4 Jul
2023
4 Jul
'23
10:57 p.m.
Hi there - not sure how much overlap there is with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974 (based
on date codes I've found on the motherboard). I'm unable to determine
manufacturer and that would be handy for diagnostic purposes. The terminal
casing is made out of foam, and although there are some serial numbers
stamped around, nothing really lines up. The fans inside have zero dust or
dirt, so I'm thinking this may not have seen much use, or may be a prototype
or pilot for something. It does have RS232 capability. Interestingly the
screen is set down below the keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm safe to
attempt powering up the board (the PSU so far seems to be ok, although some
voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these or
something like it.. any tips would be appreciated. If I can find a manual
I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
5 Jul
5 Jul
1:54 p.m.
Brad,
That's a new one on me.
But the split CRT reminds me of a 1970s IBM desk computer (it was a
computer built into a desk, I forget the model number) and it had a similar
display.
I wonder if this isn't some third-party IBM compatible terminal?
Sellam
On Tue, Jul 4, 2023 at 10:27 PM Brad H via cctalk <cctalk(a)classiccmp.org>
wrote:
Hi there - not sure how much overlap there is with
vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974 (based
on date codes I've found on the motherboard). I'm unable to determine
manufacturer and that would be handy for diagnostic purposes. The terminal
casing is made out of foam, and although there are some serial numbers
stamped around, nothing really lines up. The fans inside have zero dust or
dirt, so I'm thinking this may not have seen much use, or may be a
prototype
or pilot for something. It does have RS232 capability. Interestingly the
screen is set down below the keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm safe
to
attempt powering up the board (the PSU so far seems to be ok, although some
voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these or
something like it.. any tips would be appreciated. If I can find a manual
I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Qkj?usp
=sharing
<https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Qkj?usp=sharing>
Brad
brad(a)techtimetraveller.com
3:25 p.m.
Seems to be RS-232 compatible, which in my experience is unusual for a terminal in the
early half of the 1970s. It has little serial number stickers tucked around but
they're all random numbers, nothing really lines up. A few of the boards have what
appears to be serial numbers in the low hundreds.
So tempting to just plug in and see what happens, but I'm concerned about the voltages
on two pins that seem off.
-----Original Message-----
From: Sellam Abraham via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 6:54 AM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk(a)classiccmp.org>
Cc: Sellam Abraham <sellam.ismail(a)gmail.com>
Subject: [cctalk] Re: 1974 No Name Terminal
Brad,
That's a new one on me.
But the split CRT reminds me of a 1970s IBM desk computer (it was a computer built into a
desk, I forget the model number) and it had a similar display.
I wonder if this isn't some third-party IBM compatible terminal?
Sellam
On Tue, Jul 4, 2023 at 10:27 PM Brad H via cctalk <cctalk(a)classiccmp.org>
wrote:
Hi there - not sure how much overlap there is with
vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based on date codes I've found on the motherboard). I'm unable to
determine manufacturer and that would be handy for diagnostic
purposes. The terminal casing is made out of foam, and although there
are some serial numbers stamped around, nothing really lines up. The
fans inside have zero dust or dirt, so I'm thinking this may not have
seen much use, or may be a prototype or pilot for something. It does
have RS232 capability. Interestingly the screen is set down below the
keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to attempt powering up the board (the PSU so far seems to be ok,
although some voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these
or something like it.. any tips would be appreciated. If I can find a
manual I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Q
kj?usp
=sharing
<https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
Qkj?usp=sharing>
Brad
brad(a)techtimetraveller.com
4:10 p.m.
On 2023-Jul-05, at 8:25 AM, Brad H via cctalk wrote:
Seems to be RS-232 compatible, which in my experience
is unusual for a terminal in the early half of the 1970s. It has little serial number
stickers tucked around but they're all random numbers, nothing really lines up. A few
of the boards have what appears to be serial numbers in the low hundreds.
So tempting to just plug in and see what happens, but I'm concerned about the
voltages on two pins that seem off.
What does 'seem off' mean?
One possibility is they are a floating supply for the CRT heater. Not unusual in those
days was just to have an independent 6.3 or 12.6 VAC secondary on the PS transformer
dedicated to the heater and it often wouldn't be grounded. You could try checking
between the two pins with multimeter ACV range.
