28 Aug
2008
28 Aug
'08
8:29 p.m.
Hi, All,
I was recently watching "Goldfinger" and oggling the countdown timer
on the bomb. I don't think I've ever seen that type of display
technology up close, but in principle, it shouldn't be hard to
replicate.
<http://www.vintagecalculators.com/html/calculator_displays.html#Incandescent>
I was thinking that some sort of modern CNC would make short work of
the digit faces - just CAD up some outlines and bang out a few sheets.
Alternately, a pantographic sign engraver might do the trick, with
suitable templates whipped up either by hand on on a CNC.
The compact design for the type marked "KGM M4" looks intriguing as
well - a few slits cut in an aluminum back, and a simple PCB layout
for the bulbs (though I must confess I was contemplating white LEDs
rather than bulbs for a variety of reasons, including longer life
and simpler drive circuits).
As for driving it, I was thinking about something like a '145 O.C.
decimal decoder (as found in Commodore PET keyboard circuits and KIM-1
memory decoder and LED decoder circuits) per display. They aren't
particulalty expensive, and all you'd have to do is pipe in 4 bits and
let the '145 do all the work.
Nixies and other contemporary (and now faded) display technologies
are cool, but any of the glass-envelope types aren't exactly feasible
to reproduce in a home workshop.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 29-Aug-2008 at 02:50 Z
South Pole Station
PSC 468 Box 400 Temp -88.6 F (-67.0 C) Windchill -131.7 F (-90.9 C)
APO AP 96598 Wind 12.2 kts Grid 56 Barometer 657.5 mb (11489 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html
28 Aug
28 Aug
10:12 p.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
Ethan Dicks wrote:
I was recently watching "Goldfinger" and
oggling the countdown timer
on the bomb. I don't think I've ever seen that type of display
technology up close, but in principle, it shouldn't be hard to
replicate.
<http://www.vintagecalculators.com/html/calculator_displays.html#Incandescent>
I was thinking that some sort of modern CNC would make short work of
the digit faces - just CAD up some outlines and bang out a few sheets.
Alternately, a pantographic sign engraver might do the trick, with
suitable templates whipped up either by hand on on a CNC.
The compact design for the type marked "KGM M4" looks intriguing as
well - a few slits cut in an aluminum back, and a simple PCB layout
for the bulbs (though I must confess I was contemplating white LEDs
rather than bulbs for a variety of reasons, including longer life
and simpler drive circuits).
As for driving it, I was thinking about something like a '145 O.C.
decimal decoder (as found in Commodore PET keyboard circuits and KIM-1
memory decoder and LED decoder circuits) per display. They aren't
particulalty expensive, and all you'd have to do is pipe in 4 bits and
let the '145 do all the work.
Nixies and other contemporary (and now faded) display technologies
are cool, but any of the glass-envelope types aren't exactly feasible
to reproduce in a home workshop.
Ha! .. funny you should notice that (see the comment at
http://www.cs.ubc.ca/~hilpert/eec/calcs/Canon130.html). I suspect (just a
guess) that the counter in the movie is a mocked up General Radio instrument,
as they made counter instruments using their own version of that type of display.
Rick Bensene's site has some good pictures of the internals of the Canon
version (http://www.oldcalculatormuseum.com/canon161.html).
This idea was discussed on the list sometime ago, and I did a quick experiment
with some plexiglass, forming the digits with a sequence of 'dots' formed by
the end of a drill bit in the plexiglass, and white LEDs, but it was only
moderately successful. I think I was using too-thick plexiglass, and also
concluded that one would need several LEDs per digit, making it quite
expensive, but this was a couple of years ago and white LED's were pricey.
IIRC, the light dispersion of LEDs was part of the problem (that is, they don't
disperse enough compared to incandescents).
Trying to get all the LEDs arrayed around the plexiglass edges with appropriate
light shielding may become an issue. Arrays of bare LED die would be nice..
