What's inside this old military telephone? | TA-1042 Part 2
ฝัง
- เผยแพร่เมื่อ 13 มิ.ย. 2023
- Curious? Join us on the Discord: / discord
In this episode we cover the hardware of the TA-1042, a digital non-secure voice terminal (DNVT) used by the military in the 90s-00s. We then explain how we can use modern components to create compatible switching equipment, with a bit of EE fun along the way!
To buy this crazy contraption: www.tindie.com/products/nicka...
Episodes in this series:
- part 1: project overview • Reverse Engineering a ...
- part 2: hardware reverse engineering (you are here)
- (upcoming) part 3: programming real time firmware with the Raspberry Pi Pico
- (upcoming) part 4: USB programming and interfacing these with SIP
- (upcoming) Bonus video: the DNVT fax machine
From the extras channel @NicksKnacksExtras
- Video user guide: • Digital Military Telep...
- Soldering/assembly tutorial: • DNVT Switch Assembly I...
More details:
The TA-1042 is a quite slick looking military phone that uses the CVSD audio codec and a proprietary switching protocol. The project implements a hat for the Raspberry Pi Pico (RP2040) cortex M0+ microcontroller that leveraged the Programmable I/O (PIO subsystem) to encode/decode data from differential Manchester encoding provided by the phone.
The entire project is open source! For the full details see the product page: nicksknacks.net/dnvt-switch/
If you want to support our channel and get some fun perks, we are now offering memberships:
/ @nicksknackstech
And no, there's nothing surprising about the circuits. Sorry XD
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Hey all! Thanks so much for watching. Sorry this one took so long but hopefully you’ll see why when you watch it :)
Not sure how it got in there, but a discord message notification sound is audible at 10:27, haha, now imagining running discord through one of these a la one of Valefisk's jokes about his friends' horrible microphone quality.
@@jero37 yeah when I finally heard that I was about 110 hours into this video and decided I didn’t care enough to re-record a fifth time 😂
the long-awaited sequel is finally out! so stoked
Tipling X Knacks collab coming soon?
@@gregpf maybe actually hahah
@@gregpf buckle up for the Nick's Knacks technical explanation of the Mexico City live concert recording :)
I was so glad to see this episode come out. Been waiting for a while to see the follow-up. Very cool project.
I commend you both for your hard work, knowledge, and puzzle solving solving abilities. Very nice job, boys.
yooo, I was just thinking about this project today! nice to see it is still going along and evolving :)
Outstanding video guys! Thanks so much for sharing this! Mad skills!
Really interesting, a lot of effort put into it. When I was in the Swedish armed forces on this side of the millenium. We used a phone made by Ericsson called m/37 and yes, that is 1937. Made of bakelite, completely indestructible.
Wow - amazing content! I love these old phones. Excellent analysis and explanation. I’m not an electronics expert, but I love reverse engineering protocols and this was some excellent sleuthing. Well done!
amazing work, Nick! loving the crayon illustrations haha
Neat channel and thanks for the easy to digest breakdown of everything you guys provided. Keep up the good work!
Excellent work gentlemen, keep up the very entertaining videos.
Super detailed. Great job boys
You’ve really got a knack for this, we need more videos! Best channel on TH-cam, nice work!
the puns are real :) thanks!
This is the first video on your channel that I watched, and it was AMAZINGLY well done! Your technical explanations were masterful - you made it understandable, but also entertaining to sit through the whole thing. What made it worth watching is that you kept referring to the primary subject (TA-1042) and why the tutorial tangent (transformers, for example) was relevant. Keep going with your videos!
Thanks so much! This one took quite a few revisions 😂
I agree, same reaction. The care and effort made for structured content that is fun, informative and inspiring. A rare treat.
@@nicksknackstech I can only imagine. But seriously, the results are absolutely top notch.
@@chromosundrift yeah I’ve been insanely frustrated with the decline of TH-cam content over time with all the channels just churning out sponsorships with half baked videos attached. My crazy theory was that if I made interesting videos like I enjoy, other people would watch them 😂
I truly love what you're doing...
I was enjoying this anyway but then you teased a cursed fax machine. Now you have my full attention.
Why cursed? We were able to get it to transmit through the switch but replaying the data didn't produce any output (it was set to broadcast mode). There is one other guy who has one and we are going to try to run the data over SIP once we get that working in standard full duplex mode.
Thanks for the knowledge. your differential signal walk through really stuck with me
Been waiting ages for this!!!!
