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Do Old Computer Modems Still Work?

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Can I still use old modems to get my old computers online? I've read multiple times that it doesn't work, but nobody really explained why. It'd be neat to be able to connect, like, my Apple //e to the phone line and bring some of my old computers to my friend's house, and try dialing each other's numbers, and see if we can "telecommunicate".

Oh, speaking of connecting computers, can I use my Commodore VIC-20 to talk to someone who uses, for example, a TRS-80 Color Computer? Or are the communication-system-language-thingies proprietary?

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If you and the other party both have an analog telephone line, the connection should still work. My ISP continues to support dial-up access, and I was told that is because there are a few customers who still make use of it.

 

I understand that the C-64 (and the Atari 8-bit) can support simple graphics via modem communications. When connecting with e.g. a Coco, however, you are going to be limited to straight, plain ASCII text.

 

Note too that the maximum communication speed is going to be 2400 baud, if not 1200; I do not know if the C-64 can go faster, but the bit-banger series port in the Coco cannot reasonably do so.  

 

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even with packet switched POTS (VoIP and pals), very low speed connects should be possible if the compression does not smash the integrity of the waveforms.  Your mileage may vary though.  (One early CODEC intended for packet switched phone systems was GSM.  It sucks, and will make even 300 baud not connect well. However, other packet-switched codecs will work fine, like adpcm, and u-law/a-law, with varying degrees of smashing, meaning you need to set your connect rate accordingly and do some math.)

 

That probably means using a manually doctored AT handshake sequence though.

Edited by wierd_w
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I know you can get a Dreamcast online with its modem and a Raspberry Pi, so I googled to see if it'd work.

It does

 

 

Granted this touches on BBS's that are online but you may be able to do more.

Edited by Gamemoose

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There are still active dial up BBSs.  I typically use an old ass 1200 baud modem because it looks cool and there's really no need to go higher.  I've used 4800 no problem...that's the highest my favorite terminal program for my Model III supports.  Technically the computer will handle up to 9600 and I'm sure my phone lines do too.

 

FAX machines use modems and are still a reality, and no matter what idiots claim, they are still heavily used in the business world.

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2 hours ago, Turbo-Torch said:

FAX machines use modems and are still a reality, and no matter what idiots claim, they are still heavily used in the business world.

 

Especially in Japan, for some odd reason.

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I sent a fax earlier this year with a fax modem over a VOIP connection. It worked. Based on my experience, I don't think you necessarily need an analog phone line.

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25 minutes ago, batari said:

I sent a fax earlier this year with a fax modem over a VOIP connection. It worked. Based on my experience, I don't think you necessarily need an analog phone line.

VOIP can be a little funny with faxes. How it compresses data can screw up a transmission. 

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4 minutes ago, Gamemoose said:

VOIP can be a little funny with faxes. How it compresses data can screw up a transmission. 

I had to send a fax to a government agency. I wanted to email a pdf but that apparently wasn't legally acceptable. They later scanned it and put it online and it seems that it went through with no issues.

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6 minutes ago, batari said:

I had to send a fax to a government agency. I wanted to email a pdf but that apparently wasn't legally acceptable. They later scanned it and put it online and it seems that it went through with no issues.

I shoukd have been more specific, sorry. One of my clients transitioned most of their lines to VOIP this past year. Some of the multifunction machines they have had issues receiving over VOIP.  After digging around forums and such, what I posted was the explanation. The machines (all Xerox) don't seem to have the option to adjust the baud rate, which might help. 

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24 minutes ago, Gamemoose said:

VOIP can be a little funny with faxes. How it compresses data can screw up a transmission. 

From what I understand, VoIP uses a 3GPP codec similar to AMR but with variable bit rates in the stream to compensate for varying congestion conditions.  I have tested and it is possible to get 300 baud (Bell 103) encoding to work on 8kHz AMR, so I expect 300 baud will work over cellular.  I have not tested 1200bps (Bell 202a) or above.

 

I will be testing some stuff at VCF-SE this year.

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14 hours ago, ClausB said:

Mine doesn't.

 

IMG_20191222_151913.jpg

 

 

Well of course it doesn't!

 

You need ONE OF THESE to do that kind of thing!!

 

51mSXWZaaaL._SL1000_.jpg

 

Conveniently available on Amazon even! (ducks)

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13 hours ago, Gamemoose said:

I shoukd have been more specific, sorry. One of my clients transitioned most of their lines to VOIP this past year. Some of the multifunction machines they have had issues receiving over VOIP.  After digging around forums and such, what I posted was the explanation. The machines (all Xerox) don't seem to have the option to adjust the baud rate, which might help. 

