Netronics Keyboard Restoration
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- เผยแพร่เมื่อ 2 ก.ค. 2021
- Recently I scored (what I thought was) two Netronics keyboards - one a plain jane ASCII keyboard, the other one of Netronics' coveted keyboard/serial terminal combos. These keyboards are very popular with a select group of collectors, especially those who favour the COSMAC ELF.
These were in slightly rough shape, so in this video I clean up the terminal unit a bit, make some minor repairs and fire it up!
Fastvid Assembly Guide: drive.google.com/file/d/17T8O...
Fastvid Parts Layout: drive.google.com/file/d/11u9D...
Fastvid Schematic: drive.google.com/file/d/119Bq...
Fastvid Char ROM (left side): drive.google.com/file/d/1Cj6N...
Fastvid Char ROM (right side): drive.google.com/file/d/1-vRt... - วิทยาศาสตร์และเทคโนโลยี
It's been a while! My day job keeps me pretty busy these days, and repair videos do take a little longer.
I got a free cell upgrade so I'll now have two cameras capable of 4k 60fps, for multiple angle shots! Excited about that!
And apologies for the 'breaths' you might be hearing.. I suffer from hiatal hernia and reflux. Makes long narration a chore as I can only get out short sentences before gasping for air. Age sucks!
Don't worry, your content is very unique, and in my opinion this should cut you all the slack you need on the presentation side. Thanks for your time and efforts!
Might talk to the kind folks at Deskthority... they have a whole Wiki on keyboards and keyswitches, I bet they can help.
@Tech Time Traveller *RTFM* LOL When I switched from Windows to Linux in about 1998, one had to read manual-pages READ-ME files and the like. if one went to Usenet-News Groups dealing with certain Software or Hard-ware Topics to get some answers to a simple question and if one revealed oneself as a newbie the most often response was *RTFM* , for a long time I did not get that the "F" stood for "Fine" and thought it meant something else.
@@isallah1kafir196 I'm afraid someone has had quite a chuckle at your expense...
The word to use for F isn't Fine, although any given four-letter word of similar capacity will substitute for the correct one.
For some sad reason, we have many people here in the United States who are unshakably convinced that the precise moment one turns 18 and thus becomes an adult, a remarkable transformation of brain chemistry takes place, before which, even so much as _hearing_ certain words will do horrible things to one's life later on. It really is quite silly, when you think about it, but there are enough of such believers, and enough in prominent positions, that we have to use a 'beep' noise over those words during eg daytime television programming.
I'm afraid the F in that particular acronym is one such word, and TH-cam will get remarkably angry at me for using it... but there are plenty of places on the internet which will help you if you ask.
@@laserhawk64 I was of the opinion that the "F" word meant what you imply here. But one day I read one comment (not directed at me) in which the older & wise User told the newbe to *Read the **_Fine_** Manual* this made a lot of sense, since using insulting language was frowned upon in these Discussion Groups.
I'd put that one with the label on display, would be funny to see how many can resist lol
As soon as people see that label: "ooh...touch touch touch!" 😂
Nice video
You have expensive tastes in retro gear. Those eBay auctions for netronics gear are incredibly competitive. Good job getting that keyboard working again.
I just found one on the trash. What do you think it’s worth?
I know this video is almost 2 months old and I just discovered your channel, but I wanted to give you a tip: some early TI-99/4A computers used the same key switches. My TI-99/4A has the same switches in it. The last time I looked recently at the prices of that machine were fairly cheap on Ebay.
some apple ][ systems too.
rom data probably starts at space; if control characters aren't displayed, they don't need data.
That sounds sensible. 32 x 8 bytes is 256 bytes.
Someone probably already wrote in comments but that keypad on top is the lower part of a Commodore SR-1800. One of the best looking Commodore calculators from 1976 :) Great channel!
It's great how you always have such unusual and rare devices in your videos! I had never even heard of most of the computers you show on your channel. Keep up the good work!
My guess the data in the EPROM starts at 0x100 because of ASCII, the first "printable" character (space) has ASCII value 32, assuming 8 bytes / char, it must be at offset 256, 0x100 in hex. No idea about the "gfx ROM" though.
I am thrilled that you are back.