I just want you to know that I subscribed to your channel in the first 5 seconds of this video. Keep it up!
was waiting for this, finally here
cheers
one of the best videos I've seen on youtube for some time. content is very interesting and the video is very well made. thanks a lot.
Glad you enjoyed it!
10:00 WOW you managed to explain a concept I never could fully wrap my head around in a matter of minutes! I knew AC and DC could be sent through the same wires simultaneously- I was just confused about how they were separated back out.
Glad you enjoyed! Took a while to put this together :)
A cool project, nicely presented.
Really well done! Thanks!
I am a hardware-hack type of EE and have had four of these phones sitting in a box in the closet for about ten years now. I want to use them on my property for remote locations (90 acres).
Rob did some simulation which suggests the phone and switch can handle about 4km of decent wire before we see too much attenuation but we haven’t tested it ourselves. We are selling these on Tindie along with the adapter boards to use RJ45 between the switch and TA-1042. We have both kits and assembled/tested versions.
Super excited to see the follow-up video, and can't wait for the rest of the series. I don't mind the back to basics EE coverage, but would appreciate a little more detail on the circuits. Maybe a logical trace of the final board following the signal path, that would help bridge the current gap between the low level theory of operation and the system level architecture.
Excited for the next couple episodes! This is really great content for a first series on a channel.
If you just want the circuit the board files and schematics are open source. There isn't much other than what I described here for the phone interface, though there's an expansion header and i2c interface for the display: github.com/rrruark/DNVT/blob/master/PCB/6_switch_V3RT/DNVT_box3rt.pdf
i went to school at Fort Gordon GA in 1998 and part of my course in the army was to learn to operate and maintain these phones. used them for years. soldiers would come to me so they can make phone calls home. it would be kinda kool calling home from one of these out in field.
Great video. You guys are exceptionally smart
You're the man! Great video
I like your well documented equipment, even when some has decided to throw the manual out, there still be a chance to see how it works and how to connect.
I love how the "Auto-Set" button has been removed on the oscilloscope! Great work guys!
The one you just push repeatedly until the scope works properly? 😂
thanks for this awesome video
Well, I can say this: This was really, really random. And I love it. I am subscribing!
The channel is Nick’s Knacks not Nick’s pragmatic education on practical things you’ll find useful long term 😂
The wait is over🥳🥳🥳🥳
Excellent. Random find and a great 42min watching.
Great work .
absolutely brilliant thank you
This is such a good overview of the reverse engineering process. It was very entertaining to watch!
One nuance you may have missed on those protection inductors on the input side is the resonant frequency. The inductors in the phone look more like ferrite beads to me, meaning the composition of the ferrite was carefully selected to give the component a high impedance in a specific frequency range, maximising it's utility as an input protection device. Basically ferrite beads are intentionally lossy as they're meant to be used as filters.
The inductors you used look like power inductors, meaning they're optised for low loss energy conversion applications like buck and boost converters, and they won't give you the same kind of filtering performance the original did.
Alright you’ve nerd sniped Rob and we will be testing the difference 😂
So this is very low bandwidth internet over power line basically.
Great channel. And no. Not basic at all. You are great at explaining this so anyone can understand.
A very complex device.
It turns out I need to go back to engineer school. Life has been hard to me. Great video, great work on the telephony, really fun!
School is overrated, you can just hang out with nerds and debug old gadgets at midnight on a friday evening ;)
@@nicksknackstech good call. Honestly i learned more in my life taking things apart and reverse engineering, but the initial book knowledge is important to remember all the values and maths..
yeah I agree -- I actually found it most helpful when I first did some spelunking of my own, then went back and took a course. For example I had done database work on my own before I took a databases course, and it helped me put everything in context. There are a ton of resources around for learning, and part of my intent with this channel is to provide the same sort of educational content for people looking to do similar projects :)
thanks so much. i already feel a bit cleverer by being bemused at your video. nerdery of the first water. top hole!
I see that this channel would definitely goes "BOOM!"
faster than a rocket ship any time soon...
🤗
As a seattleite myself, there are definitely others fascinated with this older tech, but im just only now learning electronics + circuitry in my 30's, even after being a mechanic for years. Unfortunately RadioShack was a husk of a store by the time i was disassembling things to figure them out for fun. Also, there was no youtube back then, no free courses, and no podcasts😂 thank you for making this video! It scratches my nerd itch, and its still related to what im studying.
