Many Thanks

I want to take this time to say “Thanks Much”.  It is because of our members that All ThingsDOS has become known the world over for our content, and your feedback.  It is Thea fact that’ we get new members almost daily on our FaceBook acct simply because of our varied content, and free. Software and document downloads.  If you or someone you know wants, or needs information on a specific vintage computer, by all means give them our website info.

As always, we offer the best, free access of vintage software for IBM, Apple and Mac, Commodore, Tandy/Radio Ahacks TRS-80 and several others.  We also maintain multiple operating systems.  Ranging from multiple FLAVORS of BASIC, FORTRAAN, and even COBOL.

Our primary focus has not changed though.  Vintage computers, and vintage computing are still what we want our readers to see as the most important.  Thomas’s vintage computer collection consists of two IBM 5150 systems, one of which utilizes a very rare IBM 5161Expansion Unit a TRS-80 model 4, and Color Computer,  three Commodore 64s. And VIC-20.  Athomas also has an Apple IIe! And aa Mac SE HXDFD which  has been upgraded to 8 MB of memory which was required to install Apple OS 7.6.

And lastly, there are two Compaq Portables which are in need of repaair.

Ed has a somewhat large collection of vintage Apple, and Macintosh systems, including several 128s, a couple of  Mac SE HDFD.

Where almost almost all of Thomas’s computers are in complete working order, Eds computers are a different story, and need various repairs in order for them to become useful.

Regardless of the condition, both Thomas and Ed work on almost every make and model of computer that has ever been sold in the U.S.

So if you, or someone you know needs computer work of any kiind, please give us a call.  You’ll be glad you did.

c

 

 

 

 

 

 

 

IBM 5161 Expansion Unit – The Components

During my time as a member of the Vintage Computer Forums, and of course, after learning about the existence of the IBM 5161 expansion chassis, or unit whichever you prefer, I have been fortunate enough to have made numerous friends. Most of the friends I’ve met have some knowledge of the expansion unit, but there are those who have no clue.  I have to admit, learning what I have in regard to the expansion chassis took some time.  Most of it, before actually acquiring my own expansion unit.

It was during the time I was researching the 6161 for myself that I learned about what the expansion unit was, what its intended purpose, and most of all, what makes the expansion unit what it is. All-in-all, the expansion unit isn’t all that complicated.  And, while I won’t be going into any of the most technical areas in terms of what makes certain components work, I will provide a brief description as to what each component is, and its place in a working IBM 5150 PC, or IBM 5160 XT installation.

To begin, let me introduce the components that make up the IBM 5161 expansion unit, model 1. (You will learn the differences between the model 1 and model 2 as you continue reading)

  • Case
  • Power supply
  • Planar or Back Plane
  • Internal hard disc drive
  • Hard disc controller
  • Extender card
  • Receiver card
  • Connecting cable

 

As you can see here, there aren’t a lot of items that make up an expansion unit. There are however a couple of key differences between a Model 1, and Model 2 units; most notably, the inclusion of an internal hard disc drive and controller.   Model 1 expansion units were manufactured with the 5150 PC in mind.  Since the PC initially had no provision for the inclusion of an internal hard disc, and the PC also typically did not have a strong enough power supply, the expansion units, models 1 included a 130 watt XT power supply unit, or PSU.

However, here is where the primary differences between the different revisions come into play.

IBM 5150 PCs included only five (5) ISA expansion slots during their manufacture. In fact, no REAL IBM 5150 PC had more than five.  So an expansion unit built for the 5150 had to include at least one internal fixed disc.  One full height, 10 Mb MiniScribe hard disc was installed, along with a Xebec fixed disc controller.  One additional fixed, or hard disc drive could be added to the expansion unit for added flexibility by adding the additional storage space.  With two internal hard discs, storage capacity could be doubled, tripled, or by adding larger capacity hard discs, multiplied to include as much as much storage as the use desired or afford.  Keep in mind, that during the time of their construction, 10 Mb hard discs cost nearly as much as a new car!