When you get the chance, please let us know about the other keyboard. I realize that there is not much to say without whatever it was attached to, but I am curious about the "calculator" addition. I'm guessing that it serves as function keys -- e.g. the 1 key sends Ctrl-A. It should be possible to determine that from the wiring harness. There is probably not enough content there for a full video; maybe sometime do a follow-up on the state of previous projects.
I enjoy your videos very much - knowledgable, calming, funny and very detailed. I just love how these Netronics units look, too.
PS: Hoping the part at 21:00 about the fan in the Explorer 85 being 12v was just a slip of the tongue - it looks like a mains shaded pole motor to me, so please poke it gingerly. :)
these keyswitches are a pain to clean, they're sealed so they're difficult to open. the 2 round pins are actually screwed in and can be unscrewed if you grab them with pliers and twist. Luckily even if you cut them open after removing the 2 screw off legs it is hard to do enough damage to effect function once reassembled. I have a bunch that I could offer but mine have an angled slider and not a straight one so they wouldn't really work as drop in replacements for your machine unfortunately and you would still need to do some amount of cutting to get them open.
The keyswitches are also made by futaba, not stackpole. The keyswitches in the george risk board are also futaba funny enough, the contact assembly in them is the exact same as the ones in your Netronics board so you could still use them for parts if you were inclined (the slider is also the same between the switches, in case you ever have one that is broken off) Like the Netronics switches the pins of the george risk keyswitches can be unscrewed with a pair of pliers but they aren't glued together so they open very easy. I have no idea why futaba would screw a switch together and still feel the need to glue it closed as well but here we are.
I was going to say the look like Futaba and you can unscrew the legs.
Would love to see some videos on your channel regarding test equipment. Oscilloscopes, multimeters, stuff like that…
seems like it would be a lot of fun since you enjoy these old computers. Some of the beautiful HP and Tektronix equipment from the golden age… Holy crap you open it up and it’s just like a work of art inside.
Would be awesome if you had some test gear videos
There looks to be enough of a gap around the key steam than you could spray in a contact cleaner (Deoxit, Electrosol, Safety Wash II, or even just isopropanol) to get at the contacts, then press the key a bunch then let it evaporate out. I had good luck with this method to clean the Datanetics switches in an Apple ][+ I bought, using MG Safety Wash II since I didn't want to leave the slight residue that Deoxit leaves in the switches
If you happen to be in Calgary or Saskatoon B&E Electronics carriers Deoxit for $28 a bottle, or they'll ship it UPS ground. I'm sure there's a more local electronics supplier that you can find it at.
Yes I sort of employed the Apple II keyswitch tactic.. really doused it with iso and then worked the heck out of the plunger.. but yeah.. didn't improve any. I think the degree of rust may indeed call for something stronger.
I have seen those keyboard models in person, many many years ago. I can just not remember in what context.
Great video! I have a an Elf II.
I have an ELF II, a Quest ELF (the first one, not the super ELF), an original ELF, an RCA VIP and an 1801 Microtutor. They are among my favorites to play with.
I have a very similar terminal, albeit one marketed towards the HAM community, specifically for RTTY. The case is very similar, albeit being a grayish white powder coat, with the rear and underside being blue. From what I've read they even used the same keyswitches. If you're interested in comparing the 2 units i could shoot pictures of it your way.
That would be awesome! Feel free to send those to brad (at) techtimetraveller.com
@@TechTimeTraveller Email sent, let me know if it didn't go through
CRC contact cleaner is also very good, has the little tiny bit of oil in it like deox it and least around here can be found in any big box home store
you can always use a DC supply with an AC input. You don't even have to worry about polarity!
the -12V also goes to the collector of Q2 through a resistor to provide the negative voltage swing for the RS232 transmit line.
So you can derive -12VDC from -8 to -10VAC?
@@TechTimeTraveller No, the -16V is regulated down to -12V via a resistor and zener diode (cr1) which then appears across C2 (see the lower right of the schematic in the dotted outline). This -12V is picked up a various points across the schematic. One place is at R8 on the collector of Q2 for the RS232 transmit signal, and the other place is at pin 9 of the keyboard connector. My guess is it might work better if you supplied that -16V too, more for the keyboard than the RS232. As far as I can see, that is the only way the keyboard will get it's -12V.