Oh fun! Do you do the seattle hardware meetup? Every Thursday :) Send me an email if you’re interested.
@@nicksknackstech I've never heard of it, thank you! I live right on the county line for the greater Seattle metropolitan area. I definitely will send an email, I actually have time for a month to visit. That would be so much more interesting than breadboard and Arduino experiments..
In the 90's I was repairing radios for the Army. The maintenance company I belonged to also included telephone repair techs. I of course saw those phones, but didn't work with them.
They seem to be pretty reliable. Friend who used them in the gulf war said the extent of the maintenance was washing the boards off under water (since they’re all conformal coated).
Thanks!
That phone has such a cool vibe to it
If it didn’t look cool we probably wouldn’t have done the project 😂
This idea wouldn’t be a bad idea for a house intercom given each phone has its own call number you can dial.
Rob, every Bell needs his Watson!
Every Sarah needs her Astrid...
pretty sweet :)
Just a tip taking 2 9v batteries and connecting them positive from one battery to the negative of the other battery is called a series connection
As someone who uses old bulgarian made TAP-77 military phones, this video is fire.
What on earth is that?
love it
nice video
This is so cool! It reminds me of the Tft 96 AWITEL from SIEMENS that is in use in the Swiss army. It is similar in that it is also a non-secure voice terminal, but it doesn't need a switch to work (unless you want to connect to a normal telephone network). What's even cooler is that it connects inductively to the twisted pair, so you don't need to cut any cables. Unfortunately these aren't on eBay like DNVTs, even though they are from the 90s :(
it is quite possible they are still using them :)
@@nicksknackstech Yes, the army is. But they were also sold on the civilian market, so I was counting on that. They didn't make a whole lot though.
There is a wikipedia page in german if someone wants to read on that.
Differential Signaling is used on SATA SSD drives and makes for the use of long cables.
wow, nice ... TIP: often products from China have pads for components (like chips) of different sizes (incl. SMD & blob & maybe even trough hole), to be more flexible on sourcing parts
Parts shortages:
I assemble my own boards - I probably shouldn't because it takes a long time.
It takes me about a year to put a board design like this together once I have a schematic.
All of the "jellybean" parts like resistors and caps are always the same size on all my boards - 0805. This way, I can order bulk when available and they'll work on all my boards. I can see and solder and rework 0805, smaller parts start to get to be a pain in the arse.
With "special" parts, like transformers and level shifting ICs, I closely look at the manufacturer websites to see if the part is marked for discontinuation (not for new designs). I also try to use parts which I know are used over and over in some other product which sells well. This encourages the manufacturer to continue making the part.
Transformers for me are always ETAL branded as they have a pretty common pin spacing.
If there is a problem with a part being available, or is soon to be discontinued, I will quite happily take an axe to my schematic BEFORE I start to lay out the board.
Front panels:
I've started adding a copper-pour to the rear of the panel, and then making the screw-holes with plated through-holes with a large circular pad on the front so that the screws can "connect" to the panel. I also expose the rear perimeter of the panel and sand off any powdercoat from the main enclosure ends so that the panel can "connect" to the enclosure. This makes for a fairly robust continuous chassis enclosure, fully wrapped in equipotential metal. It tends to help with audio gear attached to ultra aggressive digital RF gear and interference.
Clever idea that, using RS432 drivers
you guys are way way way above me, i was a western electric co equipment installer for twenty years before retiring so this is very interesting to me. in an old time telephone office .lol , when you pick up your hand set the central office equipment gives you dial tone and connects you to an incoming register for touch tone -( dial tone multi frequency)to receive all the pulses for the numbers you want and passes them on to a completing marker to complete your call. am i wrong in saying that you are setting these phones up to work with no central office and just connect all of them to one line and have them able to tell if some one is looking to call them and ring the right phone and once the phones connect you can talk with just those two phones. i am probably wrong but i think by using all these codes you are doing away with the central office.please don't laugh , i have trouble with my smart phone. i love all kinds of surplus military electronics equipment . thanks for the videos even if i don't understand all that you are doing.
The device we created has two “modes,” basically if you just give it power it behaves like a line simulator device where you can set up a few POTS phones and call between them. We are working on a VoIP mode which basically uses a computer program called Asterisk to emulate switching equipment, and it can be interfaced with telephone infrastructure via gateways.
We are working on a POTS version with DTMF decoding.
@@nicksknackstech POTS to SIP, be it Asterisk or Kamailo would be very neat.