IBM 5160 PX/XT systems were by design, built to include one internal floppy disc drive, and one fixed, or hard disc. If an XT user were to purchase an expansion unit for their XT system, the expansion unit they would purchase would, first of all be less expensive because it did not require that a fixed disc or controller be fitted, or included.  Indeed, it was recommended that the hard disc drive and controller were to be removed from the 5160 XT and compatible systems and moved over to the expansion unit.  This saved the consumer some money at the time of purchase.  However, the user could still add an additional hard disc for expanded storage.

Regardless of which expansion unit was purchased, Model 1 and Model 2 expansion units had eight expansion slots. They both used the very same case, planar, power supply extender and receiver cards.  The only real difference was whether or not an internal fixed disc, and appropriate controller, were included.

Let me begin now by looking at the individual components that make up the 5161 expansion unit.

 

  • The case

 

The case looks almost exactly the same as any other IBM 5150, or 5160 computers. IBM chose to keep the same case design for simplicity purposes, as many of the same components that make up a 5150 PC, or 5160 XT and the expansion unit are the same.  Therefore it made sense to stay with the same case design.  Plus, by staying with the already proven design scheme, there was a particular continuity when assembling an IBM 5150+6161 or 5160+5161 system.  By having both the computer and expansion unit look the same, it was easier to maintain a single inventory of let’s say, the metal case upper and lower; the plastic bezel, etc.  In reality, the only things that had to be unique for the expansion unit were the labels, and badges that indicate which unit it was initially designed.  Take a look at a 5150 PC for instance.  The front bezel is the same as the XT. The same goes for the power supply, and case materials.  The only differences were in the case badges.  For the 5150, the badge reads, “Personal Computer”, where the XT’s reads, “Personal Computer XT.” The badge on the front of the expansion unit reads, “Personal Computer Expansion Unit” regardless whether it was a Model 1 or Model 2.

  • Power Supply

 

The next item on the list of components is the power supply, or PSU. In 5150 systems, the power supply was limited to only 63 watts!  In order for the 5150 PC to have enough energy to power the computer and a hard disc drive, the PSU needed to be rated at 130 watts or greater.  Any user who opted to add in a fixed disc to their 5150 systems had to also upgrade the power supply in order to have enough energy for the system to run.

However, for the 5161 expansion unit, IBM chose to use a 130 watt IBM PC/XT power supply. This was necessary to power the expansion unit and its internal ISA expansion cards, and the use of up to two internal hard disc drives.

  • Planar or Back Plane

 

The planar used by the expansion unit is another one of the “off-the-shelf parts IBM chose to use in constructing their PC line of computers and is in no way a proprietary unit. The primary layout is the same as a standard system board, but without any of the logic circuitry required by a full-fledged computer mother board.  Instead, there is a standard 12 volt power connector, 8 ISA expansion slots, and little else.  Remember, early PC’s used ISA slots for any add-on associated to the computers construction and operability.  In a standard IBM 5150, two (2) of the computer’s five (5) 8-bit ISA expansion slots were already used.   That left little else in the way of upgradeability.  In addition to the computers floppy controller, and video controller things like a memory expansion, parallel and serial ports used all of the computers available expansion slots.  So adding a hard disc, or game controller were relegated to the expansion unit.  Some users worked around these limitations by buying combination expansion cards; like the AST Sixpack Plus which included, a clock, calendar, parallel port, asynchronous serial port, Game controller port, and a memory expansion.  These expansion cards went a long way in freeing up resources in the 5150 PC, for adding in a hard disc controller, but for those who needed even more expandability, the expansion unit was really the only option.  Having eight (8) open ISA slots to add items such as a  modem, or LAN adapter, in addition to additional serial ports, meant the difference between having a computer one could work with, or having to work with multiple computers to do the same job.

  • Internal hard disc drive
  • Hard disc controller

 

As mentioned previously, purchasing a hard disc drive during the early 1980’s was a very expensive proposition. Buying two hard discs was almost unheard of in the private sector.  That meant that almost all of the IBM 5161 expansion units were purchased by small businesses, and adding an additional fixed disc or in number was done by larger corporations and those businesses who absolutely needed the additional storage capacity.

