I've been looking everywhere for my vintage Chinon Camera - Don't know what I did with it. I should check the fridge again... sometimes I find it in there. Come to think of it, my novelty Liberty Bell is missing too.... gotta check that Fridge.
Fran, learnelectronics, and you take up 90% of my free time. You guys are all different but I respect you all the same. Never fail to learn something new. Dave, I'm saving up to get one of your meters after the holidays. Hope everyone has a great and safe end to a great year.
Nowadays i´m at medicine school here in Brazil, but the love for eletronics should never die!! Always an amazing way to pass the time and learn some new stuff!! Thank you for the channel, Dave!! Keep up the amazing work! :D
My grandfather had a small plane in the 70s and I remember him telling me the autopilot worked by tuning it to a radio station in the area you were headed, and it would home in on the signal
+KingNast I think that the navigation part is fine with that. Flight managment computers list and track the beacons on terrain as the planes passes by, each beacon is tunned to a certain freq. But the autopilot thing also controls the plane to altitude and speed so you dont have to do all the time. By early 70 comercial ariliners were equiped with complex auto pilot systems, even with autolanding capabilities.
Nice to see some avionics kit teardowns, brings back memories from the AF days... wish I could send you some of the stuff I used to work on, worked on F-18's and Bell 412 helicopters for a number of years
I used an Inmarsat ISDN phone in the '90s, and always wondered what kind of antenna it had. It was pretty impressive to get 128Kbit over satellite when most people were still using 56Kbit modems. Thanks for sharing that.
+Markus Birth (mbirth) I mean, there's not too much that'd be terribly interesting I would think. Loran is largely discontinued, the gps is a text screen, and you'd need to set up sample gyro signals to see what the autopilot does.
+Andy Plater I agree. I have also a LORAN-C receiver for demonstration but never used it in flight. Even large airplanes rely on GPS. And if GPS fails they have mostly 3 inertial navigation system running. Anyway there are still other ways to navigate such as VOR and NDB.
FXP1688 I was thinking about that the other day, and how VOR/NDB are getting phased out and what happens to IFR traffic if the gps system goes down, I forgot airliners have IMUs as a backup.
+Andy Plater I had an old II Morrow Loran-C like this... The adjustments for Lat/Lon were the plus / minus keys, and the speed of adjustment was logarithmic based (i.e. the longer the keys were pressed, the faster the degree change.) If you weren't paying attention, you could overshoot your desired lat and wind up at the North pole in just a few seconds!
At 9:35, gosh I love 80's circuit board construction. Look at those passives. None of this SMD 0603 rubbish. Proper through-hole bypass caps, thank you very much.
VERY nice video, Dave. That flight gear was amazing! Please do some tests on it. You said that it could be interesting to play around with serial data from JRC receiver board. That would be something, I'm very interested to see it! Thanks Martin to sending it to the best place in the Planet :)
II Morrow Inc. was a pioneering manufacturer of navigation receivers for aircraft and marine use. They were the first company to introduce LORAN to aviation, and were eventually bought up by UPS, who later sold the business to Garmin.
Hey Dave Thrane & Thrane still exist I am living very nearby in "Kongens Lyngby", they have a lot of antennas on their roof. They are now part of "Cobham Satcom" and they do communication stuff for aviation and more.
The aircraft navigation receivers align with the direction beacon 90 degrees out of phase or "null". The direction accuracy is much more sensitive in "null" than in optimum reception angle of the antenna.
DSP ICs are usually used when people want to do a Fourier analysis. A Fourier analysis allows a signal to be view in the frequency domain instead of the time domain. Placing a signal in the frequency domain allows you to calculate the frequencies that a particular signal is using. I would imagines rather useful for satellite phones and GPS.
LORAN transmitters were shut down in the US in 2010, so that aircraft receiver is officially a paperweight. Might still be able to use it in Europe, in the few places that still maintain LORAN stations.
I'm Danish and I've never heard of Thrane & Thrane but I looked them up and they are apparently still a thing. Mostly they do stuff for our military it seems.
+Nukle0n I worked at T&T 6 years ago with software for BGAN terminals - Explorer and Sailor (they also have Aviator for avian satcom). T&T has been bought by Cobham (UK) so T&T is no more, but they still have head office in Lyngby Denmark - it has just changed name.
I've used PC keyboards with this style of curved-in keys in the 90s. I think it was Fujitsu-Siemens that made them (or before, Siemens Nixdorf, I'm not sure about that, could have been them as well). They always felt a bit spongey, but I found that I could type on them surprisingly fast!