 

Can you modify the AT command sent at pickup?  Some multifunction devices offer that instead of a baudrate control. (which in my opinion, is vastly more robust, as you can set much more than just baud rate with a custom AT string.)

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(damn, I am dominating this thread, sorry in advance...)

 

So, Digging into the whole "Modem over VOIP" thing, I landed on this old project.

https://sourceforge.net/projects/t38modem/

 

It is a software SIP endpoint that presents itself as a modem on either windows or *nix OSes. (packages for both.) It is intended to enable fax machines and modems to operate on a SIP network.

 

 

Now I am wondering if I can set up a BBS on that redundant NAS box I have using some free POTS accessible SIP numbers.... (It runs Linux.)

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On 12/23/2019 at 4:41 AM, wierd_w said:

 

Can you modify the AT command sent at pickup?  Some multifunction devices offer that instead of a baudrate control. (which in my opinion, is vastly more robust, as you can set much more than just baud rate with a custom AT string.)

I don't think so, at least with my initial research on adjusting baud rates. Departments that had problems with the Xerox MFP's shifted to an online solution. Reality was they really didn't fax or receive faxes nearly as much as they thought. It was basically a legacy mentality. Those departments that did heavy faxing had cheap MFPs their department bought at a Best Buy and I think they got something else. I handle a specific department mostly, so I only hear whispers of goings on in my concrete cave.

 

 

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Were phone sizes standardized? What if your phone didn't fit in your acoustic coupler?

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At the time, the ONLY maker of telephones as ATT.  Due to government sanctioned monopoly powers.  As such, the handset was always the same size and shape.

 

It was a monstrous fight to get modems on the phone system to begin with, and ATTs blowback on it is partially why there even WERE acoustic couplers. Since modems were not made by ATT, ATT did not want them directly connected to the phone network.

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There was no standard handset.  Before anyone even knew what a home computer was, there were trimline phones with the dial inside the handset, tacky French phones that could only be popular in the 70s, phones with squared off handsets, round space age phones, novelty phones...  None of those would work with an acoustic coupler.

 

That said, most households had a few Princess and/or Western Electric 500 phones still in use.

 

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Prior to 1968, AT&T did not allow (3rd party!) electrically wired modems on the telephone network.

https://www.techradar.com/news/internet/getting-connected-a-history-of-modems-657479

 

Quote

Running along in the background was also some hefty legal action and competition as AT&T initially prevented customers from connecting devices from other companies to their telephone lines.

 

However, thanks to Tom Carter the Carterfone Decision of 1968 soon saw this unfair advantage taken away from AT&T.

 

It was in the 50s that ATT got told in no uncertain terms by the US Govt that they had to divest western electric and stop being the sole supplier of telephones in general.  Since this was only about a decade prior, many households and businesses had incumbent handsets made by Western Electric.  This is why acoustic couplers (which were required prior to the 1968 decision) were designed to work with the Western Electric designed handset.

 

Western electric, being spun loose from ATT's reigns in the 50s, was still a dominant manufacturer of such handsets in the intervening years.  By the 80s, stand-alone wired modems started appearing, but before then the acoustic coupler was the only game in town.

 

Since very few people WANT that 50lb Behemoth on their desks or walls these days, Western Electric handsets are not very common. So, if you have an old acoustic coupler based modem, and wanted to try using it, you are gonna have problems.  There are novelty products, like the one I linked earlier, that could facilitate that, but really, it's not worth it IMO.

 

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The acoustic couplers were a thing from '78 to maybe '82 at the latest.  There was no shortage of wild looking phones in the 70s, so the handsets were not all the same.  People didn't hesitate to save money and add style to their home by purchasing their own phone and sending back their rented phones to Ma Bell.  And like I already said, if you needed to use an acoustic, odds were good there was still a Princess or Western Electric somewhere in the household.

 

If the year was 1977 and you just brought home your brand new TRS-80 Model I and didn't have a phone with a standard handset to use with your new acoustic coupler (not really sure what or who you'd be dialing into), you could head back to Radio Shack and pick up a brand new Western Electric style phone for $34.95 or a refurbished one for $14.95 catalog #279-371.