Still, the requirement for at least one hard disc is the primary reason the expansion unit was developed by IBM in the first place. Colleges, and the educational sector accounted for the purchase of a very, very small percentage of expansion units, as operations, and educational usefulness could be handled by the 5150, or even 5160 XT computers, outfitted with dual floppy discs.

Hard disc drives, being as expensive as they were, were also used in locations where more permanent storage of records was needed. It is that reasoning that one hard disc was included in those expansion units which were destined to be connected to the 5150 series of computers.  Since IBM began including a fixed disc in their XT line of computers, including one in the expansion unit was seen as redundant.  However, by allowing the expansion unit to use more than one hard disc, and one with more storage capacity than the 10 Mb MiniScribe drive they initially chose, they allowed the computer user to add as much storage as they needed, or their pocketbook would allow.

By allowing, or including one, or more hard disc drives was important, none could operate without the prerequisite controller card. Xebec, Western Digital, and others soon made appearances in expansion units as newer larger hard disc drives were added.  The Xebec controller was just not sufficient at controlling more than a small handful of drives.  Manufacturers of hard discs would often recommend other brands of controllers which were compatible with their drives, or included a controller that would drive not only their own hard disc, but earlier drives as well.

 

  • Extender card
  • Receiver card
  • Connecting cable

 

 

Both cards, and the connecting cable are required in order for the expansion unit to function with the PC. Regardless how many of the other components are available and assembled, if the extender; which is installed into the PC, the receiver; which is installed into the expansion unit; or the cable to connect the two.  The cable is described as follows:  a 56-wire, foil-shielded cable terminated on each end with a 62-pin D-shell male connector.

One of the most commonly missed components of the IBM 5161 expansion unit is in fact, the extender card. One reason for this is that while many complete systems are placed in storage, it is often only the PC that is either given away, or sold.  Most often, the extender card is found in the PC, and discarded.  We now have an orphaned expansion unit.  Then when the expansion unit is later found, it is missing the extender card, and cable.  But while the cable can be replaced, the extender cannot.  If an extender card is found, it must be an authentic IBM part, or it will not work.

Currently, there are less than 20 IBM 5161 expansion units in complete working order! That is important!  That is – Less than 20 expansion units in complete working order!!! The primary reason for the possibly many others to not fall into that category is simply because of the missing extender card.

All other reasons for expansion unit failures are insignificant in number. It must be mentioned though that if one were to possess an extender, receiver card, and cable, using this list of parts, one could theoretically build their own expansion unit.  Most of the parts are freely available online.  Specifically, the power supply, 8-bit 8 slot passive ISA backplane etc.  Once these components have been assembled into an IBM PC/XT computer case, it could work.

 

I have seen one, and only one of these home built expansion units work. It is NOT being counted as one of the original IBM expansion units, because the only items from an authentic IBM parts list are the extender, receiver, and cable.

If there are any questions regarding the assembly of an authentic IBM 5161 expansion unit, or in its operation, please feel free to contact me. I do NOT however, have access to spare parts, but I can assist in completing your own build once you have a workable unit.

Thank you for reading.

 

 

 

 

All Things DOS Facilities Update

Ed's new computer workbench

Ed’s new computer workbench

A couple of weeks ago Ed won two portable computer desks at action from the
Clark County School District. He paid two dollars each for them.

This weekend he has set the first up as a workbench. A place he can work on
and repair vintage computers. He had installed a light with a large
magnifying lens so he can see what he is doing. He still needs to order and
install antistatic mats to protect the electronics.

Ed plans to set the other up as a soldering station. Where he can work on
boards that can’t be replaced. That means he needs to get a second
magnifying light and a second antistatic mat. Ed has already bought a nice
soldering station he just needs to get the soldering pen to go along with
it. These two desks will be moved out to Ed’s workshop when and if he gets
it cleaned and fixed up.