26:41 wow, that bag made it everywhere, ages ago i used to have that bag or one almost identical that i used for the first two laptops i bought myself, and i am practically on the other side of the planet from you (kansas).
Great video as always, some very interesting gear. Just a heads-up, I noticed the red Maxell battery in the Apollo GPS - if you decide to hang onto it you might want to pull that out - Apple used them back in the mid 90's and a lot of them are starting to explode, taking out the Mac's logic board (and any other parts around the battery) with them.
I've actually flown an old Cessna 182, way back, that had the same autopilot in it. It's a single-axis (bank), so you have to still manually control the pitch. I remember going to a 2-axis autopilot, being a huge deal. I started flying in 1999, so I never even had to learn LORAN. VORs and DME made those obsolete. And, now GPS is making those obsolete. So, LORAN was obsoleted by tech that is already obsolete...
That GPS receiver may actually have a higher update rate than modern versions, which are restricted by the military. I think they might have introduced this after selective availability was turned off. For a while all you could get was 4hz, but I've seen more recent chips that were 10hz.
II Morrow were bought by UPS Aviation Technologies (yes that UPS), and added to their 'Apollo' line, which was then bought by Garmin. If you think the avionics look old, wait until you see a Lycoming O320 engine, still sparked by twin magnetos. I remember flying once with $30k worth of nav radios in the panel and we were using a ($100) yellow etrex on a flexi gooseneck suction cup'd to the windscreen; because it was a lot easier.
The adjustments at 14:28 are: (supposedly to adjust the various op-amp gains and nulls) HDG Gain = Heading Gain HDG Null = Heading Null NAV 1 Null = Navigation input source #1 null NAV 2 Null = Navigation input source #2 null NAV Integrator Null = The nav intercept null (my best guess) It can be annoying flying with one of these things that is not adjusted correctly. Sometimes the aircraft altitude or heading will oscillate under autopilot control while it is "hunting" for the position it wants.
Alright Mr. "OutaTime" At 28:48, do you see the traces in the center of the antenna? does it not resemble a flux capacitor? I guess it was unpopulated, so you know what that means. it wasnt the special edition.
+Power Max He probably keeps them private until youtube has rendered the 1050p resolution as well. Otherwise people are gonna complain about the resolution, because most don't understand how yt works. You never win.
+captian k'Lang Dear captian k'Lang I want to express my sincerest apologies for my failure to check for typos. I realise that my oversight was totally inexcusable and disrespectful. I can only imagine the distress I have caused to everyone and the damage that it has done to your trust in me. Yours sincerely, Jack White
Great stuff! Love the avionics and GSM phone . . . *Big* thumbs up! Good to see something from a different industry for a change (not to mention I'm a pretty huge aviation fan) . . . . I don't think LORAN is used for anything at all today . . . FYI it operated at very low frequencies, around 1.8 MHz just above the US AM broadcast band.
another awesome video! You've got to come up with some other way of showing a close-up of the mailbag items. Holding it, out of focus, close to the camera Stinks. We need these details Dave! Thumbs up here.
Please return to this mailbag format in the future too! Otherwise lately I have to skip forward all the time to find the 2 minutes out of a 40 min video that actualy have some electronics. I love your long videos but I love them much more when they are about electronics!
I got one of those old Speccies for ONE POUND back in the early 90s! Primary school "jumble sale" find... There was a note attached to it which said "there is a fault with this item but we do not know what". No idea what kind of fault they were referring to but it seemed to work fine until I got bored and went back to the C64 :D
There is a german Bundesadler on the Case of the GPS and some sort of american certification. Do other countries not require a certification for flight gear?
"Welcome to everybody's favorite segment, FAILBAG!" Just kidding, but every time he says mailbag I can't help but think "failbag". I have no life. "I love a big package!"
Dave, I recall Fran sending you some nixie tubes for you to do a project. Is it something you might consider do, for example a bedside clock? It would be nice! Nixies are AWESOME! Greetings from Portugal!
Get Dave2 to focus pull and if he doesn't want to do that (wouldn't blame the guy) have him create one that works by foot pedal for you to use when waving items for closeups!
Loran system wasn't popular in civilian aviation, VOR/DME system is the more popular, VOR stand for "VHF omnidirectional range" and DME stand for distance measuring equipment.
If i received like this parcel like this, i will feel exciting exactly as your feeling. But I will deep study the purpose why the engineers design that ways.