Wow, nice Netronics collection! Unfortunately all I have currently is an AP-1 PSU. I've been thinking of getting some sheet metal blanks and bending my own ELF II and keyboard cases. Funny is that famous Netronics blue color is....."IBM Blue" ;)
Thank you for sharing. Greetings from Karachi, Pakistan.
13:55 you can just plug a DC supply, with any polarity, you don't necessarily need an ac supply, you have regulation via 7805 with internal rectification, unless it's using 60hz ac for timing which I don't think so
You got the time travel part right..
Take the key switches and put then in a tube in deoxit.
if you can put them in a container and pull a vacuum on it
Whe the vac is released it will pull the deoxit down the stem and in to the switch.
I cannot bear not knowing what's under that tape.
Memories...
Pro-tip: water, then spit on q-tips, then diluted alcohol. You don't want to take anything off now & the spit pass will act as an enzyme cleaner.
I'd suggest taking the dodgy keyswitches and just immersing them in 99% isopropanol, agitate and remove and clean. The keyswitch isn't airtight.
I tried a variation of that approach dousing them pretty good with 99% iso but didn't seem to get anywhere. I'll try fully immersing them. Thanks for the tip!
@@TechTimeTraveller Immerse them and work the plunger a bunch to get the bubbles out.
@@TechTimeTraveller an ultrasonic cleaner might help as well.
I would buy a cheap sonic cleaner and try it that way.
@@lelandclayton5462 As it turns out, I have a commercial sonic cleaner from my old ink jet refilling business. Thanks for this idea guys! Totally forgot about that.
if u want deoxit check if u have a store called long and mcquade in your town they mostly sell musical stuff but they carry deoxit to.
Ooh.. we do have a few of those. I will definitely check that out! Thanks for the tip!
@@TechTimeTraveller it def isn't cheap at $35 bucks a can though. another good option is nutrol by mg chemicals a Canadian company u can normally find that stuff for about $15-25 a can depending were u look
@@mraaron1584 Looks like they have it in stock nearby.. just trying to figure out which one to go for.. looks like they have Gold, contact cleaner... bunch of different deoxits
@@TechTimeTraveller D5 is good. the gold stuff is just fancy stuff to mark up the price more lol. the d100 i believe that is like a more concentrated formula comes in a dropper bottle and the d5 is the spray.
Are you still looking for some replacement keyswitches?
I think I have some spares.
those keys look a lot like cherry mx keys, you may be able to setup a conversion.
I think whoever printed that DYMO label was fooling themselves. A more honest label might read "THIS IS MY TOY ... DO NOT TOUCH" Unless they actually used it for something serious like industrial process control, but then, who's going to allow random button pushing in that setting?
Shouldn't those EPROM windows be covered as protection to UV exposure?
I'm not too worried. I've had literally dozens and dozens of old machines and nobody seemed to bother covering the windows. They spend most of their time in the darkness of the case anyway.
Why not take one of the SHIFT key switches and use it as the CTRL key????
Because both shift keys are dead too. 😀
21:11 How dare you not to bolt those regulators to the board ? :D
Why do people sell items caked in filth? Back in the 1990s, I would buy and resell vintage video game consoles. I would take everything apart and give the case a good wash to remove the accumulated dust, dirt, etc. It only took a few minutes to make something look so much better.
Yeah I don't quite get it either. It may come down to fear of damaging something.. or they just don't care and want it gone quickly. Saves me a few bucks anyway. :)
Come on man you can't scrap some headphones? Also, a q-tip of vinegar will de-rust the case. I'd take the case to home Depot & get a color- matched custom touchup pen from a color sample of the inner undamaged paint
This is not a toy!
Those key switches look like they may....... be ones where the pins unscrew from the plastic body. You clean them then screw them back in again. See th-cam.com/video/yrBtur6skps/w-d-xo.html
AArrrghh!!!! Use a proper IC removal tool!!!!!!
Usually I do, but sometimes they get so stuck that you pull and the tool either breaks or chips things. I sometimes find it best to just use a little screwdriver to pry a bit. Depends how rusted things are.