Ed’s workshop will also house the majority of the All Things DOS vintage
collection. With the exception of a few key system that will reside At Tom’s
house. In time a full virtual museum will be posted on All Things DOS. This
virtual museum has been started but has a long way to go. At All Things DOS
we are always looking for additional vintage systems. Though Tom has most of
what he wants for his personal collection. Ed loves working on these old
systems and hopes to see the collection grow.

While Tom studied programming in collage he is content to sit at a desk making the computers do his bidding. Ed on the other hand studied electronics and needs to get his hands dirty by tearing into and restoring these old systems.

Currently, the majority of Tom’s computers are in complete working shape, and
Ed is working to complete the last two machines in Tom’s assorted
collection; the Compaq Portable 2, and a new tweener, a Packard Bell Force
Legend mini tower which runs windows 95 through a 75 MHz Pentium processor
and 8 MB of RAM. Once these computers are returned to Tom in working
condition, Tom will have only one more micro-computer to complete his small
collection, and Ed can focus on his computers.

 

Why do people collect old computers?

Well, to answer that question, one must ask why the interest?  Is it nostalgia? Or because you just like to collect old things, or are you into it for the money? Finally, is the collector attempting to obtain a particular computer from their past, but could never afford when new.

Let’s answer each one of these questions one at a time.

I can tell from experience that most people don’t get into vintage computing for the money.  Very few members of the Vintage Computer Forums and other online vintage computer clubs have much money to support their hobby.   This is why in many cases; it could take two to three years, or more, depending on the availability of various computers/systems/peripherals. Another reason some people, myself included people collect old computers, is to obtain a particular machine, which in the past was just entirely too expensive; for instance, the IBM 5150, IBM 5160 and IBM 5170 systems.  .

My own collection contains 3 such computers; the IBM 5150 + 5161 (Which is a story all unto its own), another IBM 5150 sans expansion unit, but one that came with another very useful update in the form of a completely electronic “hard disc” of sorts.  The upgrade is known as an XT-CF Lite. The last computer in this list of expensive models is another IBM, this one, an IBM 5160 XT, which was IBM’s first ever computer that contained it’s own internal hard disc.  I also own a Compaq Portable 2. These systems could reach as much as $19,000 in 1983 dollars. That works out to $58,530.96 in 2013 dollars as calculated on Dollar Times web site. Even the least expensive of these three computers was priced at $699 in 1984, which calculates out to $1,859.69, using the same tool. Given that the minimum wage back in the early 1980’s was only $2.35/hr, purchasing a new computer was an incredibly expensive endeavor. 

To add even more fuel to the debate; many hobbyists collection profiles focus entirely on one brand, or model within that brand.  Other collectors; like me, are much more nostalgia minded. These collectors gather computers they have had direct experience with, and which systems have had a direct input into the path their lives would eventually take.  For example, my own collection consists of 5 different computers, over 3 brands.

  1. IBM 5150 + IBM 5161 Expansion Unit
  2. IBM 5160 PC/XT
  3. Mac SE HDFD
  4. Compa1 Portable 2
  5. TRS-80 Model 4

Note:  My collection at one point, contained 12 different computers over 4 different brands.  Since then, I have refocused my collection and am now only collecting vintage IBM systems, from the venerable 5150, dual floppy model, to the 5160 XT, the first IBM to include an internal hard disc drive, on to the IBM 5170 AT which is the first IBM to break the 640Kb memory barrier, and finally, an IBM 5155, which is basically like the 5150, but was manufactured to be a portable computer.  .

There is 1 computer left in my wish list; a Series 1 TRS-80 Micro Computer with original B&W monitor and Radio Shack tape recorder. (Much to my wife’s delight! She does support me and my hobby, but I know she’ll be glad when I don’t bring any more computers into the house!)

