I found some 'music' wire at a local hobby shop which looks like it will
be good for replacements. Three meters of the heavy gauge and 6 of the
lighter one (that's how they sell it) was about $6.

One should do for the springs, the other for the crank, rods, stop pin
etc.

Photo of the tags:

http://groups.yahoo.com/group/friendsofdigicomp/photos/album/604383084/p\
ic/512691563/view
<http://groups.yahoo.com/group/friendsofdigicomp/photos/album/604383084/\
pic/512691563/view>

Neil




[Non-text portions of this message have been removed]

I remember getting an assortment of
   spring wire (from brookstone?) 30(?!)
years ago advertised to last a lifetime. Perfect
For smaller springs but running low on some sizes...
Want my money back!


Sent from my iPhone

On Oct 19, 2009, at 11:28 PM, "Neil" <neilsmorr@...> wrote:

> I found some 'music' wire at a local hobby shop which looks like it
> will
> be good for replacements. Three meters of the heavy gauge and 6 of the
> lighter one (that's how they sell it) was about $6.
>
> One should do for the springs, the other for the crank, rods, stop pin
> etc.
>
> Photo of the tags:
>
> http://groups.yahoo.com/group/friendsofdigicomp/photos/album/604383084/p\
> ic/512691563/view
> <http://groups.yahoo.com/group/friendsofdigicomp/photos/album/604383084/\
> pic/512691563/view>
>
> Neil
>
> [Non-text portions of this message have been removed]
>
>


[Non-text portions of this message have been removed]

Hello, everyone. I only found out about the digicomp II pretty recently, and I
must say that I am fascinated by it. So much so that I've decided I would like
to build my own.

I probably won''t be doing anything construction-wise for a month or so, until I
go on winter break from school, but at that point I'll have plenty of time to
work on it.

Here as some initial thought on how I'd like to do it:

I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks, and other
stuff like that, powered by marbles. I thought the LEGO one that first drew me
into this fascinating contraption was pretty awesome, but I don't have the
resources to use that kind of material. I have some preliminary ideas for gate
design and such, but they're not developed enough to bother detailing them here.

Also, I had the notion to put the second layer next to the first instead of
behind it, with channels for marbles connecting the two. I feel like if the
second layer was behind the first, it would be blocked and so it wouldn't be as
fun or interesting to watch. If they were placed side by side, then I would have
to employ a wire or something connecting the gates so that a flip of one also
affects the other.

I'm coming up with these ideas using the manual and the patent as guides, and I
don't imagine I'll really know how I'm going to work everything until I start
really working on it in a month or so, but I thought I'd get this out there in
case anyone has any comments or advice, or anything else to share.

Anyone?

Search the messages for "enhancements".   For communications from the
inventor of Digi-Comp II, search for "godfreyjohnt".

I've been playing with single plane ideas for some time.  Contact me
directly if you want: PasoDad at aol.com.

-Bob S.


-----Original Message-----

I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks, and
other stuff like that, powered by marbles.

Also, I had the notion to put the second layer next to the first instead of
behind it, with channels for marbles connecting the two.

I thought I'd get this out there in case anyone has any comments or advice,
or anything else to share.

Anyone?

sq_ocelot wrote:

> I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks,
> and other stuff like that, powered by marbles. I thought the LEGO
> one that first drew me into this fascinating contraption was pretty
> awesome, but I don't have the resources to use that kind of material.

I understand - the LEGO one took a lot of materials, and is big and bulky, and
limiting myself to "pure LEGO" made it very difficult to reliably flip gates
(the soccer balls are very light). However, it's a great way to prototype.

Ideally I want to make a DCII & Dr Nim out of wood: take a thick board and a
router to do all the channels, with small pins pivoting the gates. The gates
themselves could be made out of wood as well, but I'd probably go with plastic
(clear lucite or acrylic would look good, and you could color them to suit, or
have them cover and obscure numbers written under them). The denser the balls,
the easier it is to get them to throw gates, so I'd use marbles, or even ball
bearings... but every time you change the size or weight, you'll change the way
the gates act as well, so expect some tuning.

