Introduction - Building a replica

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Hi Everyone!

Just wanted to drop in and say hi, and give you a short introduction.

This year for Christmas I gave myself a Newton board and a parts kit from Unicorn. I've been busy reading all the forum postings, still in progress, to educate my self before I start. I was also fortunate enough to meet Cory over on the Vintage Computer forum. After reading many messages here I see that I am in good hands.

Today I downloaded and started playing with POM to get a feel for the WOZ monitor. Even playing with the POM I get chills up my spine in anticipation of the "real" thing.

My experience goes back to the mid 1970's where I designed and built my first microcomputer based on the Intel 8008. (You may have guessed that from my user id...) Back then I spent 3 years designing, building, and wire wrapping my system. Some of you may have seen my sites where I refer to the experience.

8008chron

I also have a link on there to my chronworks site. Last year I built a single board Z80 CPM machine. I've also been working on restoring a DEC PDP11/83.

I look forward to hanging out with all of you!

len

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speedyG's picture
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Joined: Nov 16 2011
Posts: 2413
Re: Introduction - Building a replica

Hello 8008guy,

first of all welcome to the community,
second we wish you much pleasure while assembling the Newton. Which one did you purchase ?
The Newton NTI or the Newton One ?
The reason is that the one is a replication of the so called "pre NTI" Apple 1 and the other is replication
of the "NTI version" of the Apple 1. You might detect the differences of the 2 versions while viewing the
related pages at:
http://www.appleii-box.de/
There are several detail pictures of the different kinds of assembly, that you might think about
before starting to heat up the soldering iron - even if you remain in general with the parts kit from Unicorn.....

sincerely speedyG

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the second part includes less friends but a lot more joy on life....

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Joined: Jan 1 2015
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Re: Introduction - Building a replica

Hi SpeedyG,

Mine is the Newton-1 board without the logo on the front. My parts kit does have the smaller blue electrolytic caps to match. Although I don't have the TI sockets, mine are the machine frame. Corey suggests using machine sockets, as the TI sockets are of poor quality.

My intention is to build a good replica that will function for years, I don't need an exact copy. Keeping it visually perfect is secondary. Being a complete Apple 1 novice I'm just beginning to learn the subtle differences.

It's ironic how we love to revisit our pasts. Another of my many passions involve a replica of a 1965 Shelby Cobra. Just like an Apple 1, the originals are nearly untouchable with just over 1000 being built. Interestingly enough my "Cobra" was built by the same manufacturer who is building the current production Shelby's, bummer we can't do that with the Apple one. The big difference between the Cobra and the Apple 1 replicas is that under the skin the Cobras are built with newly manufactured parts. (Bummer they don't make 2504's and 2519 today...) I suppose that when you are moving at 150 mph you care more that the car is going to hold together than looking perfectly original. Smile Close is good enough!

Any suggestions before I start will be truly appreciated.

Cheers len

speedyG's picture
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Joined: Nov 16 2011
Posts: 2413
Re: Introduction - Building a replica

Hello 8008guy,
like in real life there are two groups reölated to the replica´s ....
those who want to keep as close as possible to the original, like mer and corey....
and those who rather prefer to get a close but more sure working bit of technic....
i just wanted to spot out the differences .... instead of making suggestions just
spotting out availiable ( or more difficult ) options..... it´s rather better to know
about options and availiable choices before staring with a project istead of getting
information later after project started halfway and resulting to problems in switching the rail....
as mentioned here in several threads the kit set from Unicorn is a quite good option
for those who rather more prefer to get a good and reliable piece of working technic ....
so just enjoy the project and i wish you good luck with both projects
the apple 1 replica and the Shelbey..... i was always as kid a fan of the Shelbey without
any chance to get in touch of such a great car.... i had a set of cards and while playing
that game the Shelbey always got most of the cards by speed.... like the Facel Vega with
horsepower.... nowadays there are quite a bunch of cars that would hijack the Facel Vega
by horsepower.... ( gosh !.... up to 1099 horses under the hood... who can tame such a
stampede of mustangs ? )
LOL
speedyG

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the second part includes less friends but a lot more joy on life....

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Posts: 47
Re: Introduction - Building a replica

Hi SpeedyG,

Thank you your comments. It does truly help to know what compromises I am facing. When I start a project I try and gather as much information as I can before I start the process of buying the parts. I've been wanting to build an Apple 1 for a long time. It's a bummer that I didn't buy the chips a long time ago when they were more available, especially the ceramic parts. Fifteen years ago I emailed WOZ about trying to get a PCB layout. As some people know here, WOZ will actually respond! He did to me and told me that nothing was available. So I stuck the schematics on the shelf. It wasn't until recently that I discovered that I could get parts and a board, so I jumped! When I bought the Newton board I had no idea of the Mimeo board. I'm not sure if I knew of both which one I would have chosen in the end anyway... Although I am really impressed with Mike's work and may have gone that route because he is more local.

