DB-19: Resurrecting an Obsolete Connector (2016) | Hacker News Reader

DB-19: Resurrecting an Obsolete Connector (2016)

bigmessowires.com

170 pointsspamizbad48 comments

There were never DB-9 connectors; they were DE-9s.

The "DB-this" and "DB-that" naming originated by ignorant analogy with the (correctly-named) DB-25 connectors that the DE-9s were replacing. Hint: The letter after the D is the size. DBs had room for two rows of 12 and 13 pins on 1/10 inch centers, on down to DE with room for only 4 and 5 pins with that spacing. Later, the DE shell was used with closer spacing for three rows of pins, for video monitor cables.

Once enough ignorant people took to calling them DB-9 and trying to buy them by that name, the vendors started hawking them that way.

https://en.wikipedia.org/wiki/D-subminiature#DE-9

One thing of note is that the pins are not exactly on 1/10 inch centers, the spacing is slightly larger than that.

> “But wait!” says the well-intentioned blog reader, “this web site over here has DB-19P connectors for sale right now!” They may claim to have them, but trust me, they don’t. Electronics parts suppliers seem to make a habit of listing available items that aren’t actually available, whether out of laziness or as an intentional bait-and-switch, I’m not sure. But if you call them or try to actually order the parts, you’ll find they don’t exist.

This reminds me of Things I Won't Work With mentioning Chinese chemical supply houses that list prices for a gallon of a specific chemical, when there probably hasn't been that much made in all of human history together, and if it were made and brought together in one place, the resulting crater would be visible on Google Earth.

Brings back memories. Years ago, I came across a need for a DB-19 cable and had trouble sourcing one at a reasonable price.

I arrived at a somewhat less robust solution which involved a DB-25 cable and a hack saw.

That’s not quite as ugly as a serial cable in a production dialup mail pick up box I found once. Someone was clearly missing a DB25-DB9 cable for the modem but had a DB9 shell floating around. They made a cable with some telephone wire, stripped the ends, folded them and rammed them into the DB25 connector holes on the modem. The other end was solder buckets and they did the same and crimped the thing. It worked. Until it didn’t. Then the modem and the cable had to be replaced because the connector was buggered.

This of course failed and I discovered the situation on Friday at 5:30pm just as the local Maplin had shut.

Amiga uses the DB-23 for monitor, I don't believe it's made anymore, however, it appears you can still order it. It's not as unusual yet as the DB-19.

(And now that you can order, for the first time, a new Amiga with an open source operating system, you don't need the DB-23 anymore, it uses HDMI. Vampire v4 stand alone. No affiliation, just fascinated.)

Where? Isn’t V4 still unreleased?

It's pre-order only so far I think. Here:

http://apollo-core.com/knowledge.php?b=1&note=23461

There was a good article about it here that was on HN a few days ago:

https://www.forbes.com/sites/marcochiappetta/2019/10/22/the-...

Disclaimer:

I may have mixed things up, I'm not closely monitoring this, but I think you could pre-order it somewhere. Maybe it was only existing customers or something, it was something I saw on the FB group I think!)

The Atari ST line of computers also use DB-19 connectors for their external ACSI interface, usually used for connecting hard disk drives. ACSI is Atari Computer Systems Interface, similar to SCSI.

The blitz copier used that, iirc. Fantastic noises a pair of floppy drives can make when running like crazy.

Here's a photo of a 520. It's the "Hard Disk" port all the way on the right.

https://upload.wikimedia.org/wikipedia/commons/c/c0/Rear_por...

It was possible to hand-make a replacement for Atari's external floppy drive (round DIN connector on the right) because Atari wanted too much money for theirs. Having two floppies meant that compiling went from several disk-swaps to no-swap happiness.

The project this was made for (FloppyEmu) is awesome: https://www.bigmessowires.com/floppy-emu/

The Mackie Onyx 1640 https://intranet.bloomu.edu/documents/tech/ims/Manuals/Macki... has two DB25 connectors.

