12 Jan
2003
12 Jan
'03
5:26 p.m.
At 23:25 12/01/2003, you wrote:
the
Dunno about that, I know Tandy were subsumed into Carphone Warehouse, maybe
Maplin got the cheapo hifi bit?
since
I don't do that much programming, but I know where gcc is :-)
Yeah, but gcc lives on the computer, thus the furthest away it can ever get
is a few button presses... My soldering iron (& assorted accessories) seem
to have a life of their own, and find their way into all sorts of places...
Definitely. I tried it with a couple of 3rd party ROMs out, but neither
made a difference, so I don't think they're part of the problem. Or, if
they are, it's an upstream problem to the one that's currently afflicting
the machine. My further assumption is it's definitely a bit of silicon
that's gone wrong, rather than anything on the power side.
Unfortunately, I still don't have an EPROM burner/eraser, so even if it is
a ROM that's gone funny, I can't do anything about it yet. Any ideas for a
suitable model of device - ideally one which is relatively easy to use, can
burn different sized packages, and will connect to a Windoze PC easily?
I have an RS account, I'll probably get 'em from there - Farnell seem to
charge some fantastically high prices for some of their stuff (e.g. 24-way
1.156" PCB edge connectors for ?17.00 each). Is there any mileage in
getting a gas soldering iron with an IC block (i.e. one of those things
which solders/desolders all pins in a socket at once), or will I be OK with
my regular electric iron & a vacuum desolderer?
Presumably they'd only be useful for hobbyists, and perhaps too expensive
to be mainstream. Annoyingly, about 8 years ago I could have purchased a
complete industrial PCB production line, c/w solder baths, plating line,
etc., for about ?5000. Unfortunately, not only did I not have ?5000, but I
had nowhere to put it either. I can't help but think that solder bath would
have been quite useful for removing IC sockets & the like...
Mind you, I did get the PCB drill; a micromat CNC machine. One day, I'll
put it all back together, at least I can drill my own PCBs then...
[Fireball 3040]
Righto.
That's what I was hoping you'd say :)
That figures... Maplin rarely have useful components in
stock in the
shops any more. They were out of stock of 10k resistors one time I needed
them.
They seem to have really gone downhill in the last few years; I suspect passing of Tandy has something to do with this -
why should they care,
there is no national competition. :(
I heard a rumour (nothing more) that Maplin were now (part?) owned by the
old Tandy. Which probably explains why they now sell lo-fi, etc. I am trying to work out why your soldering iron was not
on your bench
where it should have been. Unless you had taken it somewhere for a field
repair, of course.
Sad to say, I don't do anything like enough electronic
assembly/disassembly. This is only the second time I've used the iron tried it again
this morning the screen is just blank. I know the video
side
is OK, as if you let the tube warm up, then power
cycle it, you get the
garbage characters for a second or so, then it clears to blank. I've
Well, that means the CPU is running, and that it can access memory (and
that at least osme of the ROM is good). That's a step forward, surely... re-seated all
of the smaller chips to no avail; will try the big chips
tomorrow, after that it's a crash-course in microelectronic diagnosis.
I've had _many_ problems with bad IC sockets in PETs. I'd replace the lot
with turned-pin ones (I doubt Maplin still do these, if they do, they'll
never have them in stock, but RS and/or Farnell list them). [6 pin DIN plug]
Clean the pins with a contact file or (fine) wet-n-dry paper before you
start...
Makes sense...
won't
grip, and you end up melting a pin right through the plastic. Grr. I
mean, all they have to do is make the plastic bit out of bakalite -
problem
solved.
Or PTFE (which won't melt with a normal soldering iron). Or the
glass-fibre PCB material -- I managed to get some DIL headers that were
made of PCB substrate with pins inserted, and they were by far the
easiest to use of all I'd tried. They did not melt when soldered. Pity I
can't get any more... Hmm. It's
presently unidentifiable (just a black smear on the circuit
Sounds like a tantalum... Thing is, did
the tantalum cap blow because it was old, or because
something else was awry?
Most likely because it's old. It was probably a supply decoupler. I've
had the odd one on a PCB explode, and the rest remain OK. No simple
electrical problem could cause that. Have you tried the 3040 (after removing the remains of
the capacitor). It
wouldn't suprise me if it still worked!
Hmm, I'll give that a shot this afternoon I think.
Cheers Tony - all useful stuff again! And you'll make me an electronics
hobbyist yet :)
--
Cheers, Ade.
Be where it's at, B-Racing!
http://b-racing.com