+TheChipmunk2008 Nifty, but what's the advantage? Maybe I'm not imaginative enough, since I don't understand why you would want to hook a satellite phone into a landline and not just use the handset built in to the sat phone. Even for emergency backup comms at a remote facility, I would think the portability would be more important in case of evacuating the building (fire, etc).
+zrobotics Not honestly sure, maybe to allow equipment that expects a landline to use that instead in an emergency? For the price they charge(d) for those phones, adding the functionality wouldn't have been difficult
+Mikael Pedersen It was likely also done to allow connection of a dialup modem since there were no obvious serial ports for computer data. Satellite phones were/are often used in locations with no communications infrastructure, so the ability to transmit field data back to home base was often desirable despite the high per minute charge of satellite.
I've been looking everywhere for my vintage Chinon Camera - Don't know what I did with it. I should check the fridge again... sometimes I find it in there. Come to think of it, my novelty Liberty Bell is missing too.... gotta check that Fridge.
the fridge is where I always find my tv remote when it goes missing
I love seeing the old stuff.It's a work of art.All hand solder.All hand done. Even the PCB traces.I miss manufacturing.
Thanks Dave.
I like this format a lot more. Reminds me of how it used to be. Mailbag and teardowns. Love it =)
+Christian Ivarsson I agree. I love this old school mailbag style.
Fran, learnelectronics, and you take up 90% of my free time. You guys are all different but I respect you all the same. Never fail to learn something new. Dave, I'm saving up to get one of your meters after the holidays. Hope everyone has a great and safe end to a great year.
Nowadays i´m at medicine school here in Brazil, but the love for eletronics should never die!!
Always an amazing way to pass the time and learn some new stuff!!
Thank you for the channel, Dave!!
Keep up the amazing work! :D
Must say, one of the better mailbags... cool gear we looked at!
My grandfather had a small plane in the 70s and I remember him telling me the autopilot worked by tuning it to a radio station in the area you were headed, and it would home in on the signal
+KingNast I think that the navigation part is fine with that. Flight managment computers list and track the beacons on terrain as the planes passes by, each beacon is tunned to a certain freq. But the autopilot thing also controls the plane to altitude and speed so you dont have to do all the time. By early 70 comercial ariliners were equiped with complex auto pilot systems, even with autolanding capabilities.
I hate it when electronic components have DO NOT EAT label on them. I'll eat whatever I want, you can't control me!
+John Grammaticus I wish they would just recommend a wine to go with it and save time.
+mwildish I like a nice Ferranti with my mailbag.
+John Grammaticus
The anti authoritarian in me can't stand it either.
It's taunting me.
Nice to see some avionics kit teardowns, brings back memories from the AF days... wish I could send you some of the stuff I used to work on, worked on F-18's and Bell 412 helicopters for a number of years
"Thrane & Thrane .. sounds like a bunch of lawyers" I laughed way too hard.
The c150 I learned to fly in had that exact Loran in it. Brings me back.
Lol, the visual effect when you're pointing that Crocodile Dundee knife at the camera! It actually made me dodge the screen.
Thanks for doing mailbag dave, we know it takes a lot more work than it looks.
My favorite type of mailbag.
I used an Inmarsat ISDN phone in the '90s, and always wondered what kind of antenna it had. It was pretty impressive to get 128Kbit over satellite when most people were still using 56Kbit modems. Thanks for sharing that.
awesome to see inside this old flying gear
+Andy Plater I hoped he'd try to power them on though.
+Markus Birth (mbirth) I mean, there's not too much that'd be terribly interesting I would think. Loran is largely discontinued, the gps is a text screen, and you'd need to set up sample gyro signals to see what the autopilot does.
+Andy Plater I agree. I have also a LORAN-C receiver for demonstration but never used it in flight. Even large airplanes rely on GPS. And if GPS fails they have mostly 3 inertial navigation system running. Anyway there are still other ways to navigate such as VOR and NDB.
FXP1688 I was thinking about that the other day, and how VOR/NDB are getting phased out and what happens to IFR traffic if the gps system goes down, I forgot airliners have IMUs as a backup.
+Andy Plater I had an old II Morrow Loran-C like this... The adjustments for Lat/Lon were the plus / minus keys, and the speed of adjustment was logarithmic based (i.e. the longer the keys were pressed, the faster the degree change.) If you weren't paying attention, you could overshoot your desired lat and wind up at the North pole in just a few seconds!
