14 Jun
2026
14 Jun
'26
2:34 p.m.
Darn - my beloved Planar ELT320 terminal has died. I was just sitting
there using it and suddenly the screen went blank. The keyboard still works
and the power LED lights, so not a simply power supply failure.
Does anybody have a schematic or service manual for these guys? It's one
of my favorite terminals - not only does it have a beautiful orange/amber EL
display, but it's also way smaller and lighter than any VTxxx terminal of
the era.
Thanks
Bob
14 Jun
14 Jun
2:55 p.m.
On Sun, Jun 14, 2026, 3:34 PM Robert Armstrong via cctalk <
cctalk(a)classiccmp.org> wrote:
Darn - my beloved Planar ELT320 terminal has died.
I was just sitting
there using it and suddenly the screen went blank. The keyboard still
works
and the power LED lights, so not a simply power supply failure.
Does anybody have a schematic or service manual for these guys? It's one
of my favorite terminals - not only does it have a beautiful orange/amber
EL
display, but it's also way smaller and lighter than any VTxxx terminal of
the era.
Thanks
Bob
I also have an ELT320 that failed with a completely dead screen quite a
while ago. I haven't done anything to troubleshoot it yet. My wild guess
without anything to back it up is that maybe a high voltage inverter board
for driving the display died. Maybe I'm lucky and it's just bad capacitors.
I need to open it up again and take another look.
4 p.m.
Yeah – I don’t know much about the ELT320 technology, but if it’s really an
electroluminescent panel then it needs somewhere around 100V of AC to light up the pixels.
There’s a section on the lower left of the PCB that’s clearly some kind of switching power
supply; my guess is that’s a good place to start. But a schematic would be really
(really!) handy.
Bob
From: Glen Slick [mailto:glen.slick@gmail.com]
Sent: Sunday, June 14, 2026 3:55 PM
To: bob(a)jfcl.com; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: [cctalk] Planar ELT320 Schematics?
On Sun, Jun 14, 2026, 3:34 PM Robert Armstrong via cctalk <cctalk(a)classiccmp.org>
wrote:
Darn - my beloved Planar ELT320 terminal has died. I was just sitting
there using it and suddenly the screen went blank. The keyboard still works
and the power LED lights, so not a simply power supply failure.
Does anybody have a schematic or service manual for these guys? It's one
of my favorite terminals - not only does it have a beautiful orange/amber EL
display, but it's also way smaller and lighter than any VTxxx terminal of
the era.
Thanks
Bob
I also have an ELT320 that failed with a completely dead screen quite a while ago. I
haven't done anything to troubleshoot it yet. My wild guess without anything to back
it up is that maybe a high voltage inverter board for driving the display died. Maybe
I'm lucky and it's just bad capacitors. I need to open it up again and take
another look.
16 Jun
16 Jun
5:42 a.m.
Yikes...I have one of those I was counting on using when I finish cleaning
out the lab. A schematic would be good.
KJ
On Sun, Jun 14, 2026 at 8:00 PM Robert Armstrong via cctalk <
cctalk(a)classiccmp.org> wrote:
Yeah – I don’t know much about the ELT320
technology, but if it’s really
an electroluminescent panel then it needs somewhere around 100V of AC to
light up the pixels. There’s a section on the lower left of the PCB that’s
clearly some kind of switching power supply; my guess is that’s a good
place to start. But a schematic would be really (really!) handy.
Bob
From: Glen Slick [mailto:glen.slick@gmail.com]
Sent: Sunday, June 14, 2026 3:55 PM
To: bob(a)jfcl.com; General Discussion: On-Topic and Off-Topic Posts
Subject: Re: [cctalk] Planar ELT320 Schematics?
On Sun, Jun 14, 2026, 3:34 PM Robert Armstrong via cctalk <
cctalk(a)classiccmp.org> wrote:
Darn - my beloved Planar ELT320 terminal has died. I was just sitting
there using it and suddenly the screen went blank. The keyboard still
works
and the power LED lights, so not a simply power supply failure.
Does anybody have a schematic or service manual for these guys? It's one
of my favorite terminals - not only does it have a beautiful orange/amber
EL
display, but it's also way smaller and lighter than any VTxxx terminal of
the era.
Thanks
Bob
I also have an ELT320 that failed with a completely dead screen quite a
while ago. I haven't done anything to troubleshoot it yet. My wild guess
without anything to back it up is that maybe a high voltage inverter board
for driving the display died. Maybe I'm lucky and it's just bad capacitors.
I need to open it up again and take another look.
2:57 p.m.
Here’s my EL display anecdote for you, with best wishes for recovery of your lovely
thing:
My DEC EL display’s screen was dead when I got it. Tried paying very close attention
to its behavior at power-on and noticed very slight arcing somewhere inside the case.
Took it apart and found the arc: a cold solder in what I presumed to be the high volt/high
amp display power path.
Thorough cleaning of the affected parts of arcing residue with CRC QD and stuff brush
and metal pick to scrape. Tiny bit of flux and new solder with fine tip on decent
(Metcal) RF soldering station to be courteously prompt about heat cycle.
Been holding steady for months now with no more arcing and perfect display behavior
once again.
Good luck!
—jake
On Jun 16, 2026, at 09:42, Ken Seefried via cctalk
<cctalk(a)classiccmp.org> wrote:
Yikes...I have one of those I was counting on using when I finish cleaning
out the lab. A schematic would be good.
KJ
> On Sun, Jun 14, 2026 at 8:00 PM Robert Armstrong via cctalk <
> cctalk(a)classiccmp.org> wrote:
>
> Yeah – I don’t know much about the ELT320 technology, but if it’s really
> an electroluminescent panel then it needs somewhere around 100V of AC to
> light up the pixels. There’s a section on the lower left of the PCB that’s
> clearly some kind of switching power supply; my guess is that’s a good
> place to start. But a schematic would be really (really!) handy.
>
>
>
> Bob
>
>
>
> From: Glen Slick [mailto:glen.slick@gmail.com]
> Sent: Sunday, June 14, 2026 3:55 PM
> To: bob(a)jfcl.com; General Discussion: On-Topic and Off-Topic Posts
> Subject: Re: [cctalk] Planar ELT320 Schematics?
>
>
>
> On Sun, Jun 14, 2026, 3:34 PM Robert Armstrong via cctalk <
> cctalk(a)classiccmp.org> wrote:
>
> Darn - my beloved Planar ELT320 terminal has died. I was just sitting
> there using it and suddenly the screen went blank. The keyboard still
> works
> and the power LED lights, so not a simply power supply failure.
>
> Does anybody have a schematic or service manual for these guys? It's one
> of my favorite terminals - not only does it have a beautiful orange/amber
> EL
> display, but it's also way smaller and lighter than any VTxxx terminal of
> the era.
>
>
>
> Thanks
>
> Bob
>
>
>
> I also have an ELT320 that failed with a completely dead screen quite a
> while ago. I haven't done anything to troubleshoot it yet. My wild guess
> without anything to back it up is that maybe a high voltage inverter board
> for driving the display died. Maybe I'm lucky and it's just bad capacitors.
> I need to open it up again and take another look.
>
>
53
days inactive
55
days old
4 comments
4 participants
participants (4)
-
Glen Slick -
Jacob Ritorto -
Ken Seefried -
Robert Armstrong