But DB25 is still very standard, thanks to all kinds of legacy serial communications hardware still in use. Those used mainly DB-9 and DB-25 connectors.

Indeed, DB25 is all over pro audio still. It's mechanically fragile compared to elco (or whatever other multipin) or just using a lot of XLR... but it's easy to get off-the-rack or custom DB25 audio cabling.

Well if you use proper old school Metal Shells, shrink wrap the connections and screw them down DB25 can be robust.

DSubs are robust when they are connected, but fragile in applications that require frequent reconnections.

Ah I see what you mean

There are vast quality differences in D-Sub connectors. Industrial-spec ones are quite durable, although of course they still have the robustness issue of relatively thin pins that can be bent or broken easily by whacking the connector on the edge of a table or something like that. That doesn't tend to happen with e.g. XLR, Speakon, Hartings or Multipin connectors. However, the pin density of these is also quite a bit lower...

In my experience the higher-spec DSubs are actually more prone to broken pins. The connector is actually meant as cable harness connector for aerospace-ish applications, the whole concept of dsub shells and using it for external cables is largely an IT industry invention that happened few decades after introduction of the connector itself. Micro ribbon (ie. “Centronics”, “Telco connector” and what not) is actually meant for repeated imprecise insertions and has comparable pin density and electrical specification, but thickness of its shell is at the edge of what is practical for various EuroCard-derived backplane systems (which includes PC cases) and thus DSub won.

Yep, that's the TASCAM [1] audio connector which is DB-25 and super common in the audio world. Traditional audio uses AES [2] using either XLR or BNC connectors and only carries two audio channels. The TASCAM cable carries far more channels and, if using digital AES, there is no downside since it either works or doesn't.

[1] https://en.wikipedia.org/wiki/Tascam_Digital_Interface [2] https://en.wikipedia.org/wiki/AES3

It had two DB25 connectors. That's an old analog mixer from 2004. The Mackie webpage doesn't even list products that old.

Of course, their current digital mixers don't have any D-shell connectors.

Well, it's still around, that's for sure...

https://apogeedigital.com/products/symphony-io/configuration...

I mean, I can't afford $5K for that, but it's there.

This is an extremely common and widely used standard for analog and digital connections for pro audio. I just wired in a bunch of DB25 gear last week. For low end / mid range digital stuff it is more common to see ADAT optical digital vs DB25

What would the world look like without China ? There is literally nowhere else to go to build something today...

That's why we're living in a time of phantom prosperity.

An analogy is when celebrities make a million dollars and think that they are rich, only to spend it all and find that they owe half a million dollars in taxes. After selling their possessions and settling with the IRS, they sometimes end up with nothing.

The fallacy is thinking that since you have something in hand, you can always get it again.

True prosperity would be more along the lines of true wealth.

For example, having a business or investment that pays dividends for life. $1 million is actually worth about $50,000/year at 5% interest, and in practice probably less.

We should be living in an era where our basic needs and trivial manufactured goods like a DB-19 connector are readily available or easily manufactured from scratch. We shouldn't have to buy in large lots from mysterious manufacturers halfway around the world.

As a child of the 80s, I'm seeing a lot of shiny consumer electronic goods but the almost total loss of any kind of autonomy. We can't do things anymore that used to be taken for granted, like repair our own tools or cars, barter medical work for venison, work part time and go to school, you get the idea.

I'm hopeful that this might change after the next recession though, kind of like how everyone pulled themselves up after the 2008 housing bubble popped and got the mobile/social and gig economies moving. Kind of sad if it comes to that though.

> barter medical work for venison

exactly where did you live in the 80's?

Where I grew up about 2 hours north of NYC, that sort of thing was not uncommon in the 80s.

In that timeframe I had a heart condition. The local cardiologist I saw was really into hunting. He even had some trophy bucks and bass mounted on the waiting room wall. His wife, a nurse at the hospital I was in for a week, described him as "a good ol' boy". It wouldn't surprise me if he at some point took some hunting related payment instead of cash. Medical insurance, while common, was less of a thing back then and barter was quite common in the community. Mostly people trading boats, trucks, rifles, and appliances with each other but services happened too. It was the type of informal arrangements that work in areas with high social cohesion.