At 9:35, gosh I love 80's circuit board construction. Look at those passives. None of this SMD 0603 rubbish. Proper through-hole bypass caps, thank you very much.
I wish David would do these mailbags with you. It would be a nice combination of cute and rugged Australian manliness.
VERY nice video, Dave. That flight gear was amazing! Please do some tests on it. You said that it could be interesting to play around with serial data from JRC receiver board. That would be something, I'm very interested to see it! Thanks Martin to sending it to the best place in the Planet :)
It was great to see those old 555's.
Just gotta love those old microwave phones, they'll cook your take out while using the phone! Multitasking FTW!
The "idiot" is called Rick Dickinson. I quite like the QL/Spectrum+ style keyboard, the downside is how wobbly the keys are.
+ZXGuesser I-still-have-my-ZXSpeccy128-in-it's-original-box-along-with-a-seperate-twin-floppy-disc-drive,-that-was-specially-custom-designed-for-this-computer.(also-still-in-it's-original-box).
I-learned-how-to-touch-type-on-this,...Such-a-long-time-ago!
@@stationplaza4631 do you not have a space key on your keyboard?
II Morrow Inc. was a pioneering manufacturer of navigation receivers for aircraft and marine use. They were the first company to introduce LORAN to aviation, and were eventually bought up by UPS, who later sold the business to Garmin.
Looks like a circularly polarized patch antenna array ... the 2 parts of the antennas (pushing it 90* out of phase) give it circular polarization
+Alyx BioHaz Could even be a phased array!
The best bit was the optimism of sending something to the mailbag by Express Post. I wonder how long it sat on the shelf for...
Tear open Tuesday Dave? Love it.
I'm always fascinated by the RF voodoo. Are there any guides on how to interpret the runes or is that all secret squirrel stuff?
+Rob Nelson Look up Distributed Element Filter design
Look up The Signal Path channel, he's an RE engeneer and has a Lot of tutorial on his channel!
+Rob Nelson
is this a squirrel girl reference ?
+Fiercesoulking There's a 90's cartoon called Secret Squirrel.
That was a great one! Thanks Dave!
Hey Dave Thrane & Thrane still exist I am living very nearby in "Kongens Lyngby", they have a lot of antennas on their roof. They are now part of "Cobham Satcom" and they do communication stuff for aviation and more.
The Loran-receiver would make a nice clock for the shelf in the lab!
The aircraft navigation receivers align with the direction beacon 90 degrees out of phase or "null". The direction accuracy is much more sensitive in "null" than in optimum reception angle of the antenna.
DSP ICs are usually used when people want to do a Fourier analysis. A Fourier analysis allows a signal to be view in the frequency domain instead of the time domain. Placing a signal in the frequency domain allows you to calculate the frequencies that a particular signal is using. I would imagines rather useful for satellite phones and GPS.
LORAN transmitters were shut down in the US in 2010, so that aircraft receiver is officially a paperweight. Might still be able to use it in Europe, in the few places that still maintain LORAN stations.
28:56 shouldn't it be LHCP or Right Hand Circular Polarised?
+Fabian Neundorf Yep. I'm an idiot.
+EEVblog Glad we got that established 8-)
I'm Danish and I've never heard of Thrane & Thrane but I looked them up and they are apparently still a thing. Mostly they do stuff for our military it seems.
+Nukle0n I worked at T&T 6 years ago with software for BGAN terminals - Explorer and Sailor (they also have Aviator for avian satcom).
T&T has been bought by Cobham (UK) so T&T is no more, but they still have head office in Lyngby Denmark - it has just changed name.
I've used PC keyboards with this style of curved-in keys in the 90s. I think it was Fujitsu-Siemens that made them (or before, Siemens Nixdorf, I'm not sure about that, could have been them as well). They always felt a bit spongey, but I found that I could type on them surprisingly fast!
Apropos... no HF in the LORAN box. That system worked at 100kHz :-)
Do the electrolytic capacitors at 15:11 blow the end out like that on their own with age or do they need power on to do that?
I was just going to sleep. :(
+Tom Wishaupt likewise
+Tom Wishaupt me too :c
+Tom Wishaupt me 2! 23:31:55
+Cheesecake 00:09
+Tom Wishaupt Psh. Who needs sleep when you can watch Mailbag!
For some reason or another the camera teardown video is made private, I was looking forward to watching it.
that antenna would actually be AWESOME for 5.8ghz FPV applications!!!