The Unicorn kit is complete enough that things should go together reasonably well. An "if" someday I should come across a ceramic CPU or PIA I can swap them out.

One thing tho, the bypass caps that came with my Unicorn kit were 1uf, not .1uf as expected. Has anyone else used the 1uf caps in their build?

Oh ye... I finished the Cobra in 2007. I have a LOT of miles and smiles from that. 2000lbs and 700hp. The experience has been TOTALLY authentic for me. Smile

If you care to look... KobraBytes

speedyG's picture
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Re: Introduction - Building a replica

Hello 8008guy,

i wonder about the filtercaps.... they realy should be 0,1 µF = 100 nF !
It seems someone made a mistake at Unicorn....
The Unicorn set should be according to the list given by Mike Willegal.
He is member here so i recommend to ask him if he altered for any reason the list at Unicorn...
http://www.applefritter.com/user/24359

My versions at least all are equipped with 100nF according to the availiable pictures taken
from original boards and the List from Mike...:

And the Shelby ... ? Wow ! What a beauty ! there is here a thread related to cars from the 70´s:
http://www.applefritter.com/content/70s-cars
It´s really worth if you add there the link to your page and the pictures taken....
i love the pictures in the gallery showing the assembly of the cars ... very impresive !

sincerely speedyG

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In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

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Posts: 20
Re: Introduction - Building a replica

Unicorn has been shipping 1.0 uf caps for some time with the kits. I purchased mine in July and they shipped 1.0 uf caps. This is what is specified on the board silkscreen and in the documentation, but apparently the actual Apple 1s were built with 0.1 uf caps.

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Re: Introduction - Building a replica

Whitexkr,

So did you use the 1uf caps? Or buy .1uf caps in your build?

len

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Re: Introduction - Building a replica

Thanks SpeedyG,

I'll ping Mike as well. Tomorrow I'll look at the 70's cars. Smile

len

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Re: Introduction - Building a replica

I ended up using the 1 uf caps, but I will not rule out changing them if I come across the correct parts.

However, I definitely did not use the large bright yellow .001 uf ceramics if Unicorn is still shipping those. Appearance-wise those are not even remotely close to the correct part.

I built the Unicorn kit to get the Mimeo up and running, and little by little I am upgrading to the original parts and date codes as I can locate (and afford in the case of the white ceramic 6502) them.

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Posts: 382
Re: Introduction - Building a replica

My BOM had listed 1.0 UF caps as actually .1UF, but Rob (Unicorn) ships 1.0UF. I mentioned this to Rob a while back, but I guess he didn't bother changing. Rob is not the kind of guy to be concerned about exact date codes and part number, as long as it works. If you are date code kind of guy, you might be better off finding your own parts or supplimenting Rob's parts kit with your own finds.

Anyway because of all the noise on the supply rails, 1.0 UF might be a better solution, though not exactly accurate. There are two other mistakes in my BOM. One the mixer resistors in the Video output is actually populated with 1.2 K ohm instead of 1.5K ohm and the 7450 in the video circuit is actually a 7451 on original boards. Oh, and the heat sink is only 1 inch high, not 1.25.

Also, if you look at images closely, the 330 ohm is not an ordinary Omite carbon composition resistor.

Regards,
Mike W.

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Re: Introduction - Building a replica

Thanks Mike,

I'll note those differences and verify everything.

Len

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Re: Introduction - Building a replica

whitexkr wrote:

However, I definitely did not use the large bright yellow .001 uf ceramics if Unicorn is still shipping those. Appearance-wise those are not even remotely close to the correct part.

I did not use the bright yellow parts on my Mimeo either. I purchased ceramic versions that were at least similar in size and color to the orignals. While they aren't an exact replacement, they look much better.

I also selected parts from the package I purchased on eBay that measured higher values based on Mike's recommendations for the .1uf versions.

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Re: Introduction - Building a replica

I have a good supply of old ceramics that I can do the same with my RCL meter.

ChristopherB wrote:
whitexkr wrote:

However, I definitely did not use the large bright yellow .001 uf ceramics if Unicorn is still shipping those. Appearance-wise those are not even remotely close to the correct part.

I did not use the bright yellow parts on my Mimeo either. I purchased ceramic versions that were at least similar in size and color to the orignals. While they aren't an exact replacement, they look much better.

I also selected parts from the package I purchased on eBay that measured higher values based on Mike's recommendations for the .1uf versions.