And then one could set up osmocom-analog and do dumb things, like call from an NMT450 or AMPS phone to the DNVT terminal.
@@2ftg yeah it's been immensely frustrating to try to play with POTS phones and every single ATA has a router and 30,000 random NAT options baked into it. A simple open source 8 line POTS interface with line simulator features and asterisk compatibility would be quite fun, not to mention we think we can get it fully assembled by the PCB manufacturer (as opposed to this unit where I have to solder transformers in my back bedroom, which drives up my effort/cost to sell them).
i used to plug my "botinne" into the phone splicer line in the pole on my ladder and this is really interesting
I bought your switch and ethernet adapters, tons of fun! Any updates on connecting these to a laptop for voip?
Hey sorry for the delay - the plan is to create one pjsip process per line and then register it to an asterisk server or similar. This will transmit the raw CVSD data over SIP to allow data modes, then leverage a CVSD codec in asterisk to allow transcode to other formats like ulaw. Such a project is a new endeavor to me as it requires piping command/control/state plus streaming audio data between two Linux processes which I have yet to perfect. I’ve chatted with some telecom folks and they agree this is probably the best option but it requires essentially demuxing the audio data and distributing it amongst different pjsip processes. I had some help dealing with the pjsip side but any collaboration or emotional support would probably help speed things along. Feel free to email or join discord for more or to help out :)
"Consider the following" 😁 didn't slip past me🤙
😂
@@nicksknackstech was one of my favorite shows from my childhood 🤘😁
VOIP would be great as it would give access to a proper phone.
bloody great. I particularly loved how you explained transformers and so many of the details of the electronics. As a software guy who never studied EE, you probably have no idea how wonderful this is. All packaged around a well-sized reverse-engineering project. Thank you so much!
Quick question: you explain a lot of elementary components and circuits that make the whole but not op amps. You can't explain everything! My question is did you skip op amps because they're tangiential, because they're assumed knowledge, or something else? I would have thought transformers were more basic than op amps, accordingly, less surprising if you had skipped transformers and explained op amps.
I'm curious because my casual, ad hoc EE learning I lack the map that identifies things in orthodox order.
They aren’t really the key interface of this system because they are only used in the phone on the RX side as a comparator (along with some analog audio we didn’t reverse engineer since the switch doesn’t care per se). On our switch we use RS422 drivers instead which no doubt have op amps inside but they are in theory black box. The comparator is not the most interesting use of an op amp either (you can literally just use an op amp as a comparator by connecting to both leads) but I would guess that the need for some level of hystereses makes this circuit a tad more complex on the phone RX side. Probably makes more sense to dive into them when we do the analog phone project.
Balanced audio doesn't actually need to send the signal inverted. It just needs a difference.
Excellent video.
Do you have a link to where to source the case?
I really like how the pcb slides in, & the pcb end caps work. I could see myself copying that on future projects.
I think it’s this one? www.mwrfsource.com/products/1-5-x-2-91-x-4-33-aluminum-box
There’s a link in the GitHub bill of materials
@@nicksknackstech thanks - and sorry I missed the link the BoM :)
They were just beginning to use them as I was coming into the army in 1981. Prior to that, we were using the TA-312
Was it the TA-954? Most of the TA-1042s I see are manufactured 1992-ish.
Man, it's been years since I used one of these. We rarely used these to call people and talk. However, we used the connector on the back to connect to data terminals which essentially allows us to use the phone network as a lan for our systems. You got that working? 🙂 That would be cool.
Yeah we have one of the fax machines which includes the data cable. Still trying to figure out the details there on how that works. I did find one guy with a data terminal but it’s missing the original software. Our intent with the asterisk/SIP integration is to pass the raw CVSD audio/data directly to maintain compatibility with the data features.
I used to maintain TA-312s and SB-3614s. I think we had the TA-1042s also. I can remember we had a digital phone but I don’t remember if we ever got it to work with the switchboard or what. It’s been too long.
The fact you got their shit working is pretty amazing 😂 Good job.
Rob is a good technician: )
😊
Greetings from Ukraine, mate)! Nice video, really like it)!
OK, with VoIP going this might be one of the projects where it is actually justified to set the precedence field from RFC791 to "100 - Flash Override"
So when will you make your own DNVT phone with a Pico?
Or a Pico based POTS DNVT bridge?
