1 Feb
2025
1 Feb
'25
12:05 a.m.
In the early 70s my employer used stand alone data entry tape units in our remote
locations. We started with NCR units but then switched to Tally. In the late afternoon the
data would be transmitted to the home office in Chicago for processing. Also using
NCR/Tally units. We used Racal-Milgo modems. These things were about the size of a large
home stereo receiver. We started at 2400 baud. The units could do 3600 or 4800 (I don’t
remember which) if a circuit board strap was moved.
We had locations in many cities/towns all the way out to Montana. It was decided that we
needed to have the ability to switch between 2400 and the faster speed when possible. We
did not want to have the locals power off the modem, open it up, remove a card and move
the strap. So I got volunteered to come up with a plan.
I found a place in the modem where I could mount a switch. Luckily the modem had a sliding
panel on the front so the locals would not have to open the box top. Went to our fleet
garage where they had the tools I needed. I made a bunch of aluminum brackets for a tiny
toggle switch. Added wires to the switch.
It was also decided that we could not trust the locals to do the switch install. So part
of the plan included me going to all the locations and doing the install. I did not have a
car at the time so I got a fleet car. Headed south to Kentucky then turned west. Don’t
remember all the states I hit but I believe the last place I hit on the way home was
Rockford. I remember being on a back road in Montana and I took a picture of my
speedometer. I was doing 65. This was when there was a countrywide speed limit of 55. I
can’t be limited by the Man. :)
Back at the home office we had 6 NCR/Tally machines and only 4 modems. I built a plug
panel box that had everything wired to it and used telephone jack plugs to connect the
Tally’s to an available modem. The box also had switches for the modem speed.
I now forget how long the whole process took. Put my DeVry AAS degree to good use. :)
1 Feb
1 Feb
12:20 a.m.
On 1/31/25 16:05, Donald Whittemore via cctalk wrote:
In the early 70s my employer used stand alone data
entry tape units in our remote locations. We started with NCR units but then switched to
Tally. In the late afternoon the data would be transmitted to the home office in Chicago
for processing. Also using NCR/Tally units. We used Racal-Milgo modems. These things were
about the size of a large home stereo receiver. We started at 2400 baud. The units could
do 3600 or 4800 (I don’t remember which) if a circuit board strap was moved.
Those rack-mount Milgo units were built like battleships and very well
regarded in the industry. My first "high-speed" modem was a Racal/Vadic
3451 that, IIRC, could do 2000 bps when talking to another 3451 using
RV's proprietary protocol.
--Chuck
1:44 a.m.
Those rack-mount Milgo units were built like
battleships and very
well regarded in the industry. My first "high-speed" modem was a
Racal/Vadic 3451 that, IIRC, could do 2000 bps when talking to
another 3451 using RV's proprietary protocol.
Vadic had a variant 1200 baud system that wasn't compatible with 212,
too, as I recall.
De
6:28 p.m.
On Jan 31, 2025, at 8:44 PM, Dennis Boone via cctalk
<cctalk(a)classiccmp.org> wrote:
I remember Vadic, though vaguely.
Incidentally, starting with the 212 modem and much more so with higher speed ones, using
"baud" as a synonym for "bits per second" is incorrect. Baud,
correctly used, is signaling units per second. For 103 and 202 modems which just use
plain FSK, the two match. But the 212 uses QPSK, which means it does 1200 bits per second
using 600 baud signaling. And the same, only more so, goes for the more complex
modulation systems of faster modems.
This applies to various modern high speed networks as well. Original Ethernet is one bit
per baud. But that's not true for the higher speed ones.
If you see a link that uses, say, QAM256 coding, you're looking at something that does
8 bits per baud (ignoring any ECC overhead, if the signaling scheme does such a thing).
paul
Those rack-mount Milgo units were built like
battleships and very
well regarded in the industry. My first "high-speed" modem was a
Racal/Vadic 3451 that, IIRC, could do 2000 bps when talking to
another 3451 using RV's proprietary protocol.