As to a quicker cheaper way (the LEGO one was about $700 if I remember), you
might use pegboard, allowing you to adjust supports for the ramps and guides, as
well as a mounting place for the gates. It will be *big*... but start small.
When I built it out of LEGO, I did it as a series of repeated units (almost all
the accumulator registers are identical, for instance), so I built a couple and
cascaded them, adjusting until it was working well, and then stretched it to the
entire thing. I'd suggest something fairly stiff for the backing... probably not
cardboard, unless it's supported by wood or similar behind. Popcicle or kraft
sticks sound like a possibility for guides, or even disposable drinking straws
for a 1st attempt... it the gates that are a bigger issue I suspect. For a long
calculation, DCII has to throw a *lot* of gates... and if even one flips wrong,
the result is garbage.

> I have some preliminary ideas for gate design and such, but they're
> not developed enough to bother detailing them here.

I'd still love to hear them.

> Also, I had the notion to put the second layer next to the first
> instead of behind it, with channels for marbles connecting the
> two.

I agree it would be neater if you could see that. I actually tried what you
mention for the LEGO version, but the friction of moving two gates on two pivots
with a bit of string between them was much too great... but I was limited to
those light balls. With heavier balls, this might be doable, but I've not
figured out the design this way as yet. BTW, on the LEGO version the toughest
thing to get correct was the ball release, which is the only place I used string
to activate something. It's slightly tricky to get a ball to reliably release
another of the same mass.

> I'm coming up with these ideas using the manual and the patent as
> guides, and I don't imagine I'll really know how I'm going to work
> everything until I start really working on it in a month or so...

Someone here (Bob?) had some photographs of the bottom layer that proved
critical - while I could see how it was supposed to work, sort of, from the
patent, the picture really helped.

And any further discussion you want to have on this, you can certainly contact
me off-group as well (brdavis@...), but I'd really appreciate it if you did
as much as possible "out in the open" on the group, so the rest of us can live
(& learn!) vicariously :).

--
Brian Davis

In my mind, the DigiComp I is the only "true" mechanical computer. I bought one
of the new $65 cardboard ones a couple years ago and assembled it, but it
doesn't work nearly as smoothly as the original plastic ones (I had one back in
the late 60's, and I still kick myself for giving it away to a friend).

I have been thinking of using my cardboard DigiComp as a template to make a
DigiComp IV. It would work just like the DigiComp I, except I would add an extra
row and column to the matrix so it would have a 4-bit memory, allowing it to
count up to 15 instead of just 7. Could the Harvard Mark I be far behind?

I think the best material for this kind of project is plexiglass. If you have a
router table you can easily trim the plastic to any shape you want, and it looks
really nice too.

Kurt Kammeyer

--- On Fri, 11/13/09, bdavis61856 <brdavis@...> wrote:

From: bdavis61856 <brdavis@...>
Subject: [Friends of DigiComp] Re: I'm new - I want to build me a DC2
To: friendsofdigicomp@yahoogroups.com
Date: Friday, November 13, 2009, 1:49 PM







 









       sq_ocelot wrote:



> I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks,

> and other stuff like that, powered by marbles. I thought the LEGO

> one that first drew me into this fascinating contraption was pretty

> awesome, but I don't have the resources to use that kind of material.



I understand - the LEGO one took a lot of materials, and is big and bulky, and
limiting myself to "pure LEGO" made it very difficult to reliably flip gates
(the soccer balls are very light). However, it's a great way to prototype.



Ideally I want to make a DCII & Dr Nim out of wood: take a thick board and a
router to do all the channels, with small pins pivoting the gates. The gates
themselves could be made out of wood as well, but I'd probably go with plastic
(clear lucite or acrylic would look good, and you could color them to suit, or
have them cover and obscure numbers written under them). The denser the balls,
the easier it is to get them to throw gates, so I'd use marbles, or even ball
bearings... but every time you change the size or weight, you'll change the way
the gates act as well, so expect some tuning.



As to a quicker cheaper way (the LEGO one was about $700 if I remember), you
might use pegboard, allowing you to adjust supports for the ramps and guides, as
well as a mounting place for the gates. It will be *big*... but start small.
When I built it out of LEGO, I did it as a series of repeated units (almost all
the accumulator registers are identical, for instance), so I built a couple and
cascaded them, adjusting until it was working well, and then stretched it to the
entire thing. I'd suggest something fairly stiff for the backing... probably not
cardboard, unless it's supported by wood or similar behind. Popcicle or kraft
sticks sound like a possibility for guides, or even disposable drinking straws
for a 1st attempt... it the gates that are a bigger issue I suspect. For a long
calculation, DCII has to throw a *lot* of gates... and if even one flips wrong,
the result is garbage.



