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What cheap/junk computer/terminal to be used in a dusty room as a terminal for PDP8?

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rorypoole

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I am working on building a pdp8 straight 8, and one thing it will do is run a CNC router, the pdp8 will not be in the same room as the wood dust would not be good for it! but I will need a terminal by the CNC router, I dont want to risk vintage hardware like a vt100, so what common cheap terminal, or computer running a terminal will be suitable to run in such a harsh environment? laptops are out as they would quickly get clogged.

be imaginative, what could I use?
 
The solution that would seem to be the best would be a nettop from about 2000 which would include serial port and everything else needed. Very low power CPU doesn't need the ability to move air as more capable systems would. I just don't know where to get one anymore. If a USB to serial converter cable would work, I would try for a more recent remaindered netbook which costs less than $50.
 
You can get dedicated terminals from up to the early '90s that have no real value but work perfectly fine as terminals. I've got a couple ADDS amber-screen terminals I nabbed when my workplace threw them out in favor of Linux thin clients that still work perfectly fine, along with Wyse and IBM terminals I got from the recycle center. Keep your eye out and see if you can't find any; maybe ask around local businesses. I work for a call center; if there's one in your area that's been around for long enough, they've probably got a whole stash somewhere in the back.
 
A Pi's not worth the trouble; you'd have to get the base unit, an SD card, a USB-to-serial adapter, an HDMI-to-VGA or HDMI-to-DVI adapter, a monitor, mouse, and keyboard. All of that would run you probably more than a used laptop or terminal.
 
commodorejohn said:
A Pi's not worth the trouble; you'd have to get the base unit, an SD card, a USB-to-serial adapter, an HDMI-to-VGA or HDMI-to-DVI adapter, a monitor, mouse, and keyboard. All of that would run you probably more than a used laptop or terminal.
Click to expand...

Depends on what you already have laying around and it has composite out.
 
If you just need a serial terminal, any cheap terminal will work fine.

If you want to get a little retro, and still economical, an Apple IIe with a Super Serial Card and a single disk drive can run ProTerm and will emulate just about any terminal you'd expect to connect to a pdp... And they're incredibly hardy in harsh environments.

Despite what eBay seems to think, you can pick up complete Apple IIe systems for $40-50. Likewise, you can pick up Wyse terminals for about the same in working condition.

The Pi isn't such a bad idea either, just need to add a monitor, keyboard, and a USB serial port. Run minicom in text mode and there you go. For that matter, any "throw away" 486 or better with a serial port will do the same.
 
Most any dumb terminal will work fine in a dusty environment. You may want to get a keyboard skin or wrap the keyboard in cling wrap to keep wood dust out from under the keys. Otherwise, terminals are pretty immune to the environment they're in, I spent a couple three decades on systems with multiple dumb terminals in terrible environments and saw virtually no failures that could be attributed to the surroundings. Lightning, that's another story :)
 
I've made systems for harsh shop environments, so here's my method.


  • Get a metal air-tight cabinet [or make one] and mount a shelf inside and a glass window sealed with RTV as glue at a convenient height. [plex accumulates dust] Last time I needed one of these, I drew it up and my client turned it out in their own shop. I made the electrical modifications and mounted the equipment. Oh yeah... the whole thing on wheels is helpful for the cleaning crew.
  • I prefer to WiFi these shop machines and not take the chance of electrical mishaps getting from the CNC into the shop LAN network. Provide an antenna on the outside [top?] of the cabinet to an access point in the shop office. No floppy or CD/DVD transfers to this PC... everything on the shop WiFi LAN.
  • Next, include a power strip on the inside of the cabinet, with a switch on the outside.
  • For the PC, I'd use any old PC [even a laptop] - the lower the power consumption the better. It must have a serial port [obviously] and USB for keyboard and mouse. Trackball is better for shop - keep it and the keyboard in a plastic bag, but no matter what you do - they'll need to be replaced occasionally.
  • Remoting the PC's power and reset button to the outside of the cabinet is a nice touch.
  • All wires into the cabinet must be air sealed with RTV. [not as easy as it sounds]
  • Some like to pressurize the cabinet with a filter and fan. Not me. I put the filter and fan on the inside of the cabinet just to keep the atmosphere in there clean. Just sitting on the shelf, visible in the window so I can see there's no dust accumulating on the filter.
  • If heat is an issue, paint the cabinet flat black on the outside. This will maximize heat transfer. [black body radiation] If you do this, don't forget the bottom of the cabinet. ;)
  • Windows Hyperterminal works fine for most applications. Sometimes I've written my own terminal emulator in BASIC, but that is not usually needed as Hyperterminal includes pretty good VT100 and VT52 emulation and includes file transfer tools which substitute for paper tape. I recall one machine [a Holzma Panel saw I think...] that wanted programs transferred to it via KERMIT. Go figure.


Where is your PDP-8 going to be housed? Not on the shop floor I hope.
 
From my experience with some of my customers computers as long as you blow out the dust and crud from the psu now and again and the CPU heatsink and fan then the older PC's seem to last quite well in HORRIBLE environments. CDROMs and floopys wont like it however. Id just use " any old " XP system you can find though better if its got a real serial port as the USB to serial convertors are not always very stable, the ones I v tried anyway. As for terminal software, I tried hyperterm but had various problems with it on my 8 so wrote my own in Delphi, its a bit rough and ready but I can mail you a copy if you like.
Dave
 
RSX11M+ said:
I've made systems for harsh shop environments, so here's my method.