Vadic had a variant 1200 baud system that wasn't compatible with 212,
too, as I recall. 
9:17 p.m.
I remember the Vadic modem fondly. In the 1980's, on weekends I'd take home a
terminal and a modem from work, and dial up the Tektronix Information Display
Division's mainframe to play Rogue. However, I think that was 2400 not 1200.
Dave Wise
________________________________
From: Paul Koning via cctalk <cctalk(a)classiccmp.org>
Sent: Saturday, February 1, 2025 10:28 AM
To: cctalk(a)classiccmp.org <cctalk(a)classiccmp.org>
Cc: Paul Koning <paulkoning(a)comcast.net>
Subject: [cctalk] Re: A baudy tale
On Jan 31, 2025, at 8:44 PM, Dennis Boone via cctalk
<cctalk(a)classiccmp.org> wrote:
I remember Vadic, though vaguely.
Incidentally, starting with the 212 modem and much more so with higher speed ones, using
"baud" as a synonym for "bits per second" is incorrect. Baud,
correctly used, is signaling units per second. For 103 and 202 modems which just use
plain FSK, the two match. But the 212 uses QPSK, which means it does 1200 bits per second
using 600 baud signaling. And the same, only more so, goes for the more complex
modulation systems of faster modems.
This applies to various modern high speed networks as well. Original Ethernet is one bit
per baud. But that's not true for the higher speed ones.
If you see a link that uses, say, QAM256 coding, you're looking at something that does
8 bits per baud (ignoring any ECC overhead, if the signaling scheme does such a thing).
paul
Those rack-mount Milgo units were built like
battleships and very
well regarded in the industry. My first "high-speed" modem was a
Racal/Vadic 3451 that, IIRC, could do 2000 bps when talking to
another 3451 using RV's proprietary protocol.
Vadic had a variant 1200 baud system that wasn't compatible with 212,
too, as I recall.
2 Feb
2 Feb
1:11 a.m.
Vadic had a variant 1200 baud system that wasn't
compatible with 212, too, as I recall.
Yup, they did. Can't remember the model number, but I used one of these to dial-in to
work way back then with a Tektronix 4010 DVST graphics terminal. Having 1200 baud that
worked really well over phone lines at a time when most people with home computers were
getting by with 110 or at most 300 baud we great. But, it only worked at 1200 baud
connecting to work. Connecting to BBS's and such maxed out at 300 baud. At least
it was backwards compatible that way. If I remember correctly, it was about 12 inches
deep, about 2 inches tall, and perhaps 8 inches wide, and the front panel had a bunch of
LEDs that indicated all of the normal RS232 signaling lines (CD, CTS, DSR, RTS, DTR, RX
and TX) along with a few that showed the speed (110, 300, or 1200) that it was operating
at. The "screech" it made when connecting up at 1200 baud was very unique
sounding. Much more harsh than 103 FSK signaling, but nothing nearly as complex as the
training that went on when modems started getting up to 9600 baud.
I remember having my first Telebit Trailblazer 9600 baud modem. Reliable 9600 baud over
voice-grade POTS lines. They were very remarkable devices for their time. I used it on
my home Unix system way back when for UUCP connections (for email and USENET) to a number
of local UUCP hubs. The training tones for it were pretty crazy sounding, very unique.
I feel old.
-Rick
1:22 a.m.
On 2/1/25 17:11, Rick Bensene via cctalk wrote:
I remember having my first Telebit Trailblazer 9600
baud modem. Reliable 9600 baud over voice-grade POTS lines. They were very remarkable
devices for their time. I used it on my home Unix system way back when for UUCP
connections (for email and USENET) to a number of local UUCP hubs. The training tones
for it were pretty crazy sounding, very unique.
IIRC the Trailblazer spoofed the UUCP 'g' protocol which resulted in
higher throughput.
I feel old.
You and me both, brother.