Our plan for DNVT to POTS is to make a separate POTS interface and then use asterisk to transcode. So it would likely be something you’d need a RPi in the middle to use in that way. As for creating our own DNVT we’ve been looking into it. The circuits wouldn’t be hard but I have no experience with injection molding or case design. If we did build such a phone it likely would support multiple interfaces (eg we are looking into using the long range single pair Ethernet with power delivery to allow voice and data).
This needs to be a defcon lecture.
Haha I may have missed the deadline but I’ll be there :)
@@nicksknackstech send me an invite pass if and when u do then.
Since part 1, I've been working on drawing out a CAD model for the TA-1042 in Fusion360. The idea being that if you just wanted to have something that looked like it, but was totally different tech (like i want to do), then having CAD models would make 3D printing etc much easier. However, I'm having a lot of issues finding good reference material, and nothing at all with accurate measurements. So...any chance I could convince/beg you to take some good photos of all sides with a ruler sitting in frame somewhere or something? 😁
Want to hop on the discord? Might be able to use the iPhone to scan it in 3D.
@@nicksknackstech That's a great idea. I'll jump over there momentarily!
This video was terrible and I have no idea why I watched the whole thing. Just kidding - you rock! I have no idea why I needed to know about this phone, though kudos to you for thorough explanations throughout. Have a great week!
caps don't "block" dc, the cap just comes up to signal voltage which doesn't change.
Only question is where do you get those old military phones because I been trying to find them online but keep running into things are phones that are far from be military?
Unfortunately after we posted the first video people have bought up all the obvious supply. There are some tips to check army surplus stores but I didn’t have any luck locally. I don’t have a great way to source them other than eBay.
10:26 - Someone's got Discord open... lol
15:37: does this provide EMP protection...? I remember with the avionics we were developing, for EMP it was 1KV at 1ns impulse... remember that an EMP induces a large current and voltage, and this being a military telephone system from what I remember it has to be EMP proof... in our avionics we had special zener diodes that would detect the gamma flash and short the 5 V power rails to ground for the instance of the gamma flash and induced EMP...
Chatted with Rob and he said that likely an indirect lightning strike would have more potential than an EMP, so the protection from those is probably along for the ride so to speak.
@@nicksknackstech if it is designed for MILSPEC it would be required to have EMP protection… the difference would be the rise times for protection. Lightning protection would be typically, one kilovolt rise time in one microsecond, whereas EMP is one kilovolt rise time in 1 ns. … Try and find the contract under which these were manufactured and the requirement specifications as it will be stated there.
Could you not have the ones and naughts select different tones like a TELEX system.
cool
What you described was differential audio, not balanced audio. Differential audio has two inverted lines biased against a common neutral; whereas balanced audio both lines are 180 degrees from each other independent of the ground or shield line. An XLR connector is balanced audio where the shield / ground line has no electrical relationship to the signal lines and is just there to provide protection from EM interference.
another processor that might work alright is the ESP32, ..and they have onboard bluetooth and wifi, though that probably won't work too well with the aluminum cases. They're dual core 32 bit so they should do some decent processing over and above what the STM32's could do
The issue is that the differential Manchester decode/encode would have to be interrupt driven. Doable but more confusing than a dedicated PIO implementation. In this case even this processor was overpowered for just shuffling the bits to USB, but at $5 can’t complain :)
@@nicksknackstech I don't know if you follow Dave's garage, but he does some pretty complex FFT and sound processing with his ESP32 projects.. I could definitely see the STM32's being overworked unless you're a coding genius and have a lot of experience on getting the most out of small processors
There’s no codec implementation in this version but I think it would be doable for a single channel. It would be a lot easier with floating point/M4 instead of M0+ we have here
Did you dad work for Philips inventing the Digital Compact Cassette system which used the CVSD ADC chips and CVSD DAC chips.
Does DCC use CVSD? I've only seen it applied in lower fidelity phone applications as well as simpler two way radio digital standards. Most of my dad's work was on LPC and its application in encrypted military phones like the STU-II designed for low bandwidth high bit error rate communications.
@@nicksknackstech CVSD or better known as BITSTREAM.
Is it like SPDIF.
For maximum military look-and-feel, the software should be written in Ada.
I have minimal electronics knowledge. And no interest in military phones. I have, however, just watched this entire video.👍😀
Did it make sense? :)
@@nicksknackstech weirdly, yes.😀👍
It worked almost 1/2 the time
if a transformer has 127 V- AC -60 Hz on the primary side. and on the secondary ,a rectifier and a filter cap to smooth the AC ripple , is it still 60 Hz after filtering?