This terminal (this specific unit) was mentioned on the list 2 years ago:
https://classiccmp.org/pipermail/cctalk/2021-February/thread.html#57808
2021-Feb-12
Mystery (unusual) 1973 terminal
Around a dozen messages. In one of those messages I list & ref some of the
more-significant ICs from the board photos.
4:45 p.m.
Thank you! I couldn't remember if I'd posted it here before, I've been off
the list for a while.
Because I don't know really anything about it, I'd been operating on the
belief the power sent from the PSU was DC. So maybe that's my issue. There
is a single 10 pin connector from the PSU to the motherboard. I tested for
DC and found the following:
Brown - +5V
Red - +5V
Orange - +5V
Yellow - -16V
Green - +16V
Blue - -0.8V
Purple - GND
Grey - GND
White - GND
Black - -2.4V
I'm not sure if the +16 and -16v need to be adjusted, or if they are that
high because they don't have a load during my testing. The -16V is directly
connected to the VEE on a nearby 1488, and I think the max voltage there
should be -15V.
The blue and black are the ones that didn't seem right. But, if they're not
DC then maybe that's my issue. Also last night I found more cold solder
joints, so maybe one or both are affected by that. I will test with my DMM
as AC instead of DC and see if I get something there instead. Barring that,
I'm working on a schematic of the PSU to try and figure out what it's
supposed to be delivering.
Like I said, very tempting to plug in, I suspect it may be just fine.. but..
there's a lot of chips to blow up here if I'm wrong.
-----Original Message-----
From: Brent Hilpert via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 9:11 AM
To: General Discussion: On-Topic and Off-Topic Posts <cctalk(a)classiccmp.org>
Cc: Brent Hilpert <bhilpert(a)shaw.ca>
Subject: [cctalk] Re: 1974 No Name Terminal
On 2023-Jul-05, at 8:25 AM, Brad H via cctalk wrote:
Seems to be RS-232 compatible, which in my experience
is unusual for a
terminal in the early half of the 1970s. It has little serial
number
stickers tucked around but they're all random numbers, nothing really lines
up. A few of the boards have what appears to be serial numbers in the low
hundreds.
So tempting to just plug in and see what happens, but I'm concerned about
the
voltages on two pins that seem off.
What does 'seem off' mean?
One possibility is they are a floating supply for the CRT heater. Not
unusual in those days was just to have an independent 6.3 or 12.6 VAC
secondary on the PS transformer dedicated to the heater and it often
wouldn't be grounded. You could try checking between the two pins with
multimeter ACV range.
This terminal (this specific unit) was mentioned on the list 2 years ago:
https://classiccmp.org/pipermail/cctalk/2021-February/thread.html#57808
2021-Feb-12
Mystery (unusual) 1973 terminal
Around a dozen messages. In one of those messages I list & ref some of the
more-significant ICs from the board photos.
10:08 p.m.
On 2023-Jul-05, at 9:45 AM, <brad(a)techtimetraveller.com>
<brad(a)techtimetraveller.com> wrote:
Thank you! I couldn't remember if I'd posted
it here before, I've been off
the list for a while.
Because I don't know really anything about it, I'd been operating on the
belief the power sent from the PSU was DC. So maybe that's my issue. There
is a single 10 pin connector from the PSU to the motherboard. I tested for
DC and found the following:
Brown - +5V
Red - +5V
Orange - +5V
Yellow - -16V
Green - +16V
Blue - -0.8V
Purple - GND
Grey - GND
White - GND
Black - -2.4V
I'm not sure if the +16 and -16v need to be adjusted, or if they are that
high because they don't have a load during my testing. The -16V is directly
connected to the VEE on a nearby 1488, and I think the max voltage there
should be -15V.
The blue and black are the ones that didn't seem right. But, if they're not
DC then maybe that's my issue. Also last night I found more cold solder
joints, so maybe one or both are affected by that. I will test with my DMM
as AC instead of DC and see if I get something there instead. Barring that,
I'm working on a schematic of the PSU to try and figure out what it's
supposed to be delivering.
