EPROM - Erasable Programmable Read Only Memory - computer memory

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1702A EPROM

The first (1971) EPROM ( Erasable Programmable Read Only Memory ) 1702A changed computing forever. The 1702A is  Nonvolatile memory chip and does not lose its contents (program) when power is turned off.  RAM (Random Access Memory)  used at the time was volatile - the contents is lost every time power was turned off.  Being able to program the microcomputer and have the program or data stay resident when power is turned off was essential. The EPROM was invented by Dov Frohman of Intel in 1971, who was awarded US patent 3660819 in 1972.

Click on photo to enlarge

1702A EPROM

It is interesting to look though the quartz window of the EPROM integrated circuit (IC) at  the die inside. You can see the little gold wires that connect the die to the pins on the holder.  The quartz window allows the memory to be erased by exposing it to UV light and then it could be reprogrammed. More information about EPROM's "Wikipedia CLICK"



This is a revisit to EPROM's - see my earlier post "Vintage EPROM Memory 1702A -Made microcomputers, robotics and micro-controllers practical 1971 CLICK". 

1987 reciept for 359 EPROM's

In 1987 I purchased a nice collection of 359 EPROM's from Computer Surplus Store for $229.85.  This looks like a good deal today at 50 cents each.

1987 receipt for 359 EPROM's

Date & Price








Click on photo to enlarge

1702A 2708 EPROM

Here  are the 359 contained in 30 storage tubes. Almost all the EPROM's are the beautiful ones in a white ceramic package and gold pins.

This shows hoarding as I indicated in my last Blog.

1702A 2708 EPROM close view

A closer look at some of the 359 EPROM's.

I purchased these 28 years ago with the idea of using them to make a display plaque to put on a desk or hang on the wall. The white ceramic EPROM's with the clear quartz window a very interesting to view and with some additional photographs and history with the EPROM it would be an eye catcher for sure.

You can get a good look by CLICKING on the photo.


As you can see I have not made the displays using the 359 EPROM's and would like some help or suggestion about how to put them good use . Of course I could sell them on Ebay but that would not be much fun. Contact me here with your idea's "Contact David CLICK"

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Some of the EPROM'S  in our inventory are in applications like the board below.
Click on photo to enlarge

menory card 2716 EPROM

I have hundred's or perhaps 1000's more of the EPROM'S in the museum warehouse. Many are in the nice white package.

Here is a typical use of EPROM's - this board contains (16) 2716 EPROM's . The operational program for this computer is contained in these 16 nonvolatile memory chips. The 2716 contains 16K Byte of memory.

Can someone help me identify this early microcomputer board??

2716 EPROM

Better view of the 2716 chips on the computer board shown above.






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A small collection of EPROM'S
Click on photo to enlarge

Intel 1702A EPROM

A small batch of 1702A chips unused in the original Intel Package. The package is also interesting and a collectible item.

Intel 1702A EPROM 

 New unused Intel 1702A EPROM chips.








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Here is a video I made in 2009 about the 1702A EPROM "CLICK"
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David Larsen

I have hundreds of EPROM's in the museum warehouse and many of them are still on computer boards like S100 memory cards. Please help with some innovative and interesting uses for all these beautiful IC's. Still having fun at 76 yrs. 

           .^{"by David Larsen"  KK4WW Computer Collector Historian} 

Vintage Computer Intel MCB8-10 Microcomputer 1972

The Intel MCB8-10 is one of the first microcomputers using the 8008 microprocessor. I am sure there are earlier ones but this seems to be about the first one from Intel. I acquired this microcomputer in 1981 from my friend Robert (Bob) Stone. Bob was on the lookout for memorabilia to add to our historical microcomputer collection. I had known Bob for at least 10 years while he worked at Virginia Tech. He was also pursuing a degree while working.  In 1981 when he purchased this computer he had received his PhD and moved to the Sunnyvale area of California. There were many great shops in the Bay area for computer and electronic hobbyist in those days. The shops were packed with the early microcomputer surplus things from the local Silicon Valley   start up companies.  Remember the microcomputer revolution was only 10 years old starting in 1971 more or less with the first commercial microprocessor chip 4004.  The Apple 1 microcomputer only arrived on the computer genera in 1976.  The Bay area electronic junk shops were full of items any collector today would have absolute euphoria over and think they had died and gone to collector heaven.

Bob was able to purchase this MCB8-10 for me at the Halted Specialties Co., Inc in Sunnyvale CA. for $125.00.  That was a tidy price for those days but this was a rare computer even at that time.  The name Halted Specialties makes me think "Stuff no longer made or sold". 

The microcomputer MCB8-10 First Intel 8 Bit Development  System. This uses the 8008 microprocessor and was used to develop hardware, software and program 1702 EPROM'S for final product design . I do not find much information about this system on the internet. A few other collectors do have them in there collections. I  have several manuals for the system so it is a well documented system. I was able to add the MCS8-10 to my collection in 1981 and it is in very good condition. This is not the first Intel development system however it may be the first 8 bit development system.

 

 Part of control panel with switch register                                 CPU card with memory

This is Nate Cleveland , he works after school with the microcomputer collection doing data entry and web updates.  Nate ( High School student and part time staff ) is holding the 8008 system manual for the computer.  Our LCF Group employs 2 addition part time student office assistants - they are now in college however they started while in High School. These student assistants are a tremendous help with our museum collection and display. The photo at the top of my blog was designed by Student Intern Amber Ingram using the panel from the MCB8-10.

   

This video was made 3 years ago and I do think

my editing has improved.  The Intel MCB8-10

Microcomputer
 Send a Tweet'CLICK' hashtag #KK4WW if you enjoy the blog or have a comment

Photo of Dave in museum display with MCB8-10 and Apple 1. (CLICK)

 

Dr. Robert T. Stone (acquired  Intel Development System in this blog for our collection)  worked with us in the old days of the "Blackburg Group" about 1980. He coauthored this book "Design of VMOS Circuits" with Howard Berlin.  Robert and Howard were authors in our "Blacksburg Continuing Education Series" and wrote several excellent books. 

Appreciate a like on Museum Facebook Page.

 This is one more hat I ware in addition to 'Computer Collector/Historian' .  Bernie Coveney on the left with CD master & me David Larsen with our contract- We commissioned Bernie to write, compose and record a theme song for our "Chantilly Festival Farm" . Bernie produced  great Bluegrass theme music and we will be using it on all our  Chantilly Farm promotional media. I  will also use it as branding for my video's in the future. I already started with my last video "Vintage SCELBI Computer". I will use it here on the blog when I can learn how to add music. "by David Larsen" - Computer Collector/Historian