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Re: Introduction - Building a replica

Can anyone point me to some hi-res pictures of the non-nti original? I only have a hi-res of the nti and the 330 ohm appears to be a carbon comp. I can see the 1.2k in the output ok, and the 7450.

Can anyone suggest a supplier for the carbon comps?

len

Mike WIllegal wrote:

My BOM had listed 1.0 UF caps as actually .1UF, but Rob (Unicorn) ships 1.0UF. I mentioned this to Rob a while back, but I guess he didn't bother changing. Rob is not the kind of guy to be concerned about exact date codes and part number, as long as it works. If you are date code kind of guy, you might be better off finding your own parts or supplimenting Rob's parts kit with your own finds.

Anyway because of all the noise on the supply rails, 1.0 UF might be a better solution, though not exactly accurate. There are two other mistakes in my BOM. One the mixer resistors in the Video output is actually populated with 1.2 K ohm instead of 1.5K ohm and the 7450 in the video circuit is actually a 7451 on original boards. Oh, and the heat sink is only 1 inch high, not 1.25.

Also, if you look at images closely, the 330 ohm is not an ordinary Omite carbon composition resistor.

Regards,
Mike W.

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Posts: 382
Re: Introduction - Building a replica

I have better images on a server at home, but there are some images on my registry page in which you can tell that the 330 is unique on some boards. Here is one.

http://www.willegal.net/appleii/images/a1registry/Larson2lg.jpg

regards,
Mike Willegal

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Posts: 47
Re: Introduction - Building a replica

Hi Mike,

Thanks for the picture.

So was that just some boards? Or all of the first run?

len

Mike WIllegal wrote:

I have better images on a server at home, but there are some images on my registry page in which you can tell that the 330 is unique on some boards. Here is one.

http://www.willegal.net/appleii/images/a1registry/Larson2lg.jpg

regards,
Mike Willegal

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Posts: 382
Re: Introduction - Building a replica

Before everyone goes out and buys 1" high heat sinks, I think someone with current access to an original Apple 1, should recheck the heatsink measurement.
The Sprague 5300MF cap is 1" in diameter and this image seem to indicate that the heat sink is taller than the cap.

http://www.computercloset.org/apple1.htm

For comparison here is a Mimeo taken at close to the same angle with a 1.25" heat sink installed. They look the same to me.

http://www.willegal.net/mimeo1-at-an-angle.jpg

Also I have an pretty much edge on image of the Schoolsky Apple 1 (late NTI board) that clearly shows the heatsink as taller than the 5300MF cap.

http://www.willegal.net/schoolsky.jpg

regards,
Mike Willegal

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Re: Introduction - Building a replica

I must agree with Mike Willegal.
I have several pictures from Original Apple 1 too and the sink is deffinitly taller than the capacitor.
But That should not be the only reason to think about !
In fact the cooling of the LM323K is rather poor !
Choosing the smaller sink raises pretty far the risk of the LM323 to become overheated !
Every few parts of a inch higher sink will drop this risk.
A Heatsink with 1,25 inch hight has 25% more cooling effect than a sink with only 1 inch hight !

So taking the taller heatsink is also a question of reliability and expandinmg lifecycle of the LM323K !

speedyG

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In early days I had a lot of money but no time - now I have no money but a lot of time....
the second part includes less friends but a lot more joy on life....

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Re: Introduction - Building a replica

Mike, thanks for the update! From historic purposes, it would be great if we could get a definite confirmation on the height, irregardless of cooling conditions.

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Re: Introduction - Building a replica
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Re: Introduction - Building a replica

Mike WIllegal wrote:

Before everyone goes out and buys 1" high heat sinks, I think someone with current access to an original Apple 1, should recheck the heatsink measurement.

The one that I measured this morning on a non-NTI board is most definitely 1" high. It still has the gold LM323K regulator. I don't recall seeing indications that it has been removed.

I will let others chime in with details on other systems, but it appears that both 1" and 1.25" parts were used. The difference (as noted by speedyG) is significant in the amount of cooling provided (7C at 7.5W from the data sheet.)

http://randomvariations.com/wp-content/uploads/2015/01/IMG_8864_heatsink.jpg

For reference, the other voltage regulator with a heat sink in the image is a replacement.

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Re: Introduction - Building a replica

Thanks Chris, nice photo too!

Online
Joined: Oct 9 2011
Posts: 1063
Re: Introduction - Building a replica

I measured one, a pre-NTI and it's 1.25". This board has had no "work" or replacements.

Here is also a picture for comparison to the height of the caps and other regulator...

Cheers,
Corey

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Re: Introduction - Building a replica

Awesome, Thanks Corey! Seems like both are acceptable, I guess I need to order a 1.25" now...

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Re: Introduction - Building a replica

Following up on the 330 ohm resistor, are the different looking resistors typical?