The point I am attempting to convey here, is that vintage computer collection can be as varied as there are computers and people who collect them. This doesn’t stop at the computer hardware either.  There are a large number of vintage computer emulators available for download on the Internet. These emulators can make locating and gathering software easy, and enables software to be written for various floppy disc formats. In addition to emulator sites, there is also a huge number of resources for locating diagnostics software, business and productivity applications, and, literally tens of thousands of games.  As a testament to this, All Things DOS has over 30,000 game titles in various formats, written for different systems in our archives.

The next area where collectors look is in the area of parts and peripherals, such an AST Six Pack, and Six Pack Plus multi cards, modems, LAN adapters, sound cards, and any number of available upgrades for their systems.  One good resource where I have found like-minded collectors of vintage computers, software, and peripherals is the Vintage Computer Forums. Members of the forums are very knowledgeable, and extremely helpful. Some are also extremely generous as well. I have been given several computers from a couple of the Forums members, as well as information on how to obtain other resources, and lastly; I have gotten very good deals for some of the peripherals used in some of my systems; especially the IBM 5161 Expansion Unit which I was able to purchase and outfit to original specs for only $125.00 while at the same time several expansion units were selling on E-Bay for well over $850.00!

To close this blog entry; a final note on All Things DOS.

A lot of these resources can be found on www.allthingsdos.com.  This web site is the brainchild of Edward Hall, and Thomas Chavez; two guys who have been best friends since kindergarten in 1965.  They have been best friends ever since they met, and now share their love for vintage computing with each other and by creating all Things DOS for others to enjoy.  But, while Ed took a more professional and somewhat more direct road to computer maintenance and construction by joining the Air Force; Thomas on the other hand took a different approach, by going to college at UNLV in Las Vegas, and the Las Vegas Business College, eventually earning a degree in computer programming.  Sadly, Thomas’ education did not include computer maintenance. That would later become a hindrance, since the majority of computer work now includes assembly; especially when it comes to vintage computers. Thomas’ education completely skipped over that aspect of the computer industry. Still, Thomas made a good career working as a technician, and later supervisor with UPS Technical Support, based on his ability to teach himself and others. Thomas worked for UPS for over 16 years before disabilities became too much for him to continue working 8 hour days. Now, his hobby of vintage computing keeps Thomas busy. He can work as much, or as little as he feels, and because of this, Thomas can keep his mind active. Not only has Thomas amassed a small collection of computers, as outlined above, but he continues to learn, and re-learn much that he has forgotten over the last 30 plus years working with computer programming. Now, Thomas reads users manuals, and operation guides for the various computers he owns. Thomas is learning about maintaining the hardware and peripherals as he obtains new equipment, and still Thomas goes to Edward when something comes up that he doesn’t know, or understand.

Ed enlisted in the United States Air Force while still in high school, going into active duty just months after his graduation. Ed joined as a 305X4 Computer Systems Technician where he attended school at Keesler A.F.B. in Biloxi, Mississippi. This is where Ed learned the basics of electronics, computer fundamentals, programming, and went on to specialize in the 465L Data Display Central; a computer that was older than he was, and which at the time still utilized vacuum tube circuitry.  Ed now functions as the Webmaster and Techno-Geek for All Things DOS. This is where he has aided Tom in the creation of their web page of the same name, and where Ed also serves as the primary technician, maintaining all of their vintage/collectible computers and systems. Without Ed, there would be no “All Things DOS, except in Tom’s mind, where the dream would languish and eventually die.

Together, Ed and Tom make up All Things DOS, where both have their interests, and ongoing realization of a dream that Tom shared with Ed nearly three years ago, in 2010, as Tom began obtaining his first vintage and collectible computers.

Today, both Ed and Tom can be found working on either one of the computers, or plugging away updating our web page; each working in their own areas of expertise.

While Ed is the brains behind our web page, it was Tom’s idea that started it all, and which eventually became the brainchild we call All Things DOS. Together Edward and Thomas make a great team.

Please feel free to contact either of us at any time for assistance in your technical issues, or guidance in how or where to begin your own personal collection. We are always there to help.

We hope you enjoyed our site.  Not all of our updates are easily seen.  We’re always adding new programs, or content.   Come back often.  Remember, registration is always free.

