[HN Gopher] A 6 channel GPS receiver from 1993
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A 6 channel GPS receiver from 1993
Author : edent
Score : 193 points
Date : 2023-11-04 10:27 UTC (12 hours ago)
(HTM) web link (mastodon.sdf.org)
(TXT) w3m dump (mastodon.sdf.org)
| thomasfl wrote:
| That's cute!
| roland35 wrote:
| Adorable! As a former EE we often put little jokes and Easter
| eggs in prototype PCB designs. Sometimes they made it to
| production!
| dan-robertson wrote:
| More on gps: https://lea.hamradio.si/~s53mv/navsats/theory.html
| danieldk wrote:
| Another great explanatory page I have seen is:
|
| https://ciechanow.ski/gps/
|
| Comes with a lot of animations and interactive elements.
| Admittedly, I haven't gone through all of it yet since it so
| detailed, but it is marvelous.
|
| Earlier discussion:
|
| https://news.ycombinator.com/item?id=36180316
| agumonkey wrote:
| archived link for image links seem dead
| https://web.archive.org/web/20060711045257/https://lea.hamra...
| tpmx wrote:
| It sold for just $12 yesterday. (Some more shots here, too.)
|
| https://www.ebay.com/itm/274506300217
| WarOnPrivacy wrote:
| I don't think it sold. The listing ended. Also add $6.50
| shipping. Still worth it.
| tpmx wrote:
| But it literally says: "Sold for: US $12.00"?
| kebman wrote:
| It's a bit on the side, but I remember my father telling me that
| the PCB's he sold to the Eastern Bloc were often adorned with
| microscopic greetings in Cyrillic, though the Russian spelling
| was often pretty bad.
|
| Just like now, the Soviet Union was under heavy sanctions, and
| they weren't allowed to receive the latest computer tech. The
| various companies had ways around this, though, and the saying
| was that they'd purposefully design their boards so that Russian
| engineers could "tamper" with them in order to achieve higher
| than allowed clock speeds.
|
| Anyway this cute board just made me think of that, so thought I'd
| share it.
| secondcoming wrote:
| Great, and now they have Kinzhals
| gambiting wrote:
| It's incredibly racist, offensive and ignorant to assume that
| "Eastern Block" means just Russia. Many former "eastern
| block" countries nowadays are firmly with the west and oppose
| Russia and their stupid invasion with all their might. Being
| bundled together with the Russians is the most personally
| offensive thing I've ever read on HN.
| assusdan wrote:
| Could you please also stop bundling all russians together?
| Not all of us oppose "the west" and support our stupid
| invasion.
| gambiting wrote:
| I didn't say either thing though? I said many of us here
| in the former Eastern Block oppose Russia - and I
| personally find being bundled with the Russians
| offensive, as I am not a Russian. Anything you read into
| it beyond this point is your own interpretation.
| 5e92cb50239222b wrote:
| Uh-huh, yet it's somehow not racist, offensive and ignorant
| to blame all Russians for everything now. Some of you guys
| have lost all the high moral ground that you once
| supposedly had.
|
| I have a working theory that long years of "oppression" in
| many Western societies of not being able to criticize any
| group of certain ethnicity, nationality, culture, or
| religion resulted in a buildup of sorts, so when it became
| okay to pour shit on ethnic Russians and citizens of that
| country (between which you make no distinction -- do you
| make a distinction between Jews and Israel?), it's like the
| flood gates were opened. All the hate and vitriol
| accumulated over the years is directed at a group that one
| is allowed to hate.
| teddyh wrote:
| As soon as a new subset of people have been designated as
| part of the outgroup, they are basically fair game for
| everybody to get their kicks in1. And boy howdy do people
| love some fully justifiable carnage.
|
| 1. <https://news.ycombinator.com/item?id=33802663>
|
| (This is a re-post of
| <https://news.ycombinator.com/item?id=33913979>.)
| gambiting wrote:
| I feel like you've replied to the wrong person maybe?
| bee_rider wrote:
| I wonder if it was the pre-90's black/grey market, or the
| intervening decades of open trade.
| mananaysiempre wrote:
| I'd guess the former, but only because I'm honestly
| surprised _anything_ designed or manufactured under
| government mandate post (generously) 1985 actually works.
| The collapse of the Soviet Union might have marked the
| start of open (!) looting, but with rare exceptions Soviet
| research organizations have been in pure subsistence mode
| for a decade or more before that.