26:41 wow, that bag made it everywhere, ages ago i used to have that bag or one almost identical that i used for the first two laptops i bought myself, and i am practically on the other side of the planet from you (kansas).
I'd love a sinclair computer. I love the setup!!!
LORAN Transmitters can be picked up on Longwave!!!!!, love the beeping sound of them!!
Great video as always, some very interesting gear. Just a heads-up, I noticed the red Maxell battery in the Apollo GPS - if you decide to hang onto it you might want to pull that out - Apple used them back in the mid 90's and a lot of them are starting to explode, taking out the Mac's logic board (and any other parts around the battery) with them.
Nutty!!! Madness!!! Silliness!!!
I LOVE spherical keycaps!
I would really love to see more about the inside of these RF cans :)
But anyway, this is a great stuff!
What sort of socket is that AMD chip in on the last aircraft panel? It's huge!
24:45: The GPS Flybuddy has been approved in Germany as well. Look at the sticker on the side there.
What is with the Zener diode array at 9:30? Does the board use 8 different voltages?
They are likely to be signal diodes (such as 1N914 or 1N4148), though Zener diodes could be used for ESD protection.
I actually purchased a Sinclair ZX Spectrum+ about a month ago and I agree, keyboard is horrible lol
looks like they are overclocking the cpu, the A was a 4mhz model and I'm sure I saw a 4.4 mhz rock in there.
Loran operated in the 1.8-2.0mhz band.
I've actually flown an old Cessna 182, way back, that had the same autopilot in it. It's a single-axis (bank), so you have to still manually control the pitch.
I remember going to a 2-axis autopilot, being a huge deal.
I started flying in 1999, so I never even had to learn LORAN.
VORs and DME made those obsolete.
And, now GPS is making those obsolete.
So, LORAN was obsoleted by tech that is already obsolete...
That GPS receiver may actually have a higher update rate than modern versions, which are restricted by the military. I think they might have introduced this after selective availability was turned off. For a while all you could get was 4hz, but I've seen more recent chips that were 10hz.
II Morrow were bought by UPS Aviation Technologies (yes that UPS), and added to their 'Apollo' line, which was then bought by Garmin. If you think the avionics look old, wait until you see a Lycoming O320 engine, still sparked by twin magnetos.
I remember flying once with $30k worth of nav radios in the panel and we were using a ($100) yellow etrex on a flexi gooseneck suction cup'd to the windscreen; because it was a lot easier.
I've seen city survyers using GPS equipment before, I asked them how accurate, was told within 2cm. Crazy.
Was I the only one that was slightly fascinated that the navomatic, was almost balanced perfectly on the GPS?
More teardowns during mailbag!!
The adjustments at 14:28 are: (supposedly to adjust the various op-amp gains and nulls)
HDG Gain = Heading Gain
HDG Null = Heading Null
NAV 1 Null = Navigation input source #1 null
NAV 2 Null = Navigation input source #2 null
NAV Integrator Null = The nav intercept null (my best guess)
It can be annoying flying with one of these things that is not adjusted correctly. Sometimes the aircraft altitude or heading will oscillate under autopilot control while it is "hunting" for the position it wants.
Yay for spectrum. My very first computer was a spectrum+, lovely computer
At 28:56 RHCP means right hand circular polarisation..
Awesome stuff! No excuse in not using the big knife though!
Alright Mr. "OutaTime"
At 28:48, do you see the traces in the center of the antenna? does it not resemble a flux capacitor? I guess it was unpopulated, so you know what that means.
it wasnt the special edition.
5:06 Video is private!? :( :( :(
+Power Max He probably keeps them private until youtube has rendered the 1050p resolution as well. Otherwise people are gonna complain about the resolution, because most don't understand how yt works. You never win.
+Jack White That makes sense.
+captian k'Lang
Dear captian k'Lang I want to express my sincerest apologies for my failure to check for typos. I realise that my oversight was totally inexcusable and disrespectful. I can only imagine the distress I have caused to everyone and the damage that it has done to your trust in me.
Yours sincerely,
Jack White
Great stuff! Love the avionics and GSM phone . . . *Big* thumbs up! Good to see something from a different industry for a change (not to mention I'm a pretty huge aviation fan) . . . . I don't think LORAN is used for anything at all today . . . FYI it operated at very low frequencies, around 1.8 MHz just above the US AM broadcast band.
another awesome video! You've got to come up with some other way of showing a close-up of the mailbag items. Holding it, out of focus, close to the camera Stinks. We need these details Dave! Thumbs up here.