One of the nice things about using LEDs is heat dissipation wouldn't be an
issue as it was for the original designs with incandescents (note the aluminum
bulb enclosures).
A more considered effort than what I attempted may well be more successful..
10:14 p.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
On Thu, Aug 28, 2008 at 09:12:53PM -0800, Brent Hilpert wrote:
Ethan Dicks wrote:
Indeed - that's how I found that page (googling something like "goldfinger
incandescent digit").
I was recently watching "Goldfinger"
and oggling the countdown timer
on the bomb. I don't think I've ever seen that type of display
technology up close, but in principle, it shouldn't be hard to
replicate.
<http://www.vintagecalculators.com/html/calculator_displays.html#Incandescent>
Ha! .. funny you should notice that (see the comment at
http://www.cs.ubc.ca/~hilpert/eec/calcs/Canon130.html). I suspect (just a
guess) that the counter in the movie is a mocked up General Radio instrument,
as they made counter instruments using their own version of that type of display.
Could be.
Rick Bensene's site has some good pictures of the
internals of the Canon
version (http://www.oldcalculatormuseum.com/canon161.html).
Yep. Saw that, too.
This idea was discussed on the list sometime ago, and
I did a quick experiment
with some plexiglass, forming the digits with a sequence of 'dots' formed by
the end of a drill bit in the plexiglass, and white LEDs, but it was only
moderately successful. I think I was using too-thick plexiglass, and also
concluded that one would need several LEDs per digit, making it quite
expensive, but this was a couple of years ago and white LED's were pricey.
IIRC, the light dispersion of LEDs was part of the problem (that is, they don't
disperse enough compared to incandescents).
I was discussing the technology with our machinist, who was willing to mock up
a prototype digit or two if I'd give him X-Y coords (so he could dial them in
on our non-CNC milling machine), but so far, I haven't found any clear plastic
thin enough to try.
Trying to get all the LEDs arrayed around the
plexiglass edges with appropriate
light shielding may become an issue. Arrays of bare LED die would be nice..
I had thought about SMT LEDs - those should have better dispersion characteristics
than T1-3/4 packaging, I would think.
One of the nice things about using LEDs is heat
dissipation wouldn't be an
issue as it was for the original designs with incandescents (note the aluminum
bulb enclosures).
Sure - one could also use black ABS for a body - easier to work and most likely
cheaper than hunks of aluminum.
A more considered effort than what I attempted may
well be more successful..
Perhaps. Thanks for sharing your experiences.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 29-Aug-2008 at 05:10 Z
South Pole Station
PSC 468 Box 400 Temp -85.0 F (-65.0 C) Windchill -127.8 F (-88.8 C)
APO AP 96598 Wind 12.7 kts Grid 51 Barometer 658.1 mb (11465 ft)
Ethan.Dicks at usap.gov http://penguincentral.com/penguincentral.html
29 Aug
29 Aug
7:20 a.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
A more considered effort than what I attempted
may well be more successful..
Perhaps. Thanks for sharing your experiences.
10:10 a.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
This idea was discussed on the list sometime ago, and
I did a quick experiment
with some plexiglass, forming the digits with a sequence of 'dots' formed by
the end of a drill bit in the plexiglass, and white LEDs, but it was only
moderately successful. I think I was using too-thick plexiglass, and also
concluded that one would need several LEDs per digit, making it quite
expensive, but this was a couple of years ago and white LED's were pricey.
IIRC, the light dispersion of LEDs was part of the problem (that is, they don't
disperse enough compared to incandescents).
Trying to get all the LEDs arrayed around the plexiglass edges with appropriate
light shielding may become an issue. Arrays of bare LED die would be nice..
Electroluminescent wire would do for the illumination Just lay a short
piece on the edge and tape it on with silver tape.
Switching the wire off and on might be more difficult due to the
voltage and frequency (100-200V, 60 to 2000Hz.)
You could also glue a piece of high loss light pipe used for
illumination onto the edge and end light it with LEDs. This would
provide a more even illumination.