> I have some preliminary ideas for gate design and such, but they're

> not developed enough to bother detailing them here.



I'd still love to hear them.



> Also, I had the notion to put the second layer next to the first

> instead of behind it, with channels for marbles connecting the

> two.



I agree it would be neater if you could see that. I actually tried what you
mention for the LEGO version, but the friction of moving two gates on two pivots
with a bit of string between them was much too great... but I was limited to
those light balls. With heavier balls, this might be doable, but I've not
figured out the design this way as yet. BTW, on the LEGO version the toughest
thing to get correct was the ball release, which is the only place I used string
to activate something. It's slightly tricky to get a ball to reliably release
another of the same mass.



> I'm coming up with these ideas using the manual and the patent as

> guides, and I don't imagine I'll really know how I'm going to work

> everything until I start really working on it in a month or so...



Someone here (Bob?) had some photographs of the bottom layer that proved
critical - while I could see how it was supposed to work, sort of, from the
patent, the picture really helped.



And any further discussion you want to have on this, you can certainly contact
me off-group as well (brdavis@iusb. edu), but I'd really appreciate it if you
did as much as possible "out in the open" on the group, so the rest of us can
live (& learn!) vicariously :).



--

Brian Davis

























[Non-text portions of this message have been removed]

In my mind, the DigiComp I is the only "true" mechanical computer. I
bought one of the new $65 cardboard ones a couple years ago and
assembled it, but it doesn't work nearly as smoothly as the original
plastic ones (I had one back in the late 60's, and I still kick myself
for giving it away to a friend).

I
have been thinking of using my cardboard DigiComp as a template to make
a DigiComp IV. It would work just like the DigiComp I, except I would
add an extra row and column to the matrix so it would have a 4-bit
memory, allowing it to count up to 15 instead of just 7. Could the Harvard Mark
I be far behind?

I
think the best material for this kind of project is plexiglass. If you
have a router table you can easily trim the plastic to any shape you
want, and it looks really nice too.

Kurt Kammeyer

--- On Fri, 11/13/09, sq_ocelot <no_reply@yahoogroups.com> wrote:

From: sq_ocelot <no_reply@yahoogroups.com>
Subject: [Friends of DigiComp] I'm new - I want to build me a DC2
To: friendsofdigicomp@yahoogroups.com
Date: Friday, November 13, 2009, 2:33 AM







 









       Hello, everyone. I only found out about the digicomp II pretty recently,
and I must say that I am fascinated by it. So much so that I've decided I would
like to build my own.



I probably won''t be doing anything construction- wise for a month or so, until
I go on winter break from school, but at that point I'll have plenty of time to
work on it.



Here as some initial thought on how I'd like to do it:



I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks, and other
stuff like that, powered by marbles. I thought the LEGO one that first drew me
into this fascinating contraption was pretty awesome, but I don't have the
resources to use that kind of material. I have some preliminary ideas for gate
design and such, but they're not developed enough to bother detailing them here.



Also, I had the notion to put the second layer next to the first instead of
behind it, with channels for marbles connecting the two. I feel like if the
second layer was behind the first, it would be blocked and so it wouldn't be as
fun or interesting to watch. If they were placed side by side, then I would have
to employ a wire or something connecting the gates so that a flip of one also
affects the other.



I'm coming up with these ideas using the manual and the patent as guides, and I
don't imagine I'll really know how I'm going to work everything until I start
really working on it in a month or so, but I thought I'd get this out there in
case anyone has any comments or advice, or anything else to share.



Anyone?

























[Non-text portions of this message have been removed]

>  In my mind, the DigiComp I is the only "true" mechanical computer.

Whoa there pardner!

Leaving out Babbage's Engines, Zuse's Z1, adding machines, old gas pumps and all
mechanical analog computers; I suppose you're only comparing DC1 to DC2. 
Neither actually qualifies as a computer but the DC2 has greater similarity.  It
even includes a programming language (DIGITRAN).

That said, I think the DC1 was the more interesting machine.  Too bad it wasn't
represented as what it truly was -- a Programmable Logic Device (PLD).

-Bob S.

--- In friendsofdigicomp@yahoogroups.com, "bdavis61856" <brdavis@...> wrote:
>
> sq_ocelot wrote:
>
> > I'm thinking I'll do it out of cardboard, popsicle sticks, toothpicks,
> > and other stuff like that, powered by marbles.