Please return to this mailbag format in the future too! Otherwise lately I have to skip forward all the time to find the 2 minutes out of a 40 min video that actualy have some electronics. I love your long videos but I love them much more when they are about electronics!
This is an old video and you were probably already told this but II Morrow was purchases by UPS and was eventually sold to Garmin.
I got one of those old Speccies for ONE POUND back in the early 90s! Primary school "jumble sale" find... There was a note attached to it which said "there is a fault with this item but we do not know what". No idea what kind of fault they were referring to but it seemed to work fine until I got bored and went back to the C64 :D
At 29:08, the acronym says 'RHCP', but when spelled out it is 'Left Hand Circular Polarized'? So is it a right handed or a left handed patch array?
+MLeoDaalder Did I actually type that? Doh.
There is a german Bundesadler on the Case of the GPS and some sort of american certification. Do other countries not require a certification for flight gear?
Who would possibly eat some components from inside a satellite phone?
+mackocour they even wrote it in 5 different languages: Danish, English German, Dutch and French
Yep, Liberty Bell is still here in Philadelphia...
at 28:56, that's actually an unpoulated flux capacitor. See:
+John Street www.pneumatictips.com/wp-content/uploads/2015/03/flux-capacitor.jpg
The keyboard dous have a RAND key though... Got to give points for that :-)
DO YOU GIVE THE TEARDOWN PARTS TO OTHER BUILBERS TO USE OR DO YOU CAN EM
"Welcome to everybody's favorite segment, FAILBAG!" Just kidding, but every time he says mailbag I can't help but think "failbag". I have no life. "I love a big package!"
Dave, I recall Fran sending you some nixie tubes for you to do a project. Is it something you might consider do, for example a bedside clock? It would be nice! Nixies are AWESOME!
Greetings from Portugal!
Get Dave2 to focus pull and if he doesn't want to do that (wouldn't blame the guy) have him create one that works by foot pedal for you to use when waving items for closeups!
What did you do in the end with all the server DDR3 memory? I see the box I sent mine in still sitting over your left shoulder... :)
Loran system wasn't popular in civilian aviation, VOR/DME system is the more popular, VOR stand for "VHF omnidirectional range" and DME stand for distance measuring equipment.
HDG = Heading(direction of travel)
RHCP = Right Hand Circular Polarized (LHCP is left-hand)
Where did you grit that knife
22:44 Mitsubishi IC, never seen one of those.
11:36 That is literally a picture of my backyard. Montana blokes unite!
Fran has a beautiful signature
If i received like this parcel like this, i will feel exciting exactly as your feeling. But I will deep study the purpose why the engineers design that ways.
How did you miss the names on those avionics, II Morrow = Tomorrow
The typewriter with the rotating ball was the "IBM Selectric"
en.wikipedia.org/wiki/IBM_Selectric_typewriter
Well I'd bet that someone at the design team on the Sinclair had a Underwood typewriter. The concave keytops are a dead giveaway.
National Treasure is one of my guilty pleasure. I honestly really liked this movie ^^"
Love that bloody knife :-)
your teardown of the cam is pivate why?
The Navomatic was nodding at 13:53. Creepy...
+Duan van't Slot Spooky!
Dedicated unboxing bowie. I like it.
yay for teardowns, boo for private...... lol.... excellent.
I seem you are very damn exciting to study inside the antique circuit board than put it for exhibition.
slic: Subscriber Line Interface (card/circuit)... that may allow connection of a normal landline phone to the thing too!
+TheChipmunk2008 Nifty, but what's the advantage? Maybe I'm not imaginative enough, since I don't understand why you would want to hook a satellite phone into a landline and not just use the handset built in to the sat phone. Even for emergency backup comms at a remote facility, I would think the portability would be more important in case of evacuating the building (fire, etc).
+zrobotics Not honestly sure, maybe to allow equipment that expects a landline to use that instead in an emergency? For the price they charge(d) for those phones, adding the functionality wouldn't have been difficult
***** And now I'm imagining some poor schmuck paying several bucks per minute to connect to 14kbps
+zrobotics Given the age of that satphone, it would make sense if you could connect a fax to it.
+Mikael Pedersen It was likely also done to allow connection of a dialup modem since there were no obvious serial ports for computer data. Satellite phones were/are often used in locations with no communications infrastructure, so the ability to transmit field data back to home base was often desirable despite the high per minute charge of satellite.
The teardown video claims it's private
Lots of analog comparators in autopilots