Join the All Things DOS team

Do your friends and neighbors come to you when they have computer problems? Does you’re significant other question your stock pile of old computer parts and systems. Are you considered an expert on one or more vintage computer systems? If so then All Things DOS may be looking for you.

All Things DOS is looking to add systems vintage computer experts. These are volunteer (non-paid) positions we are looking to add system experts who will share their love and knowledge for vintage computers with others. Your responsibilities will include writing blog post about your chosen system(s). creating system specific pages, with information, photos, tips, tricks, and advice. Where possible answering question posted by our membership about your specialties.

Initially, your posts and pages will need to be reviewed by Ed & Tom to insure they meet the All Things DOS standards.

All Things DOS is not just about DOS computers. Our current collection includes the Tandy TRS-80 CoCo, Apple ][e, Mac 128, Commodore C-64

No you do not need to live in Las Vegas, you don’t even need to live in the United States. In fact we would love to get team members from all over the world with expertise on systems specific to the area.

We are specifically looking for

  • Mac or Apple expert
  • Commodore and Amiga Expert
  • Tandy Computer Expert.
  • Experts in any vintage computer system.
  • Even experts in odd systems like the Amstrad.
  • Mini and mainframe systems like the DEC PDP-8/11, or Honeywell
  • Program experts in vintage programming like Basic
  • CP/M and UNIX experts.

If you are interested in helping to make All Things DOS please contact Ed for more information (702) 546-9003

Announcing the All New! All Things DOS Store

At All Things DOS we are pleased to announce the addition of our on-line store. Tom and Ed started All Things DOS with the idea of sharing their love for vintage computing with the world. We now have a growing membership and hope to see this continue to grow. We have added content including thousands of program files, and a growing number of system resource pages. Recently we have been approached by a few of our members requesting to buy our software collections on Disk. With this in mind All Things DOS has opened our on-line store. Currently it mostly offers Software Collections but we are working to expand it into other areas. Watch us as we grow. check back often to see what we have added. The operation of this site is not free! with Web hosting, domain name, and other fees, it gets expensive for two friends both of whom are disabled and living on limited incomes. We ask that you help support this site buy visiting our store, our sponsors, and our Amazon Store Front.

Category:

New Software Collection Added; Amstrad CPC

Lets face it Ed has gone a little far afield on his latest software collection. During the 1980s while living in England Ed had an Amstrad CPC system. When Ed discovered this collection he just had to add it. Of course, Ed no longer has his Amstrad so we have no way of testing these files. Never the less, here they are for your pleasure.  http://allthingsdos.com/amstrad-software/  If you download these and give them a try please let us know how it goes.

Amstrad Computers

Apple Gallery:

 

Commodore Gallery:

DOS Computers

Compaq Gallery:

IBM:

TRS-80 Gallery

Software Uploads

All Things DOS has completed the upload of over 4,000 Apple ][ disk image files this in conjunction of over 10,000 image files for the Commodore 64, thousands of early IBM programs a small handful of Lisa image files, and Vic-20 images  These file have been made available to All Things DOS site members. All Things DOS has not tested these files. We hope to start playing with them in the near future. Enjoy our growing collection.

Commodore 64 Programs

All Things DOS is in the process of adding hundreds of Commodore 64 Programs to our large collection of Vintage Computer Programs View our C-64 Program page for the full listing of Commodore 64 program disk images. We have not yet tested any of these files one we have we will add information on how best to decompress them and copy them to a media usable for the commodore 64. These file are all available in the Public Domain All Things DOS  has only assembled them into a convenient collection. Please contact us if you would like to buy a DVD containing all these files. You may also contact us about buying copies of our other program or manual libraries on DVD.

More Apple II programs

 

Today All Things DOS added another than 100 disk images to our Apple II library. There are still 1,000+ images to go. If you haven’t already done so sign up and take a look at our growing library of early computer programs. Don’t Forget to check out the Commodore 64 library and the IBM collection.

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