Like I said, very tempting to plug in, I suspect it may be just fine.. but..
there's a lot of chips to blow up here if I'm wrong.
Seeing as how you're looking at the connections from the PS to the logic, raises the
question of how the monitor is being powered: does it have it's own PS from 120VAC,
wired to the PS directly, or from the PS via the logic board.
Some points about supplies:
- The memory chips are 1402 256*4 PMOS shift registers. These need supplies of Vcc = +5
and Vdd = -5 to -9V.
The 1402s also need higher voltage clock signals, between Vcc-15 and Vcc-17 (may be -10
to -12 relative to gnd).
The two MMH0026 ICs beside the 1402s are the clock drivers for the 1402s.
- The 3258 character generator needs -12 (and +5).
- The 1602 UART probably needs -12 (and +5).
- The RS232 needs +something and -something line-drive levels of course.
- There's what looks to be a potted crystal clock module on there, might check what
its supply is.
Could be +5, but could be something else.
- There's probably a MOS keyboard encoder that may require some supplies besides just
+5.
- Some of these supplies may be derived via components (e.g. zener & dropping R) on
the logic boards.
- And of course the monitor needs its supply(s).
Seeing as how you have some odd things appearing on the PS, if it were me, I would be:
- RE-ing the PS thoroughly,
- figuring out the power connections on the logic boards to these special ICs,
- figuring out the monitor power supply/sources
.. so it's known how all these requirements are intended to be met before powering the
whole thing up.
I recently refurbished a Teleray terminal from the same period. It uses MOS shift
registers from the same family (1404s) and similar funky clock drivers. The power supplies
design was more straightforward than what you appear to be dealing with. On things like
this I also like to look at the DB25 connector to see exactly how it's wired -
fixed-level ctl-sig outputs, connections for ctl-sig inputs that may be required, DCE vs
DTE, whether there are any non-EIA-standard connections present.
3:28 p.m.
At first glance it reminded me of the Hazeltine 1000, I owned one in the
early 1980's. Brutally simple terminals, I remember getting a ROM from
Jameco which allowed the terminal to display lowercase letters. Pure
luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is with
vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974 (based
on date codes I've found on the motherboard). I'm unable to determine
manufacturer and that would be handy for diagnostic purposes. The terminal
casing is made out of foam, and although there are some serial numbers
stamped around, nothing really lines up. The fans inside have zero dust or
dirt, so I'm thinking this may not have seen much use, or may be a prototype
or pilot for something. It does have RS232 capability. Interestingly the
screen is set down below the keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm safe to
attempt powering up the board (the PSU so far seems to be ok, although some
voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these or
something like it.. any tips would be appreciated. If I can find a manual
I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
6 Jul
6 Jul
9:54 p.m.
I worked on VDU's as an engineer in the UK before joining DEC to sell
volume VT100's in 1975
There's a mention of block on one of the cards so a block mode terminal.
That means enter data and press a key to send the lot.
The card cage could mean its emulating something.
I'd test as many capacitors as possible. PSU first and replace as required.
Run PSU and check voltages.
Check each board for power rail to ground shorts.
If ok give each board +5v on its own and see if the TTL is alive.
If theres a clock gen start there (look for a crystal can)
Loads of fans might indicate an industrial environment
At this age some TTL will have failed plus capacitors.
Rod Smallwood
On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
At first glance it reminded me of the Hazeltine 1000,
I owned one in
the early 1980's. Brutally simple terminals, I remember getting a ROM
from Jameco which allowed the terminal to display lowercase letters.
Pure luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is
with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based
on date codes I've found on the motherboard). I'm unable to determine
manufacturer and that would be handy for diagnostic purposes. The
terminal
casing is made out of foam, and although there are some serial numbers
stamped around, nothing really lines up. The fans inside have zero
dust or
dirt, so I'm thinking this may not have seen much use, or may be a
prototype
or pilot for something. It does have RS232 capability. Interestingly
the
screen is set down below the keyboard so that only half of it is
visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to
attempt powering up the board (the PSU so far seems to be ok,
although some
voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these or
something like it.. any tips would be appreciated. If I can find a
manual
I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
10:12 p.m.
Thanks Rod!