Sorry ya without context, I don't suppose my comment made sense.

I grew up in Idaho and went through a couple of recessions. Most of the TV/movies from that time like Family Ties and Ferris Bueller's Day Off portray it as prosperous, but it was really more like South Park.

My dad practiced dentistry for many years but due to some house fires and other setbacks, we didn't have money until I was about 15. So I grew up eating a lot of lamb, deer, elk, farm fresh eggs, etc that he got when he traded out dental work because nobody had much money.

So what I was trying to say is, real prosperity to me would look more like if the 80s and 90s had continued so the US still had its manufacturing base today. A bit more like how Germany has prospered.

Instead we have the appearance for prosperity for most, but the bottom income half of the US is really struggling right now with multiple jobs, high debts, and not nearly as strong of a social safety net as we had then. So I question why that is necessary when some people are doing so phenomenally well. To me, America lost its way after the dot bomb around 2000 and never really recovered. Maybe I'm reaching though, if I'm seeing conspiracies just because we can't find a discontinued connector, which I fully admit haha.

If it weren't for China, someone else would be building these. Take China away instantaneously, and there'd be problems. But the reason there's no where else to build something like this today is because China does it better[1]. Without China, (and with enough time) it'd be someone else.

[1]: According to market forces.

I.e does it cheaper. "Better" is optional, not necessarily available. But surprisingly often is...

The problem is "enough time" can be a generation. For example, France didn't build any nuclear power plants for two decade, and when it finaly build a new one (EPR) it takes three time more time an money than expected, because no one no anything anyymore on building a nuclear power plant in France ....

The Amiga uses (it's still alive! DB23 for its RGB signal. I have a hacksawed connector which works fine :)

Makes me wonder how conservation work in museums is going to be done on artefacts that were industrially manufactured. Imagine 200 years from now somebody has to repair an Apple II with a rusted out DB-19 port, where are they going to find the mechanical drawings and would the machines needed to make new ports even exist still? My hope is that 3D printing matures in time for this to not be as a big if a problem.

For a serious look at this exact phenomenon I'd highly recommend the Apollo AGC restoration done by Curious Marc and others for the 50th anniversary. They had to redesign and rebuild a few connectors down to the pins to actually restore things. There's also a lot of other crazy stuff they had to do, including putting some of the electrical modules in a milling machine and drilling them out to replace bad parts.

https://www.youtube.com/playlist?list=PL-_93BVApb59FWrLZfdli...

particularly parts 10-13 I believe are where the pins and contacts come into play.

Except Marc's team actually had highly detailed mechanical drawings of those parts, so the only hard part was finding someone who could manufacture them. Thankfully they had connections in that area.

Yea, that definitely made things immensely simpler but it's still a good reference for seeing what kind of problems happen. I'd also imagine that for most connectors you aren't going to need nearly as robust or detailed drawings or data about them to make something that will work. In this case they also wanted something that would mate up perfectly without any possibility of damage or excess wear on the connectors.

To be fair, it's possible to handcraft one or two connectors... might take some time, though.

200 years from now we'll just scan the originals (or bring back the digital archives) and 3D print them on our multi-material micrometer-resolution printers.

For a problem like this, I wonder if it would be easier to just make a replacement cable for the DB-19 connector on the computer itself, which replaces the external DB-19 with some other more-common connector (along with the cable that goes to the PCB inside), and then the device you're selling uses a cable that matches that.

I wasn't aware the Atari ST's used those. I remember the 8-bits one had a similar, but just different enough connector for its SIO expansion bus.

Why does this post not have upvoting buttons?

You probably already upvoted (or downvoted, accidentally?) it. If it says "unvote" under the link you can click it to get them back.

I have no unvote either

Just for this post, see it occasionally. I know it's a thing for YC hiring posts, but I've seen this happen and was wondering the rules that apply

There are three of them like this on the front page for me now. I upvoted another and it appears normally.

A/B testing?

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