| bee_rider wrote:
| The Kinzhal is a sort of heavily modified Iskander, I
| mean all ballistic missiles are rocket science but it is
| not some super futuristic weapon.
| baybal2 wrote:
| Betrayers of The Free World reap the benefits of living in The
| Free World the most, and advance ahead on the social ladder
| towards decision making positions, perpetuating these bad
| decisions.
|
| And people who did the right decision, have to pay twice. One
| is the opportunity price, and another is the externality price.
| GuB-42 wrote:
| If sharing useful tech is betrayal, I wish there would be
| more traitors. On both sides.
| ck2 wrote:
| Garmin had the 100 series in 1990
|
| Neat history of GPS units
|
| http://retro-gps.info/page33/index.html
|
| But what's really interesting is the first GPS watch, the
| Forerunner 101 in 2003
|
| https://www.garmin.com/en-US/p/231
| ShamelessC wrote:
| > Why is it shaped like an ambulance? Good question.
|
| Was hoping there was an actual answer for that question. Or am I
| missing something? Otherwise reads like "good question, who
| fucking knows!? certainly not me the person making the
| assertion!"
| skhr0680 wrote:
| Am I missing some sarcasm, or do you honestly think that the
| board in question doesn't look like an ambulance?
| InCityDreams wrote:
| But _why_ is it shaoed so?
| skhr0680 wrote:
| Why would someone in 1993 have had the foresight to think
| that they might need to know their location to within a
| hundred meters or so?
| ShamelessC wrote:
| No sarcasm. Yes, it looks like an ambulance (seemingly
| deliberately). The tweet/fart/whatevertheyrecalled just has
| strange choice of phrasing implying they will follow up on
| this, then they don't. _Why_ is it an ambulance? Well who
| cares, I guess - but the author of the
| poof/squirt/whatevertheyrecalled is the one who draws
| attention to it in the first place.
| skhr0680 wrote:
| Whoever designed the board may have just done it as a joke,
| but I think giving the coastguard etc. an idea of your
| general location when in distress would have been a good
| civilian use of GPS in 1993
| makomk wrote:
| It's a several decade old piece of hardware that was likely
| produced in extremely limited quantity, so finding the
| answer to that is probably not going to be easy. Presumably
| it was produced as a promotional item made to promote their
| GPS receivers for some kind of safety application that the
| ambulance shape is a reference to, but good luck confirming
| that in 2023.
| TedDoesntTalk wrote:
| The original GPS receivers in the late 80s and early 90s did not
| have maps. And they used LCD screens. The one I owned by Lowrance
| required 6 AA batteries. Not AAA. Not rechargeable. Optional
| power through a cigarette-auto cable, but that's not helpful when
| on foot. It burned through batteries like crazy.
|
| I owned this one:
| https://web.archive.org/web/20231104153749/http://retro-gps....
| (Lowrance GlobalNav Sport) 160 x 160 pixel display. It weighed 2
| pounds with batteries.
|
| It provided latitude, longitude, and heading.
|
| Thought I would use it hiking but it was just too big to be
| anything but a toy. You inserted a cartridge, specific to your
| geographic area, if you wanted it to display names of
| towns/cities (data on the cartridges):
|
| https://www.ebay.com/itm/314936082464
|
| It did have "waypoints" (lat/long bookmarks, essentially) that
| allowed you to plot a line as you traveled. It could tell you how
| far you were to different waypoints you'd previously entered.
| IIRC, it had a serial connection for waypoint download to a PC.
| People tried sharing waypoint series -- "routes" -- but it just
| never really had much success as I recall. It was just too
| cumbersome.
| metadat wrote:
| Which model was yours? This page appears to show every model of
| handheld GPS ever made, and Lowrance has 4 entries.
|
| Thanks for sharing this, I never had the chance to see one of
| these units. It's so weird now to imagine GPS with no map!
|
| P.s. What does a six-channel GPS receiver even mean? Is more
| channels more better?
| TedDoesntTalk wrote:
| Here's a better picture of what I owned. It had a huge hard-
| plastic case:
|
| https://www.ebay.com/itm/314936082464
|
| The antenna flipped up and doubled as a screen protector:
|
| http://retro-gps.info/photos/files/page2-1023-full.jpg
|
| https://i.ebayimg.com/images/g/zxUAAOSwDspimA3F/s-l1600.jpg
|
| Sorry, I don't remember what 6-channel means. I would guess
| it could receive data from up to 6 satellites? Don't know.
|
| IIRC, this cost about $700 but cartridges were extra. Very
| expensive for the time. It worked without the cartridges, but
| I think it only displayed lat/long then, or in any case much
| more limited info. The carts added more info like
| town/city/state.