This is a technique I have been experimenting with for signage.
--
Paxton Hoag
Astoria, OR
USA
7:29 a.m.
On Thursday 28 August 2008 23:29, Ethan Dicks wrote:
Hi, All,
I was recently watching "Goldfinger" and oggling the countdown timer
on the bomb. I don't think I've ever seen that type of display
technology up close, but in principle, it shouldn't be hard to
replicate.
<http://www.vintagecalculators.com/html/calculator_displays.html#Incandesce
nt>
Interesting site. That "stylus" calculator shown on there was probably my
first computing device ever. :-)
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
10:04 a.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
----- Original Message -----
From: "Ethan Dicks" <ethan.dicks at usap.gov>
I was recently watching "Goldfinger" and oggling the countdown timer
on the bomb. I don't think I've ever seen that type of display
technology up close, but in principle, it shouldn't be hard to
replicate.
<http://www.vintagecalculators.com/html/calculator_displays.html#Incandescent>
I was thinking that some sort of modern CNC would make short work of
the digit faces - just CAD up some outlines and bang out a few sheets.
Alternately, a pantographic sign engraver might do the trick, with
suitable templates whipped up either by hand on on a CNC.
The compact design for the type marked "KGM M4" looks intriguing as
well - a few slits cut in an aluminum back, and a simple PCB layout
for the bulbs (though I must confess I was contemplating white LEDs
rather than bulbs for a variety of reasons, including longer life
and simpler drive circuits).
As for driving it, I was thinking about something like a '145 O.C.
decimal decoder (as found in Commodore PET keyboard circuits and KIM-1
memory decoder and LED decoder circuits) per display. They aren't
particulalty expensive, and all you'd have to do is pipe in 4 bits and
let the '145 do all the work.
Nixies and other contemporary (and now faded) display technologies
are cool, but any of the glass-envelope types aren't exactly feasible
to reproduce in a home workshop.
-ethan
These displays were used in a lot of equipment. I have an "Advance"
timer/counter with small versions, and a digital clock (ex-fighter control
centre) which has 8" versions.
The digits are drilled right through the Perspex, and the larger displays
have four bulbs per digit, with flat sheets of Perspex.
Jim.
10:11 a.m.
New subject: Has anyone ever tried to make 1960s-type incandescent digitaldisplays?
Jim Beacon wrote:
These displays were used in a lot of equipment. I have an "Advance"
timer/counter with small versions, and a digital clock (ex-fighter
control centre) which has 8" versions.
The digits are drilled right through the Perspex, and the larger
displays have four bulbs per digit, with flat sheets of Perspex.
Now we know why you never see Home-Made Bombs -- Nobody can get the timer.
Jim.
PS: Remember to set the timer to .001 sec slower than Bond's watch. :)
30 Aug
30 Aug
12:01 a.m.
New subject: NEC PC-8201A needs a new home...
I wanted to give the "list" first shot at this before I throw it to the dogs
on E-bay... This is a fully functional NEC PC-8201A with 32K of RAM. Also
included is the Reference Pamphlet, BASIC Reference Manual, Personal
Application Kit Guide and a User's Guide. As a bonus you also get a 300 baud
modem !! Shipping weight is about 10 pounds. The unit is in great shape and
comes from a good home ( fellow colleague at Hughes Aircraft ). If you are
interested please contact me offline and make an offer I can't refuse ( no
horse heads please ! ). Give me your Zip Code and I'll tell you how much
shipping ( Domestic USA only ) will be. I only ship UPS because ALL the
other companies have lost stuff. Thanks.
Best regards, Steven
5958
days inactive
5959
days old
8 comments
8 participants
participants (8)
-
bfranchuk＠jetnet.ab.ca -
ethan.dicks＠usap.gov -
geneb＠deltasoft.com -
hilpert＠cs.ubc.ca -
innfoclassics＠gmail.com -
jim＠g1jbg.co.uk -
rtellason＠verizon.net -
steven.alan.canning＠verizon.net