>I'd suggest something fairly stiff for the backing... probably not cardboard,
unless it's supported by wood or similar behind. Popcicle or kraft sticks sound
like a possibility for guides, or even disposable drinking straws for a 1st
attempt... it the gates that are a bigger issue I suspect. For a long
calculation, DCII has to throw a *lot* of gates... and if even one flips wrong,
the result is garbage.
>

Well, I'm a college student without a whole lot of funds to work with, and I'm
trying to do this on as small a budget as possible, so I'm gonna go ahead and
use cardboard from around my house (probably to be reinforced with wooden
skewers or something like that) and not out of wood that I'd have to go buy.
I've actually started some construction (just basic surface and guides stuff; I
was too excited to wait!), and I'll talk about that below.

> > I have some preliminary ideas for gate design and such, but they're
> > not developed enough to bother detailing them here.
>
> I'd still love to hear them.

Well, I've done some more considering since last night, and what I figured is
I'd take three short pieces cut from a popsicle stick and arrange them in an
upside-down Y shape for the flip-flops, reinforcing them from the front with
other pieces of stick glued on (this would serve both to help the Y retain its
shape and to keep balls from falling out the front -- though I have no idea if
the latter is going to be an issue). Right between the 'legs' of the Y, I would
glue a wooden skewer (cut to an appropriate length), which would be stuck
through the cardboard and serve as the pivot for the gate.

Other gates would be similar, but shaped differently depending on what kind it
is (like, just a line, or a checkmark-shape for the half flip-flops, etc.)

>
> > Also, I had the notion to put the second layer next to the first
> > instead of behind it, with channels for marbles connecting the
> > two.
>

So, the basic structure for the design that I'm thinking about involves one
large sheet of cardboard to serve as the back of the entire structure, with two
raised panels, one being the top layer of the original, the other being the
lower layer. The two panels would be side-by-side, with a few inches gap
between. Where the holes in the front appear, there would be two wooden skewers
close enough to carry the marble right behind the hole, but angled outwards so
that the marble drops through them onto a rail (which I'm thinking would just be
another wooden skewer set away from the back piece of cardboard a bit, so that
the marble would roll between the skewer and the back wall), then the marble
would roll out onto the second layer via a similar (but reversed) mechanism
(which I haven't thought entirely through yet, I don't know where I'll have to
throw up walls so that the marble doesn't fall out or anything, but I'll see how
it goes when I construct that part), then once it does it's stuff, it would go
back to the original panel by way of the same kind of thing.

About the gate design (which I explained above), I would stick the skewer
through both layers of cardboard to keep it from going out of line. Then, I
thought that to make a movement in a switch on the second layer transfer to the
first (and vice versa) where it's supposed to, I could put a gear or a wheel on
those skewers and connect them with a loop of string or elastic, so that one
turns the other (if I glue the string in a single dot on the 'outside' part of
each wheel, would that make the wheels guaranteed to turn each other? I feel
like it would, but I'm not entirely sure).

Like I said, I've begun some preliminary construction, which simple included
finding a good piece of cardboard for the top-level panel, and tracing all the
guides from the figure in the manual onto it, and hot-gluing (which I've decided
will be my primary binding agent, it works surprisingly well, better even than I
thought it would) some popsicle sticks onto those lines that I'm sure are
correct and don't need messing with to make them work. Is that a good idea, to
just copy the design of that figure from the manual onto the cardboard, or will
it turn out to be problematic? I feel like it should be fine, but then again I'm
a total novice at all of this and I have very little clue.

I've got a question, though, about the holes in the front panel, though: how
many are there, and where are they? The patent shows, I believe, six (excluding
the return ramp), one behind each of the four M registers, and then two at the
top (whose purpose I don't entirely understand, could someone explain please?).
The figure from the manual doesn't show any, but I'm guessing that the four
behind the Ms are still there just obscured, but I can't see where those two
higher holes are supposed to be. Then, in the pictures on this group of the
wooden DC2, I see six holes again, but only one where the two pictured on the
patent are supposed to be, and another one that is somewhere directly above the
four for the Ms. I'm a little confused, so if someone could explain all this
that would be great.