|
| Unfortunately, I could not find any YouTube videos of early
| GPS receivers.
| metadat wrote:
| Thanks @TDT for your prompt and rapid reply, always nice to
| connect with such a generous person who indulges me :D.
|
| What a spiffy looking unit, it looks like belongs mounted
| in the dash of a 198x Mercedes, Porsche, Corvette, Bronco,
| or similar alongside one of those old school built-in car
| phones.
|
| Archive links of the eBay resources:
|
| 1a. https://web.archive.org/web/20231104152903/https://www.
| ebay....
|
| 1b. https://archive.ph/QxwrN
|
| 2a. https://web.archive.org/web/20231104153359/https://i.eb
| ayimg...
|
| 2b. https://archive.ph/crpGm
|
| (Adding because of how many broken eBay links I've
| encountered on forums over the years.. it's always
| frustrating, haha.)
| TedDoesntTalk wrote:
| You're welcome! This is the best photo in my opinion --
| shows the antenna up (not covering screen), unit is
| powered on, and the unit itself is in excellent
| condition:
|
| https://web.archive.org/web/20231104153749/http://retro-
| gps....
| skhr0680 wrote:
| https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=2.
| ..
|
| > The receiver has six channels that continuously track four
| primary GPS satellites and sequentially acquire and track all
| other visible and healthy satellites on the fifth and sixth
| channels.
| jdietrich wrote:
| _> What does a six-channel GPS receiver even mean? Is more
| channels more better?_
|
| The operating principle of GPS is more complex than I can
| usefully summarise in a comment, but essentially the
| satellites are continuously broadcasting an extremely
| accurate time signal that the receiver uses to calculate the
| time-of-flight to each satellite. GPS receivers need signals
| from a minimum of four satellites to provide a location fix.
|
| There are usually more than four satellites visible, so
| additional channels allow for more than the minimum number of
| signals to be received. this can provide improved accuracy,
| faster time-to-first-fix and better resilience to
| interference. If you're receiving five or six signals, you
| don't lose your positioning fix when one of the satellites
| moves below the horizon or is obstructed by terrain.
| Reflected signals can cause error, because the time-of-flight
| of the signal will be greater than the actual distance to the
| satellite; extra channels allow these errors to be
| compensated for.
|
| For a long time, GPS receivers typically had no more than 12
| channels, which was the maximum number that would actually be
| useful given the limited number of satellites in the original
| GPS constellation. Since then, many other navigation
| satellite constellations have launched, so between 40 and 60
| navigation satellites are typically visible at any moment.
| Receivers have commensurately improved, with even basic
| receivers often having upwards of 48 channels.
| eastbound wrote:
| How does encryption work on GPS signals? Since it seems the
| military have access to better accuracy, it's not just a
| wavelength that is broadcasted.
| jdietrich wrote:
| Prior to 2000, the civilian signal (C/A code) was
| deliberately degraded by the addition of small random
| variations in the time signal, but this is no longer the
| case. A separate military signal (P-code) still exists,
| which is encrypted in order to prevent spoofing; to my
| knowledge, the encryption scheme used for the military
| signal is still classified.
| stcroixx wrote:
| Garmin handheld unit in the early 2000's still had an LCD
| screen. I still have and use mine as a backup.
| supportengineer wrote:
| I have the eMap. Still works. In 2002 I tethered my laptop to
| my phone and connected the eMap to the laptop. I had custom
| Java software that would read my position from the serial
| connection, and then post it to a custom PHP page, and there
| was a different page where you could view my position on a
| Yahoo Map.
| lm411 wrote:
| That Lowrance is a monster. Pretty cool though.
|
| My first GPS receiver was an old Magellan. I can't recall the
| model, but mid 90s, very basic features. Eventually after
| turning it on it would get a fix, and give you coordinates /
| speed / bearing. No names of towns or anything like that though
| it did have support for some number of waypoints.
|
| I typically used it for multi week hikes through the rockies
| where I was navigating primarily with topo maps & compass, and
| about once a day I'd turn on the GPSr to validate my location.
| It was too much of a pig on batteries to use it any more often,
| but, it was a reasonable size for hiking.
|
| Totally different world vs the Garmin GPSMap 66i I currently
| use, but, I'd probably trust the old Magellan more than I do
| 66i on week/longer excursions.
| aziaziazi wrote:
| Wondering why << No rechargeable >> ? I recall rechargeable AAs
| in late 90, didn't they exist in early 80 ?