I discovered an immediate problem I hadn't caught before.. two of the trimmer
resistors had actually been broken right off two of their legs.. so that may account for
strange/missing voltages. They are a CONRAC part 928237. The CRT is CONRAC too, but I
still don't think this is a CONRAC terminal. Anyway, I only found one source for the
exact resistor, an aerospace company, and they want $80 per unit (I think they just want
me to go away).
So far in testing I haven't found any shorts. My main worry is the PSU sending
incorrect voltages to wrong place. In addition to the broken resistors I also discovered
some broken solder joints on the PSU PCB.. those at least are repaired. I'm trying to
figure out the resistance the two resistors were set to so I can put a replacement in with
same, hopefully that gets me close to what should be there.
Brad
-----Original Message-----
From: Rod Smallwood via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 8:48 AM
To: Douglas Taylor via cctalk <cctalk(a)classiccmp.org>
Cc: Rod Smallwood <rodsmallwood52(a)btinternet.com>
Subject: [cctalk] Re: 1974 No Name Terminal
I worked on VDU's as an engineer in the UK before joining DEC to sell volume
VT100's in 1975
There's a mention of block on one of the cards so a block mode terminal.
That means enter data and press a key to send the lot.
The card cage could mean its emulating something.
I'd test as many capacitors as possible. PSU first and replace as required.
Run PSU and check voltages.
Check each board for power rail to ground shorts.
If ok give each board +5v on its own and see if the TTL is alive.
If theres a clock gen start there (look for a crystal can)
Loads of fans might indicate an industrial environment
At this age some TTL will have failed plus capacitors.
Rod Smallwood
On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
At first glance it reminded me of the Hazeltine 1000,
I owned one in
the early 1980's. Brutally simple terminals, I remember getting a ROM
from Jameco which allowed the terminal to display lowercase letters.
Pure luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is
with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based on date codes I've found on the motherboard). I'm unable to
determine manufacturer and that would be handy for diagnostic
purposes. The terminal casing is made out of foam, and although there
are some serial numbers stamped around, nothing really lines up. The
fans inside have zero dust or dirt, so I'm thinking this may not have
seen much use, or may be a prototype or pilot for something. It does
have RS232 capability. Interestingly the screen is set down below the
keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to attempt powering up the board (the PSU so far seems to be ok,
although some voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these
or something like it.. any tips would be appreciated. If I can find a
manual I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
11:15 p.m.
I’ve just pressed the 2 broken end together and measured the resistance end to end to get
an idea of the resistance. Any old trimmer of suitable value should work as a replacement
as the vdu is probably not going to be in a harsh environment anymore.
Sent from my iPhone
On Jul 6, 2023, at 15:13, Brad H via cctalk
<cctalk(a)classiccmp.org> wrote:
Thanks Rod!
I discovered an immediate problem I hadn't caught before.. two of the trimmer
resistors had actually been broken right off two of their legs.. so that may account for
strange/missing voltages. They are a CONRAC part 928237. The CRT is CONRAC too, but I
still don't think this is a CONRAC terminal. Anyway, I only found one source for the
exact resistor, an aerospace company, and they want $80 per unit (I think they just want
me to go away).
So far in testing I haven't found any shorts. My main worry is the PSU sending
incorrect voltages to wrong place. In addition to the broken resistors I also discovered
some broken solder joints on the PSU PCB.. those at least are repaired. I'm trying to
figure out the resistance the two resistors were set to so I can put a replacement in with
same, hopefully that gets me close to what should be there.
Brad
-----Original Message-----
From: Rod Smallwood via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 8:48 AM
To: Douglas Taylor via cctalk <cctalk(a)classiccmp.org>
Cc: Rod Smallwood <rodsmallwood52(a)btinternet.com>
Subject: [cctalk] Re: 1974 No Name Terminal
I worked on VDU's as an engineer in the UK before joining DEC to sell volume
VT100's in 1975
There's a mention of block on one of the cards so a block mode terminal.
That means enter data and press a key to send the lot.
The card cage could mean its emulating something.
I'd test as many capacitors as possible. PSU first and replace as required.
Run PSU and check voltages.
Check each board for power rail to ground shorts.