> Someone here (Bob?) had some photographs of the bottom layer
> that proved critical - while I could see how it was supposed to
> work, sort of, from the patent, the picture really helped.

OK -- Pictures of the boards with most parts removed are now in the
Digi-Comp II folder of the group's pictures.  There is also a folder for a
wooden DCII showing back details.

-Bob S.

Friction of wood to cardboard may be a problem.  If you glue the gate to the
shaft, the shaft will rotate through two layers of cardboard.  If you link
two gates the friction doubles.

The original machine was nearly as compact as the gates would allow.  The
metal shafts had little friction against the plastic bushings so little
torque was needed for rotation.  Your gates may need to have longer arms or
use steel marbles (or both).

When linking reset gates to flip-flops, string will work because the action
only goes one direction.  You'll need rigid links or pairs of string links
for an inverter function between gates.

IF you have the layers side to side, there is no need for marbles to cross
side to side.  Most of the time a marble goes into a hole it is just to exit
without hitting gates on the way down.

Search for the enhancements suggested for inverting the accumulator.

Consider spending about $5 for a half or quarter sheet of 1/4" or thicker
Masonite.  If you don't use the hidden layers you don't need the shaft to
rotate with the flip-flop.  Use wire nails (brads?) and you have wood to
metal bearing surfaces, you don't need an extra layer to stabilize the
shafts, and your finished machine may last longer.  Rent time on a drill
press (mooch from a friend) to get the pilot holes perpendicular to the
surface.  Test ideas one element or group at a time on scrap.

My first marble adder used toothpicks and a shoebox.  My second marble adder
used wire shafts (paperclips), sheet metal gates (food cans) soldered to the
shafts, and layers of Plexiglas to separate layers.

-Bob S.

Thanks. Those board pictures help quite a bit in terms of getting my brain to
picture how it all goes.

--- In friendsofdigicomp@yahoogroups.com, "Bob S." <pasodad@...> wrote:
>
> > Someone here (Bob?) had some photographs of the bottom layer
> > that proved critical - while I could see how it was supposed to
> > work, sort of, from the patent, the picture really helped.
>
> OK -- Pictures of the boards with most parts removed are now in the
> Digi-Comp II folder of the group's pictures.  There is also a folder for a
> wooden DCII showing back details.
>
> -Bob S.
>

Try to add Teflon tape to rubbing parts.

Neil



From: Bob S.

Friction of wood to cardboard may be a problem. If you glue the gate to the
shaft, the shaft will rotate through two layers of cardboard. If you link
two gates the friction doubles.



[Non-text portions of this message have been removed]

"Bob S." <pasodad@...> wrote:

>>  In my mind, the DigiComp I is the only "true" mechanical computer.
>
> Whoa there pardner!
>
> Leaving out Babbage's Engines, Zuse's Z1, adding machines, old gas
> pumps and all mechanical analog computers; I suppose you're only
> comparing DC1 to DC2.  Neither actually qualifies as a computer but
> the DC2 has greater similarity.

I'd have to agree - neither is as yet a computer, but I can see ways of getting
DC2 there a lot clearer than DC1 (and if I ever find the time, I'll try to move
that way: it needs an addressable memory and a few very simple instructions with
a decoder). There are a *lot* of amazing mechanical & analog computers; the
Deutschs Museum in Munich actually has a section of a floor dedicated to such
machines, I just wish I would have had enough time to really look through it
when I was there this summer (I suspect a couple days might have been sufficient
:) ).

Zuse's Z1 is one of the most inspired mechanical examples I've ever seen (on the
web)... and I'd never even heard of it until this group.

--
Brian Davis

--- In friendsofdigicomp@yahoogroups.com, "Neil Morrison" <neilsmorr@...> wrote:
>
> Try to add Teflon tape to rubbing parts.
>
> Neil
>
>
>
> From: Bob S.
>
> Friction of wood to cardboard may be a problem. If you glue the gate to the
> shaft, the shaft will rotate through two layers of cardboard. If you link
> two gates the friction doubles.
>
>
>
> [Non-text portions of this message have been removed]
>


Well I did some tests with this thing, and I found that if I poked a hole in the
cardboard with a skewer, and then took the skewer out and made the hole just a
tiny big bigger with an x-acto knife, the skewer could spin quite freely in it
(I tested it through two layers, too, and it still worked great). So, I think
that's what I'm gonna do.