Yeah the frequency doesn’t change. The ripple will still be 60Hz and the size of the ripple is a function of the energy storage capacity post rectifier and the load on the circuit. There are some other tricks people can play to further smooth the voltage like zener diodes. These days though they typically use switch mode power supplies, which have the further advantage that a technique called active power factor correction can be used to improve the power factor of these supplies (ordinary rectifier circuits only draw current when the AC voltage is near max/min) but with active power factor correction circuitry is employed to modulate the current in sync with the voltage waveform.
@@nicksknackstech Hey Thanks Man 😀
A beautiful and extremely well made device. Who would have thought it'd be so advanced? That crazy Aussie bloke would be all over it drooling out of excitement :). Impressive reverse engineering work. That's definitely gonna be a cool project.
Not half bad for a “final assembly in Nick’s back bedroom,” right? 😂
Cool video. Btw, are you participating in endmyopia? Or is someone impersonating you? Just curious.
Haha yeah I do! Not sure I’m cool enough to have impersonators yet. I was gonna do a video on it but probably on a separate Nick’s Rants channel. Down from -4.5 to -1.5 (which is also why my glasses switch frequently if I have to read the prompter 😂).
@@nicksknackstechfor real? 😂 i joined like 1.5month ago the FB group. I've seen your videos before and remembered your name when I saw it on there.
Legit thought maybe it's bs pseudoscience group that uses bots or smth. Do you have discord and would have time to chat? I'm really curious now whether this truly works and would just like to hear your experience with it 😅
I literally used to have a meme prescription of -0.5 that turned to -1.5 and gave me massive headaches. Then every time I went to opto, they just kept loading me with exact same headaches. I wonder maybe I'm just accustomed to it now? Because what I noticed when I started to question these prescriptions, after walking without any correction I am able to see digital clocks from 5-7 meters distances. Able to see house numbers 10+ meters away after blinking. And I'm currently like -7.5. at that diopter range, there is no way I could be experiencing something like that. Was told by opto: you are just imagining things. 😂
Oh yeah shoot me an email through the channel page.
#600 like keep it up
17:13 military cares about EMP from nukes too.
I asked Rob and he said that likely an indirect lightning strike next to the field wire would produce a greater potential pulse, so the EMP hardening likely just came along for the ride with lightning specs.
Once I acquired a military phone, it was black and it had a 4,5 Volts battery compartment. There was also a crank for if you wanted to speak to the ministry of war or the chief of staffs. Not many had a telephone on their desk. It had to be connected with cable, steel wire, cheap wire. it always curled up, never stay hidden. It was good we were never invaded by the Russians, they could have easily trips over the steel cable and broke their necks.
Just like now, they invade a country, they almost drown, get disappointed and want to leave, start making war amongst themselves. You can't win a war with the Russians.
Increase saturation a bit. Show the device only while you talk about it and move the teleprompter closer to the camera.
Grading is not my specialty 😂 though the teleprompter is pretty close to the camera. The lens almost hits it lol.
Transformers. What are transformers Why, we all know, they’re more than meets the eye.
Ah yes, Maxwell’s equation, the perfect toughness on the skin and the ideal amount of grilled onion on my Polish sausage.
That’s about what I remember from E&M physics 😂
Tindy correction: it's 'a USB', not 'an USB' ;)
Yeah but does it have tetris
I totally have almost bought one on ebay just to take it apart; And now their not for sale anymore. 300 USD plus - I remember them costing 25 usd
Yeahhhh the price has quadrupled since the original video unfortunately. I suspect that the availability has gone down after they were decommissioned around 2008.
@@nicksknackstech I feel like in the future nerds like yourself could make a buck flipping such units and helping out the community at the same time
I’ve asked around but there aren’t very many that have them at the moment. Somewhere there must be a pallet hanging around but it’s probably in a dark corner. We were debating making a clone of these phones (probably not just DNVT and supporting other communication methods like long range single pair Ethernet).
@@nicksknackstech I would not do that. They will work themselfs out of inventories like the old Geiger Counters. We all know Uncle Sam buys bulk
Great, any chance to do same for Washing machines- to improve functionality-of these He ( high efficiency) terrible systems ,
Burn it and buy an 80s model with the real agitator. If you're stuck with them, clean out the stupid rubber ring frequently and you can use vinegar during the colors cycle to keep the mold smell down. For whites always use hot with bleach.