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UPS was Kind to Me Today

A box containing 250 of the Molex connectors arrived today so now I’ll be populating lots of SS-50 boards again.  They arrive in trays of 56 connectors, two of which are here:

Speaking of rebuilding my inventory, I’ll have a lot of items for show/sale at Vintage Computer Festival East in New Jersey, May 18-20.  There are a few vintage computer festivals around the country, but the one in NJ is definitely big compared to the rest.  Besides being a great time to see and use our products, there are dozens of excellent displays of vintage computer systems, so it’s a great chance to see a lot of the systems you missed or couldn’t afford at the time.

I’ve been using github to hold most of the engineering documents for our products, including CAD files, source code, documentation, etc.  In the near future I’m going to start making some of the projects public, particularly the source code to the SD shield, our extensions to SBUG, xSWTBUG, the KIM Clone monitor, etc.  Customers have noted that some of the code on the thumb drive is older than what’s actually shipped with products so it makes sense to just put the code in public git repositories so the latest is always available.  I’m also hoping others will pick up the code and do more with it.  Despite my enthusiasm to write code, design hardware and produce a few dozen products, I also have a day job, family, and sometimes need some down-time to play with other interests.  Having the code public means others can free access to it and can put their extensions on-line for others.

This weekend I’m helping my wife with a STEM weekend at a local Girl Scout camp so the soldering iron will be turned off most of Saturday.


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It’s Been Quiet Here

It’s been a while since I posted anything and people are emailing asking what’s up, so this is an update.  My day job is still really good but taking a lot of time, so there are evenings when Corsham Tech just doesn’t get the attention that it used to.  We’re still here, just not spending quite as much time as in the past.

A few months ago I talked about a shortage of parts, and we’re happy to announce most of the parts backlog has been filled, except for the dreaded Molex connectors used on every SS-50/SS-30 board.  A large order was supposed to ship the end of February but the vendor informed me that the manufacturer (Molex) won’t ship until late May.  That’s too long, so I looked at more expensive  sources and found big companies like Digikey also have zero in stock.  A bit more searching and I found a bunch and ordered a few hundred.  My expenditures on Molex parts is in the order of $700 for the year so far.

The number of products on the web page is a lot more than I had ever planned, and a few of the low-selling items will disappear.  However there will be some additions like those hard to find parts needed for some of the boards I sell, such as the MC14411, MC6875, 74HCT145, etc.  There will also be packages of those parts so someone can buy some of the least common parts along with blank boards.

I’m starting to spend more time with some of my other hobbies again.  Over the last few years I’ve made maybe 100 contacts on my ham radio, compared the few thousand a year in years past (ie, contesting).  I keep hearing more about the JT8 protocol and have finally gotten it going, hoping to spend more time on it this weekend.

Another old hobby is robotics, mostly spurred on by my son in college (Drexel) where he’s taking a cool robotics course this quarter.  The last time he was home he got my wife and I diving into our old robot stuff again, me doing some work on home-built bots, while my wife got back into the Lego system.  She uses them for STEM demonstrations for Girl Scouts, but is doing more with them now.

There is one new revision to an existing board coming.  I have the prototypes and just have to site down and do more surface mount soldering and then see how it works.  Nothing major, just fixing a problem I didn’t like in an existing board.



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Parts Availability

One of the difficult parts about building accessories and reproductions of vintage machines is that some of the parts are getting more difficult to find.  Over the years I did few prototypes using modern CPLDs and FPGAs but always opted to stick with 74xx series parts because then anyone could understand my designs and fix them if something went bad.  It was also nice to use parts that were available in that time frame.

More and more of the parts I use are getting difficult to find in the surplus market, some of them are going up in price, and others aren’t available in small quantities at reasonable prices.  This is forcing me to reconsider going to a modern CPLD for some designs.  A modern CPLD is in the $1.50 range, which can replace a few parts that cost $5 or more, and are readily available from many distributors.

During a recent session of building SS-50 boards, my supply of female Molex connectors ran low.  That’s usually not a problem because several vendors normally keep them in stock, but when I went to order more, all but one of my supplies said they will no longer stock that part and had none in stocks.  The one remaining vendor had none in their inventory but will be getting more in late February, so I ordered more than 300 of those connectors.  This is a concern because there are no second sources of this very old connector, so if the manufacturer stops making them, the available supply will disappear.

I normally have a large stock of assembled products ready to go, but until the new connectors arrive in about six weeks, some SS-50 products won’t available once the existing stock is sold.  When the connectors appear, I’ll start building boards and increase the inventory of assembled products.