Also, I understand more about how the two-layered thing works, and I feel like
my initial plan to put them side by side would be far more trouble than it would
be worth. So, I still think I'm going to do it like the real thing, and put the
second layer behind the first. I would still like some explanation of what the
two highest holes on the board do, though, if someone would please enlighten me.

And about all the crazy materials that are being suggested to me, thanks
everyone, but I'm only doing this for fun. I know it may not last forever, or
parts of it may work less than perfectly, but I'm okay with that. I'm going to
use my cheap materials and methods, and I'm sure the result will still work just
fine. Or at least, well enough for me. Maybe one day I'll make a better one. But
I do appreciate the advice, and if any of you have more to add, then by all
means let me know. Thanks.

--Andrew G.

> I would still like some explanation of what the two highest holes > on the
board do, though, if someone would please enlighten me.

Looking at photo of top board, highest hole is at the "CLEAR" switch.  When
the switch is "on", a marble drops through the hole to the lower level where
it is guided to "half flip-flops" attached to each of the accumulator
flip-flops to reset them all to zeros.

Next hole is at CF-1 (complement flip-flop).  When a marble drops through
this hole to the lower level it is guided to flip-flops attached to each of
the mode switches to toggle them between all left or all right.  See page 33
of the instruction manual for a description of the one's and two's
complement operation.

Best advice:  Download and run the DigiComp II Emulator from our group's
files section.  You won't see the marble when it's on the lower level but
you will see how it affects the top level.

-Bob S.

> Also, I understand more about how the two-layered thing works

If you're using two layers of corrugated cardboard, make sure one layer
is 90 degrees to the other. Like plywood, it'll make it much stronger.

Thanks. And yeah, I tried to download the emulator, but it wouldn't work for
some reason.

hello Andrew,
I built the wooden DC2 on the fotos.You can try other material but wood,for me
its was the most easiest and cheapest way .Friction was only particulary a
problem,I worked with washers for distance and friction.
A little difficulty were the dynamic effects of the balls and the gates, i had
particulary to implement break elements. And it had been essential to adjust
every path and dividor of the balls.
The emulator is very helpful for understanding the DC2!
Good luck for your work,
yours Martin from Stuttgart Germany




________________________________
From: sq_ocelot <no_reply@yahoogroups.com>
To: friendsofdigicomp@yahoogroups.com
Sent: Sun, November 15, 2009 2:06:21 PM
Subject: Re: [Friends of DigiComp] I want to build me a DC2


Thanks. And yeah, I tried to download the emulator, but it wouldn't work for
some reason.



------------------------------------

Yahoo! Groups Links






[Non-text portions of this message have been removed]

You're right - I should have specified "within the Digicomp line"

Kurt

--- On Sat, 11/14/09, Bob S. <pasodad@...> wrote:

From: Bob S. <pasodad@...>
Subject: RE: [Friends of DigiComp] I'm new - I want to build me a DC2
To: friendsofdigicomp@yahoogroups.com
Date: Saturday, November 14, 2009, 2:36 AM







 









       >  In my mind, the DigiComp I is the only "true" mechanical computer.



Whoa there pardner!



Leaving out Babbage's Engines, Zuse's Z1, adding machines, old gas pumps and all
mechanical analog computers; I suppose you're only comparing DC1 to DC2. 
Neither actually qualifies as a computer but the DC2 has greater similarity.  It
even includes a programming language (DIGITRAN).



That said, I think the DC1 was the more interesting machine.  Too bad it wasn't
represented as what it truly was -- a Programmable Logic Device (PLD).



-Bob S.

























[Non-text portions of this message have been removed]

I should have clarified - "The only true DigiComp computer". The DC1 is really a
brilliant design. I'm thinking of building a DigiComp IV by increasing the width
and height of the matrix to 4x4, so it can count up to 15 instead of just 7.

Kurt

--- On Sun, 11/15/09, bdavis61856 <brdavis@...> wrote:

From: bdavis61856 <brdavis@...>
Subject: Re: [Friends of DigiComp] I'm new - I want to build me a DC2
To: friendsofdigicomp@yahoogroups.com
Date: Sunday, November 15, 2009, 1:59 AM







 









       "Bob S." <pasodad@... > wrote:



>>  In my mind, the DigiComp I is the only "true" mechanical computer.

>

> Whoa there pardner!