  • Get a metal air-tight cabinet [or make one] and mount a shelf inside and a glass window sealed with RTV as glue at a convenient height. [plex accumulates dust] Last time I needed one of these, I drew it up and my client turned it out in their own shop. I made the electrical modifications and mounted the equipment. Oh yeah... the whole thing on wheels is helpful for the cleaning crew.
  • I prefer to WiFi these shop machines and not take the chance of electrical mishaps getting from the CNC into the shop LAN network. Provide an antenna on the outside [top?] of the cabinet to an access point in the shop office. No floppy or CD/DVD transfers to this PC... everything on the shop WiFi LAN.
  • Next, include a power strip on the inside of the cabinet, with a switch on the outside.
  • For the PC, I'd use any old PC [even a laptop] - the lower the power consumption the better. It must have a serial port [obviously] and USB for keyboard and mouse. Trackball is better for shop - keep it and the keyboard in a plastic bag, but no matter what you do - they'll need to be replaced occasionally.
  • Remoting the PC's power and reset button to the outside of the cabinet is a nice touch.
  • All wires into the cabinet must be air sealed with RTV. [not as easy as it sounds]
  • Some like to pressurize the cabinet with a filter and fan. Not me. I put the filter and fan on the inside of the cabinet just to keep the atmosphere in there clean. Just sitting on the shelf, visible in the window so I can see there's no dust accumulating on the filter.
  • If heat is an issue, paint the cabinet flat black on the outside. This will maximize heat transfer. [black body radiation] If you do this, don't forget the bottom of the cabinet. ;)
  • Windows Hyperterminal works fine for most applications. Sometimes I've written my own terminal emulator in BASIC, but that is not usually needed as Hyperterminal includes pretty good VT100 and VT52 emulation and includes file transfer tools which substitute for paper tape. I recall one machine [a Holzma Panel saw I think...] that wanted programs transferred to it via KERMIT. Go figure.


Where is your PDP-8 going to be housed? Not on the shop floor I hope.
Click to expand...

I like this idea, I could put a semi valuable low power computer or terminal in the box, I think maybe something that can take a common ps2 or usb keyboard maybe by using an adapter, and use a silicone skin cover as a keyboard protector as they are cheap and the keyboard can be easily replaced, I also love the idea of putting it on wheels.

and I think for now I will stick with a wired serial link, but I will use optoisolators at both the pdp8 and terminal end.

and dont fear the pdp will not be on the shop floor, it will get its own computer room, with some sort of air filter
 
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I know lots of folks will have different interesting ideas for various vintage tech. I'm not sure what all would be good in that environment specifically though. You could use a small laptop fairly easily on a wheeled cart/table if you want it to get out of the way quickly.

You don't already have some spare gear sitting around dying to become a terminal? I was thinking something like a 3com Audrey might make a fun one or a Netpliance or something. Lightweight/low power systems that have their charm and don't take much space up.

Someone already mentioned I think something palmtop like an Atari Portfolio or an HP LX200 or something. Only problem there is you might misplace it since they're small lol. Hell even a TRS-80 model 100 would do a great job probably for the terminal side of things.

You could probably hack up for relatively cheap some wireless technology to some of them too and have a wireless serial terminal.

One can pretty much go anywhere in the fantasy though. Xybernaut/wearable computer system to access it? :) Hook up a p5 glove to your wearable and freak some people out by starting your cnc with gestures. ;-)
 
I have a lot of old computers that could be used! but want to hear others ideas on how I could do it, I do have a Atari Portfolio!, I have to fix a sticky key but it would make a great pocket terminal for the pdp8! and there are a few ways to make the rs232 link wireless, the PockeTerm is new to me and could work well as I can use a cheap keyboard and I have a stack of small old VGA CRTs, the wireless RS232, and metal air-tight cabinet are great idea I had not thort of! I think I will go more retro, a wearable computer would be cool but not in the CNC workshop, I have some IBM XTs but a dont want to risk them, I do have a clone XT, it has 2X 5.25 disk drives no hard disk and a com port I think? I could fit one of the new ISA to IDE cards and a tiny SSD! and I could use a standard keyboard in XT mode, my Dad has a stack of large 286'S he has no use for that could be fitted with a SSD like the XT? I have a stack of mother boards from XT to P2?
the problem with a laptop is to keep it working it will have to be but in an air-tight cabinet with external keyboard ect, and it will look a bit silly, I have some BBC's and BBC masters, 2 commodore 4032, only one working, a commodore vic 20 and some commodor plus/4 ect. but they have the problem of how to hook up an external keyboard and finding a small color or black and white tv as a monitor is getting hard to find, maybe go barebones and use one of the clone XT mother boards with an ISA VGA card VGA CRT and SSD but take the cases off the monitor and PSU and not case the m/b and but it fitted in the air-tight cabinet, with a safety, to kill the power when opened.
 
I would on a more serious note just use what you have laying around. The older the computer the better since you're just doing serial communications, and older USUALLY needs less cooling. I'd think any clone or even 286 would probably be pretty happy and workshop hardy. Not sure how much dust, etc would affect many of the devices listed, but that's why vintage systems tend to last in warehouses and especially CNC shops :)
 
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