Chris
--
Christian Kennedy, Ph.D.
chris(a)mainecoon.com AF6AP | DB00000692 | PG00029419
http://www.mainecoon.com PGP KeyID 108DAB97
PGP fingerprint: 4E99 10B6 7253 B048 6685 6CBC 55E1 20A3 108D AB97
"Mr. McKittrick, after careful consideration…"
4:34 a.m.
They did. I used a Trailblazer myself back in the day. The concept of
super fast transfer in one direction with slow acks in the other was
amazing. I think they could also do Kermit acceleration (which was
pretty cool even with sliding windows).
C
On 2/1/2025 8:22 PM, Christian Kennedy via cctalk wrote:
On 2/1/25 17:11, Rick Bensene via cctalk wrote:
I remember having my first Telebit Trailblazer
9600 baud modem.
Reliable 9600 baud over voice-grade POTS lines. They were very
remarkable devices for their time. I used it on my home Unix system
way back when for UUCP connections (for email and USENET) to a number
of local UUCP hubs. The training tones for it were pretty crazy
sounding, very unique.
IIRC the Trailblazer spoofed the UUCP 'g' protocol
which resulted in
higher throughput.
I feel old.
You and me both, brother.
Chris
4:39 p.m.
Anybody remember Bunker Ramo? Still have one of their two-shoebox-sized
modems somewhere...
On Sat, Feb 1, 2025 at 8:28 PM Rick Bensene via cctalk <
cctalk(a)classiccmp.org> wrote:
Vadic had a variant 1200 baud system that
wasn't compatible with 212,
too, as I recall.
Yup, they did. Can't remember the model number, but I used one of these
to dial-in to work way back then with a Tektronix 4010 DVST graphics
terminal. Having 1200 baud that worked really well over phone lines at a
time when most people with home computers were getting by with 110 or at
most 300 baud we great. But, it only worked at 1200 baud connecting to
work. Connecting to BBS's and such maxed out at 300 baud. At least it
was backwards compatible that way. If I remember correctly, it was about
12 inches deep, about 2 inches tall, and perhaps 8 inches wide, and the
front panel had a bunch of LEDs that indicated all of the normal RS232
signaling lines (CD, CTS, DSR, RTS, DTR, RX and TX) along with a few that
showed the speed (110, 300, or 1200) that it was operating at. The
"screech" it made when connecting up at 1200 baud was very unique
sounding. Much more harsh than 103 FSK signaling, but nothing nearly as
complex as the training that went on when modems started getting up to 9600
baud.
I remember having my first Telebit Trailblazer 9600 baud modem. Reliable
9600 baud over voice-grade POTS lines. They were very remarkable devices
for their time. I used it on my home Unix system way back when for UUCP
connections (for email and USENET) to a number of local UUCP hubs. The
training tones for it were pretty crazy sounding, very unique.
I feel old.
-Rick
1 Feb
1 Feb
12:20 a.m.
Definitely baudy the modem were switch hitters even back then🤣
On 1/31/2025 6:05 PM, Donald Whittemore via cctalk wrote:
In the early 70s my employer used stand alone data
entry tape units in our remote locations. We started with NCR units but then switched to
Tally. In the late afternoon the data would be transmitted to the home office in Chicago
for processing. Also using NCR/Tally units. We used Racal-Milgo modems. These things were
about the size of a large home stereo receiver. We started at 2400 baud. The units could
do 3600 or 4800 (I don’t remember which) if a circuit board strap was moved.
We had locations in many cities/towns all the way out to Montana. It was decided that we
needed to have the ability to switch between 2400 and the faster speed when possible. We
did not want to have the locals power off the modem, open it up, remove a card and move
the strap. So I got volunteered to come up with a plan.
I found a place in the modem where I could mount a switch. Luckily the modem had a
sliding panel on the front so the locals would not have to open the box top. Went to our
fleet garage where they had the tools I needed. I made a bunch of aluminum brackets for a
tiny toggle switch. Added wires to the switch.