>

> Leaving out Babbage's Engines, Zuse's Z1, adding machines, old gas

> pumps and all mechanical analog computers; I suppose you're only

> comparing DC1 to DC2.  Neither actually qualifies as a computer but

> the DC2 has greater similarity.



I'd have to agree - neither is as yet a computer, but I can see ways of getting
DC2 there a lot clearer than DC1 (and if I ever find the time, I'll try to move
that way: it needs an addressable memory and a few very simple instructions with
a decoder). There are a *lot* of amazing mechanical & analog computers; the
Deutschs Museum in Munich actually has a section of a floor dedicated to such
machines, I just wish I would have had enough time to really look through it
when I was there this summer (I suspect a couple days might have been sufficient
:) ).



Zuse's Z1 is one of the most inspired mechanical examples I've ever seen (on the
web)... and I'd never even heard of it until this group.



--

Brian Davis

























[Non-text portions of this message have been removed]

Eric Uhrhane designed a computer to use elements similar to those in DCII.  He
wrote his own simulator (no animation) and has much of the simulation done.

This is an ambitious project with 30 instructions and a hardware multiplier. 
This is a spare time project for a very busy fellow.  It started in 2005 and the
most recent entry was May 2009.

http://ballcomputer.blogspot.com/

We exchanged a couple of emails but I guess I scared him off.

-Bob S.

I have a Digi-Comp 1 with original box and manuals that I am reluctantly parting
with.  Does anyone have an idea of how much these are worth?  It's in very good
condition.  Also, if I sell on eBay, what category would be best to use,
something in toys or computers?  Thanks in advance for any help.

Hi. I'll buy it. I've been looking for one. Please get back with me!
Thanks, Jim.


[Non-text portions of this message have been removed]

This will get somewhere between $50 and $150, depending on how well it
displays in pictures.  They aren't bringing the same money they were 2-3
years ago- sign of the economic times. Probably best to put in Toys &
Hobbies->Educational on eBay, but it doesn't matter a whole lot.  Those who
are wanting one will find it, no matter where you put it.



   _____

From: friendsofdigicomp@yahoogroups.com
[mailto:friendsofdigicomp@yahoogroups.com] On Behalf Of hexapodist
Sent: Monday, November 16, 2009 11:36 PM
To: friendsofdigicomp@yahoogroups.com
Subject: [Friends of DigiComp] Digi-Comp 1 For Sale




I have a Digi-Comp 1 with original box and manuals that I am reluctantly
parting with. Does anyone have an idea of how much these are worth? It's in
very good condition. Also, if I sell on eBay, what category would be best to
use, something in toys or computers? Thanks in advance for any help.







[Non-text portions of this message have been removed]

I'll take it! Thanks, Jim.


[Non-text portions of this message have been removed]

Hi,

How much are you asking?  I'm interested.

Tom McCaffrey

--- On Tue, 11/17/09, hexapodist <hexapodist@...> wrote:

From: hexapodist <hexapodist@...>
Subject: [Friends of DigiComp] Digi-Comp 1 For Sale
To: friendsofdigicomp@yahoogroups.com
Date: Tuesday, November 17, 2009, 1:36 AM







 









       I have a Digi-Comp 1 with original box and manuals that I am reluctantly
parting with.  Does anyone have an idea of how much these are worth?  It's in
very good condition.  Also, if I sell on eBay, what category would be best to
use, something in toys or computers?  Thanks in advance for any help.

























[Non-text portions of this message have been removed]

Does anyone know where I might purchase the real deal. The Digi-Comp made
from plastic parts? Thanks, Jim.

--- In friendsofdigicomp@yahoogroups.com, "jell4912" <rawhide169@...> wrote:
>
>    Does anyone know where I might purchase the real deal. The Digi-Comp made
from plastic parts? Thanks, Jim.
>

eBay.

Scott

They are frequently found on e-Bay... I just got another one for $20.  Missing a
few pieces, but with the couple I have bought, I can build one complete working
model... I'm still missing an "or" gate, but I have everything else.

  Dr. Smith, ThD




________________________________
From: jell4912 <rawhide169@...>
To: friendsofdigicomp@yahoogroups.com
Sent: Fri, November 27, 2009 6:13:17 AM
Subject: [Friends of DigiComp] Digi-Comp I


Does anyone know where I might purchase the real deal. The Digi-Comp made from
plastic parts? Thanks, Jim.







[Non-text portions of this message have been removed]