| hexmiles wrote:
| Not OP, but i remember having a camera that use AAs and would
| not support rechargeable. While it powered up, it would not
| take photos and instead shutdown. I think they used to be
| able to deliver less power, also when i put them in the
| gameboy the little led was a tad dimmer that non rechargeable
| one even when fully charged
| ljf wrote:
| Even in the early 90s my good rechargeable batteries (AA)
| only put out 1.2v when freshly charged and dropped lower than
| that as they ran. They also ran far shorter than duracell or
| similar expensive batteries.
|
| So one the voltage may have been too low and two the usable
| loge might have been too short for these power hungry devices
| _whiteCaps_ wrote:
| I had a radio that could handle rechargeable vs non - it
| included a dummy AA battery that you used when using non-
| rechargeable batteries, so you'd use (IIRC) 7 rechargeables +
| 1 dummy or 8 rechargeables.
| saltcured wrote:
| The first "portable" GPS receiver I ever saw was during a tour
| of a relative's military base in the mid to late 1980s.
|
| It was mounted in a travel case where the lid removed exposed
| the control panel. I want to say it was about the size of a
| shoe box. Similar in length and height to one of those hinged
| metal ammunition cans, but wider if I remember correctly. It
| seemed hefty enough to have a lead-acid battery inside, but
| they did not give details.
|
| You set it on the ground and waited minutes for a fix. Then it
| just displayed numeric grid coordinates of your location with
| segmented digit display cells somewhat like a 1970s calculator.
| thom wrote:
| GPS seems fairly pedestrian now but my dad had one of the early
| Garmin models in the 90s and it was a kind of magic back then.
| Even outside of the actual location info, just seeing this thing
| in your hand listening to satellites up in space felt incredibly
| powerful. Later on you could get units compatible with Windows CE
| and mobile devices and it was easy to see why it would be a
| killer app on smartphones. It's sad that the complexity and
| cleverness is all hidden now.
| tpmx wrote:
| I mean, both GPS and WiFi was super exciting stuff in the early
| 2000s. There was a GPS magazine for GPS terminal enthusiasts
| (!). It's still sort of around: https://www.gpsworld.com/.
| callalex wrote:
| Also kids these days don't know the pain of GPS taking 3-10
| minutes to get a position fix without almanac data.
| thom wrote:
| Yeah, navigating a big city meant finding a crossroads where
| you might be able to see a bit of sky. I used to wear a
| shoulder bag and attach the antenna to the strap to stay
| locked on.
| mareko wrote:
| Or the days before GPS where taking a road trip inevitably
| resulted in a big argument with your partner about directions
| spookthesunset wrote:
| Back then even light tree cover would sometimes trash the
| signal enough to lose position.
|
| While modern GPS can get a position fix pretty quick, a cold
| start on standalone units can still take a while before it
| discovers enough satellites.
|
| The crazy thing to me is now days my little tiny watch can do
| Wifi, Several Bluetooth protocols, 5G, NFC, Wireless charging
| and probably some other stuff I'm forgetting about. Oh and it
| supports a variety of global navigation satellite systems.
| Don't forget the high-res OLED display too. And the fact it
| is fully watertight.
|
| All that while having a fairly impressive battery life.
| rz2k wrote:
| Take a look at the https://phyphox.org/ app for lower level
| access to the sensors on Android and iPhones. There is a GPS
| section that gives you coordinates but unfortunately doesn't
| tell you about each satellite. The precision of other phone
| sensors seems even more amazing.
| nulld3v wrote:
| You could also try https://github.com/barbeau/gpstest if you
| are looking for something more GPS focused.
| 3760451 wrote:
| 3760451
| 3760451 wrote:
| Hos
| mattew wrote:
| The interesting thing about GPS back then was that the location
| data you got back were randomly slightly incorrect every time you
| got a reading. I'm pretty sure this was so it wasn't useful for
| military purposes.
|
| I think it was called differential post correction but if you had
| a base station with a known location you could snap your
| incorrect points to the difference generated at that correction
| level and get the true location after the fact.
|
| Source: GIS major in late 90s when this stuff was a lot more
| magical
| toomuchtodo wrote:
| https://www.gps.gov/systems/gps/modernization/sa/
|
| Selective Availability?
| mattew wrote:
| That's right. It was selective availability and you used
| differential post correction to clean the data up and get
| accurate locations for the data you were capturing. Thanks
| for the correction!
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(page generated 2023-11-04 23:00 UTC)