It was also decided that we could not trust the locals to do the switch install. So part
of the plan included me going to all the locations and doing the install. I did not have a
car at the time so I got a fleet car. Headed south to Kentucky then turned west. Don’t
remember all the states I hit but I believe the last place I hit on the way home was
Rockford. I remember being on a back road in Montana and I took a picture of my
speedometer. I was doing 65. This was when there was a countrywide speed limit of 55. I
can’t be limited by the Man. :)
Back at the home office we had 6 NCR/Tally machines and only 4 modems. I built a plug
panel box that had everything wired to it and used telephone jack plugs to connect the
Tally’s to an available modem. The box also had switches for the modem speed.
I now forget how long the whole process took. Put my DeVry AAS degree to good use. :)
7:55 p.m.
On 01/02/2025 00:05, Donald Whittemore via cctalk wrote:
Also using NCR/Tally units. We used Racal-Milgo
modems. These things
were about the size of a large home stereo receiver. We started at 2400
baud. The units could do 3600 or 4800 (I don’t remember which) if a
circuit board strap was moved.
Okay, you've got me interested. Was this on a leased line or POTS?
I remember the first 1200bps full duplex modem appearing on my desk
around 1980, and it was exotic. It became more common over the next few
years. But you're talking about ten years earlier than this.
I know Racal Vadic (later Thomson then Thales) made some pretty fast and
expensive gear, but I didn't realise they'd gone above 1200bps until
V.22bis in the 1980s. But that's over POTS - leased line?
9:33 p.m.
On 01/02/2025 00:05, Donald Whittemore via cctalk wrote:
Also using NCR/Tally units. We used Racal-Milgo
modems. These things
were about the size of a large home stereo receiver. We started at 2400
baud. The units could do 3600 or 4800 (I don’t remember which) if a
circuit board strap was moved.
Okay, you've got me interested. Was this on a leased line or POTS?
I remember the first 1200bps full duplex modem appearing on my desk
around 1980, and it was exotic. It became more common over the next few
years. But you're talking about ten years earlier than this.
I know Racal Vadic (later Thomson then Thales) made some pretty fast and
expensive gear, but I didn't realise they'd gone above 1200bps until
V.22bis in the 1980s. But that's over POTS - leased line?
9:35 p.m.
My experience (Tektronix mainframe via Vadic 2400) was POTS, early 1980's.
Dave Wise
________________________________
From: Frank Leonhardt via cctalk <cctalk(a)classiccmp.org>
Sent: Saturday, February 1, 2025 1:33 PM
To: Donald Whittemore via cctalk <cctalk(a)classiccmp.org>
Cc: Frank Leonhardt <classiccmp(a)fjl.co.uk>
Subject: [cctalk] Re: A baudy tale
On 01/02/2025 00:05, Donald Whittemore via cctalk wrote:
Also using NCR/Tally units. We used Racal-Milgo
modems. These things
were about the size of a large home stereo receiver. We started at 2400
baud. The units could do 3600 or 4800 (I don’t remember which) if a
circuit board strap was moved.
Okay, you've got me interested. Was this on a leased line or POTS?
I remember the first 1200bps full duplex modem appearing on my desk
around 1980, and it was exotic. It became more common over the next few
years. But you're talking about ten years earlier than this.
I know Racal Vadic (later Thomson then Thales) made some pretty fast and
expensive gear, but I didn't realise they'd gone above 1200bps until
V.22bis in the 1980s. But that's over POTS - leased line?
2 Feb
2 Feb
1:43 p.m.
On 01/02/2025 21:35, David Wise wrote:
My experience (Tektronix mainframe via Vadic 2400) was POTS, early 1980's.
By the early 1980s V.22 and V.22bis were common (I had a desk full).
This bing in the early 1970s, is what's intriguing me. People with large
budgets had better toys and I want to know about them :-)
32
days inactive
33
days old
15 comments
12 participants
participants (12)
-
Christian Kennedy -
Chuck Guzis -
cz -
David Wise -
Dennis Boone -
Donald Whittemore -
Frank Leonhardt -
Frank Leonhardt -
Mike Katz -
Mike Stein -
Paul Koning -
Rick Bensene