If ok give each board +5v on its own and see if the TTL is alive.
If theres a clock gen start there (look for a crystal can)
Loads of fans might indicate an industrial environment
At this age some TTL will have failed plus capacitors.
Rod Smallwood
On 05/07/2023 16:28, Douglas Taylor via cctalk
wrote:
At first glance it reminded me of the Hazeltine 1000, I owned one in
the early 1980's. Brutally simple terminals, I remember getting a ROM
from Jameco which allowed the terminal to display lowercase letters.
Pure luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based on date codes I've found on the motherboard). I'm unable to
determine manufacturer and that would be handy for diagnostic
purposes. The terminal casing is made out of foam, and although there
are some serial numbers stamped around, nothing really lines up. The
fans inside have zero dust or dirt, so I'm thinking this may not have
seen much use, or may be a prototype or pilot for something. It does
have RS232 capability. Interestingly the screen is set down below the
keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to attempt powering up the board (the PSU so far seems to be ok,
although some voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these
or something like it.. any tips would be appreciated. If I can find a
manual I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
7 Jul
7 Jul
2:40 a.m.
Conrac mainly made CRT monitor assemblies, so the actual terminal was quite
possibly made by someone else.
It looks vaguely familiar; I'm surprised no one's recognized it.
m
On Thu, Jul 6, 2023 at 6:13 PM Brad H via cctalk <cctalk(a)classiccmp.org>
wrote:
Thanks Rod!
I discovered an immediate problem I hadn't caught before.. two of the
trimmer resistors had actually been broken right off two of their legs.. so
that may account for strange/missing voltages. They are a CONRAC part
928237. The CRT is CONRAC too, but I still don't think this is a CONRAC
terminal. Anyway, I only found one source for the exact resistor, an
aerospace company, and they want $80 per unit (I think they just want me to
go away).
So far in testing I haven't found any shorts. My main worry is the PSU
sending incorrect voltages to wrong place. In addition to the broken
resistors I also discovered some broken solder joints on the PSU PCB..
those at least are repaired. I'm trying to figure out the resistance the
two resistors were set to so I can put a replacement in with same,
hopefully that gets me close to what should be there.
Brad
-----Original Message-----
From: Rod Smallwood via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 8:48 AM
To: Douglas Taylor via cctalk <cctalk(a)classiccmp.org>
Cc: Rod Smallwood <rodsmallwood52(a)btinternet.com>
Subject: [cctalk] Re: 1974 No Name Terminal
I worked on VDU's as an engineer in the UK before joining DEC to sell
volume VT100's in 1975
There's a mention of block on one of the cards so a block mode terminal.
That means enter data and press a key to send the lot.
The card cage could mean its emulating something.
I'd test as many capacitors as possible. PSU first and replace as required.
Run PSU and check voltages.
Check each board for power rail to ground shorts.
If ok give each board +5v on its own and see if the TTL is alive.
If theres a clock gen start there (look for a crystal can)
Loads of fans might indicate an industrial environment
At this age some TTL will have failed plus capacitors.
Rod Smallwood
On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
At first glance it reminded me of the Hazeltine
1000, I owned one in
the early 1980's. Brutally simple terminals, I remember getting a ROM
from Jameco which allowed the terminal to display lowercase letters.
Pure luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is
with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based on date codes I've found on the motherboard). I'm unable to
determine manufacturer and that would be handy for diagnostic
purposes. The terminal casing is made out of foam, and although there
are some serial numbers stamped around, nothing really lines up. The
fans inside have zero dust or dirt, so I'm thinking this may not have
seen much use, or may be a prototype or pilot for something. It does
have RS232 capability. Interestingly the screen is set down below the
keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to attempt powering up the board (the PSU so far seems to be ok,
although some voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these
or something like it.. any tips would be appreciated. If I can find a
manual I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
3:17 a.m.
On Thu, Jul 6, 2023, 8:41 PM Mike Stein via cctalk <cctalk(a)classiccmp.org>
wrote:
Conrac mainly made CRT monitor assemblies, so the
actual terminal was quite
possibly made by someone else.
It looks vaguely familiar; I'm surprised no one's recognized it.