 

If you have a landline and want to use an acoustic coupler today just for the thrill of it (and I think that's what you're wanting to do from reading some of your posts), simply buy a real vintage phone.  Hit eBay, Craigslist, flea markets, your old neighbor a few doors down and get yourself a Western Electric or Princess style phone for under $20 bucks.  If it's not smashed up, odds are it'll work as they were next to indestructible.  You'll also need a 4 prong to RJ11 adapter (unless your house is older and still has some of those old style wall jacks).

I would also stick with touch tone, rotary dial phones use pulse and some telcos no longer support that. 

 

A side hobby of mine is old telephones...they're incredibly cool, everybody loves them and they still make and take phone calls as always.   

I have a hotline red 1958 Bell Western Electric in my rec room.  Been in my family for 62 years and it works perfect.  Also have an original 1st year touch tone Mickey Mouse phone in my office.  My 80s game room has a period correct high tech looking wall phone called the Fiero (not related to the car).

One of my favorites is a cordless phone I got for my birthday in the very early 80s.  It's so old, it has a push button keypad, but only dials out in pulse and the base and handset are covered in brown leather.  It's made by ITT, is pushing 40 years old and still has a 1/2 mile range to it.  That one has some stories attached to it involving police and detectives knocking at my parents' front door. :lol:

 

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2 hours ago, Turbo-Torch said:

One of my favorites is a cordless phone I got for my birthday in the very early 80s.  It's so old, it has a push button keypad, but only dials out in pulse and the base and handset are covered in brown leather.  It's made by ITT, is pushing 40 years old and still has a 1/2 mile range to it.  That one has some stories attached to it involving police and detectives knocking at my parents' front door. :lol:

I had a cordless like that in the early 90s.  It operated on an unlicensed band, the frequency of which I cannot recall OTTOMH, and had an extendable antenna of around a foot and a-half.  It, too, had a range of a good half-mile or so.  I do not remember if it dialed pulse or tone -- I am pretty certain it could do DTMF.  It had an on-hook button just below the microphone instead of the push-on/push-off of more modern phones, so you laid it down on its face to hang up.

 

That on-hook button was part of its demise.  My father destroyed the phone by slamming it down on the dining room table one day when he and my mother had an argument by phone.  Though I could have a couple of years later, at the time I lacked the necessary skills to repair it and the local Radio Shack wanted more money to fix it than I had available.  Dad threw it away when he discovered it was not fixable.

 

I have an odd compulsion to collect old telephony every so often.  Nothing really spectacular, mostly stuff vintage of my youth.  Most of the stuff my family had has long since been discarded or sold at garage sales so I have been relegated to picking up similar items as I can.  For instance, an ITT kitchen phone with rotary dial, a couple of desktop phones with push-button pads instead of the rotary we had.  Our first DTMF phone was an old princess-style phone with tone generation circuitry rather than solid state, and pressing multiple buttons in a column or row would produce a single tone of the column or row rather than both tones.

 

I have managed to keep hold of every modem I owned from the beginning of my modem days so those had not needed replacement.  Like my other collections, with the exception of the spares, these phones do get used and the modems will see demonstration every so often.  I have a four-port phone line emulator which I have been playing with to connect systems together for the fun of it, especially when I found my old BBS disks and wanted to see how it looks remotely.

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The ITT cordless is amazing.  About every 15 years I'll replace the batteries in the handset and that's it.  It's 3 AA rechargeables with soldered tabs linking them together.

 

BITD, there were only a few set frequencies for those phones and no real security.  On mine, when you put the handset on the cradle to charge, it did lock the system out and there was an override button if you wanted to turn the security off.  The cheaper phones had nothing.  It didn't take long for me to figure out I could roam around town with the handset on and tap off other phone lines that were on the same frequency.  This was a godsend to me and my friends who loved to make prank phone calls. :lol:

It also saved my ass because we sort of over pranked one particular place and they had a tracer put on the line.  One day a detective showed up at my parents' house as one single call was traced to our number.  I denied it and the police couldn't prove anything because they had at least a dozen other traced numbers between two different counties and none of it made sense, such as 90 year old couples and businesses.  I think in the end they assumed the telcos tracing system was really messed up.  I did get the stink eye from my mom & dad because they knew I was behind it, but didn't have a clue as to how.

 

So much nicer than a disposable Chinese POS that you'd buy today.

 

foneitt.jpg

 

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On 12/31/2019 at 10:56 PM, Turbo-Torch said:

 tacky French phones that could only be popular in the 70s

 

My Grandmother had one of those white-and-gold monstrosities with the massive handset. It sat in her living room, and I am unsure that it was ever actually used. It was eventually disconnected for some reason, but it remained in place until we sold the house in 2001! 

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