus$100 (current price from one retailer is $99) but that always
 GM> seems to coincide with a rush of bills that I have to pay.

I think mine was around $60,  probably fairly comparable?  I got it at an
office supply place.

 GM> So I make do with a couple of hand-held glasses, and two pairs of
 GM> magnifying specs, but those big illuminated ones are just so handy
 GM> that one day I _will_ get one.

Yep.  I'm finding that having enough light makes a big difference,  too.

 GM> And they keep the flux fumes out of your face -- very important to
 GM> me these days when I have to work so close to the job to see what
 GM> I'm doing 

I have a big old blower that I salvaged out of what used to be a mini,  the
thing moves a serious amount of air.  I was thinking about one of those
flexible hoses that you normally see attached to the back end of a clothes
dryer,  with some sort of a small hood on the end to pull the fumes out.  I
just need to work out a way to stick the blower in the window,  find a
flange to attach the hose to,  and figure out a way to hang a hood
conveniently.  And rig up a remote switch to run the thing.  :-)

 RJT> OTOH on my linux box I'm running a 132 column by 60 row screen,  and
 RJT> find it quite readable.  

 GM> My guess is that you have a monochrome VGA monitor...

As it turns out I have 3 or 4 of them in the room here,  but not on that box.

 GM> those things give beautifully high definition that you just can't 
 GM> hope to match with a colour monitor.

The monitor in question is of all things a Packard Bell (!) that I picked
up at a yard sale some time back for $5!

 GM> I hope your new year is starting well, and continues that way! 

I'll do a whole lot better once I can get back to being gainfully employed
again!  Other than that things are going mostly okay...

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