Yea. Looks vaguely SABER like, but my only experience with them is airline
tickets an eon ago... but the screen looks all wrong...
Warner
m
On Thu, Jul 6, 2023 at 6:13 PM Brad H via cctalk <cctalk(a)classiccmp.org>
wrote:
Thanks Rod!
I discovered an immediate problem I hadn't caught before.. two of the
trimmer resistors had actually been broken right off two of their legs..
so
that may account for strange/missing voltages.
They are a CONRAC part
928237. The CRT is CONRAC too, but I still don't think this is a CONRAC
terminal. Anyway, I only found one source for the exact resistor, an
aerospace company, and they want $80 per unit (I think they just want me
to
go away).
So far in testing I haven't found any shorts. My main worry is the PSU
sending incorrect voltages to wrong place. In addition to the broken
resistors I also discovered some broken solder joints on the PSU PCB..
those at least are repaired. I'm trying to figure out the resistance the
two resistors were set to so I can put a replacement in with same,
hopefully that gets me close to what should be there.
Brad
-----Original Message-----
From: Rod Smallwood via cctalk <cctalk(a)classiccmp.org>
Sent: Wednesday, July 5, 2023 8:48 AM
To: Douglas Taylor via cctalk <cctalk(a)classiccmp.org>
Cc: Rod Smallwood <rodsmallwood52(a)btinternet.com>
Subject: [cctalk] Re: 1974 No Name Terminal
I worked on VDU's as an engineer in the UK before joining DEC to sell
volume VT100's in 1975
There's a mention of block on one of the cards so a block mode terminal.
That means enter data and press a key to send the lot.
The card cage could mean its emulating something.
I'd test as many capacitors as possible. PSU first and replace as
required.
Run PSU and check voltages.
Check each board for power rail to ground shorts.
If ok give each board +5v on its own and see if the TTL is alive.
If theres a clock gen start there (look for a crystal can)
Loads of fans might indicate an industrial environment
At this age some TTL will have failed plus capacitors.
Rod Smallwood
On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
At first glance it reminded me of the Hazeltine
1000, I owned one in
the early 1980's. Brutally simple terminals, I remember getting a ROM
from Jameco which allowed the terminal to display lowercase letters.
Pure luxury.
Doug
On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
Hi there - not sure how much overlap there is
with vcfed's forum, but
thought I would reach out here in case. I have a terminal from 1974
(based on date codes I've found on the motherboard). I'm unable to
determine manufacturer and that would be handy for diagnostic
purposes. The terminal casing is made out of foam, and although there
are some serial numbers stamped around, nothing really lines up. The
fans inside have zero dust or dirt, so I'm thinking this may not have
seen much use, or may be a prototype or pilot for something. It does
have RS232 capability. Interestingly the screen is set down below the
keyboard so that only half of it is visible.
My main issue right now is the PSU - I am trying to determine if I'm
safe to attempt powering up the board (the PSU so far seems to be ok,
although some voltages on a couple of pins are mysterious).
Anyway, on the extremely off chance anyone has ever seen one of these
or something like it.. any tips would be appreciated. If I can find a
manual I'll feel a lot safer about turning it on.
Some pics here:
https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
Qkj?usp
=sharing
Brad
brad(a)techtimetraveller.com
6:39 a.m.
OK time to look at what we dont see.
No numeric pad
No function keys
Keys with blank tops (dummies?)
Pretty much a 'glass teletype'
Not untypical of a general use terminal in a college or university.
Rod Smallwood
On 07/07/2023 04:17, Warner Losh via cctalk wrote:
On Thu, Jul 6, 2023, 8:41 PM Mike Stein via cctalk
<cctalk(a)classiccmp.org>
wrote:
Conrac mainly made CRT monitor assemblies, so the
actual terminal was quite
possibly made by someone else.
It looks vaguely familiar; I'm surprised no one's recognized it.
Yea. Looks vaguely SABER like, but my only experience with them is airline
tickets an eon ago... but the screen looks all wrong...
Warner
m
> On Thu, Jul 6, 2023 at 6:13 PM Brad H via cctalk <cctalk(a)classiccmp.org>
> wrote:
>
>> Thanks Rod!
>>
>> I discovered an immediate problem I hadn't caught before.. two of the
>> trimmer resistors had actually been broken right off two of their legs..
> so
>> that may account for strange/missing voltages. They are a CONRAC part
>> 928237. The CRT is CONRAC too, but I still don't think this is a CONRAC
>> terminal. Anyway, I only found one source for the exact resistor, an
>> aerospace company, and they want $80 per unit (I think they just want me
> to
>> go away).
>>
>> So far in testing I haven't found any shorts. My main worry is the PSU
>> sending incorrect voltages to wrong place. In addition to the broken
>> resistors I also discovered some broken solder joints on the PSU PCB..
>> those at least are repaired. I'm trying to figure out the resistance the
>> two resistors were set to so I can put a replacement in with same,
>> hopefully that gets me close to what should be there.
>>
>> Brad
>>
>> -----Original Message-----
>> From: Rod Smallwood via cctalk <cctalk(a)classiccmp.org>
>> Sent: Wednesday, July 5, 2023 8:48 AM
>> To: Douglas Taylor via cctalk <cctalk(a)classiccmp.org>
>> Cc: Rod Smallwood <rodsmallwood52(a)btinternet.com>
>> Subject: [cctalk] Re: 1974 No Name Terminal
>>
>> I worked on VDU's as an engineer in the UK before joining DEC to sell
>> volume VT100's in 1975
>>
>> There's a mention of block on one of the cards so a block mode terminal.
>>
>> That means enter data and press a key to send the lot.
>>
>> The card cage could mean its emulating something.
>>
>> I'd test as many capacitors as possible. PSU first and replace as
> required.
>> Run PSU and check voltages.
>>
>> Check each board for power rail to ground shorts.
>>
>> If ok give each board +5v on its own and see if the TTL is alive.
>>
>> If theres a clock gen start there (look for a crystal can)
>>
>> Loads of fans might indicate an industrial environment
>>
>> At this age some TTL will have failed plus capacitors.
>>
>> Rod Smallwood
>>
>>
>> On 05/07/2023 16:28, Douglas Taylor via cctalk wrote:
>>> At first glance it reminded me of the Hazeltine 1000, I owned one in
>>> the early 1980's. Brutally simple terminals, I remember getting a ROM
>>> from Jameco which allowed the terminal to display lowercase letters.
>>> Pure luxury.
>>> Doug
>>>
>>> On 7/4/2023 6:57 PM, Brad H via cctalk wrote:
>>>> Hi there - not sure how much overlap there is with vcfed's forum,
but
>>>> thought I would reach out here in case. I have a terminal from 1974
>>>> (based on date codes I've found on the motherboard). I'm unable
to
>>>> determine manufacturer and that would be handy for diagnostic
>>>> purposes. The terminal casing is made out of foam, and although there
>>>> are some serial numbers stamped around, nothing really lines up. The
>>>> fans inside have zero dust or dirt, so I'm thinking this may not
have
>>>> seen much use, or may be a prototype or pilot for something. It does
>>>> have RS232 capability. Interestingly the screen is set down below the
>>>> keyboard so that only half of it is visible.
>>>>
>>>>
>>>> My main issue right now is the PSU - I am trying to determine if I'm
>>>> safe to attempt powering up the board (the PSU so far seems to be ok,
>>>> although some voltages on a couple of pins are mysterious).
>>>>
>>>>
>>>> Anyway, on the extremely off chance anyone has ever seen one of these
>>>> or something like it.. any tips would be appreciated. If I can find a
>>>> manual I'll feel a lot safer about turning it on.
>>>>
>>>>
>>>> Some pics here:
>>>> https://drive.google.com/drive/folders/1-2uEFbi3OKBYr06y6yHnygDiLMtw2
>>>> Qkj?usp
>>>>
>>>> =sharing
>>>>
>>>>
>>>> Brad
>>>>
>>>> brad(a)techtimetraveller.com
>>>>
>>>>
>>
515
days inactive
518
days old
12 comments
8 participants
participants (8)
-
brad＠techtimetraveller.com -
Brent Hilpert -
Douglas Taylor -
Mike Stein -
Rod Smallwood -
Sellam Abraham -
Warner Losh -
Wayne S