Tek 1503C TDR


warren.stirling@...
 

Hi all,

Does anyone, by faint chance, have a replacement lcd assembly for a 1503C TDR?


Dale H. Cook
 

Good luck - failure of the LCD is a frequent problem in the 1502/1503 A/B/C TDRs. That is why I own a 1503 (as Scotty said in the NextGen episode "Relics", "No bloody A, B, C, or D").

Dale H. Cook, GR/HP/Tek Collector, Roanoke/Lynchburg, VA
https://plymouthcolony.net/starcity/radios/


 

Judging by the pictures on TekWiki those LCD displays could use replacing even when they were "working."

It looks like the LCD is getting 8-bit parallel data from the CPU with 3 address lines and read and write strobes. The display modules are only referenced using Tek part numbers (672-1241-00 below SN B023854, 118-9050-01 after), but I wonder how hard it would be to decipher that protocol. At the very least you could read the Z-80 assembly that generates the video output straight out of the ROMs.

That would be a lot easier to read with a modern LCD and backlight, or a nice, old-school gas plasma or vacuum fluorescent display.

-- Jeff Dutky


Harvey White
 

In one of the TM5000 series function generators with an LCD display, I was able to replace the Tek display (with an EL backlight) with a standard 2 line x 16 character off the shelf LCD display.  The two displays looked physically identical with the exception of the EL backlight, of course.

Harvey

On 4/26/2021 11:44 AM, Jeff Dutky wrote:
Judging by the pictures on TekWiki those LCD displays could use replacing even when they were "working."

It looks like the LCD is getting 8-bit parallel data from the CPU with 3 address lines and read and write strobes. The display modules are only referenced using Tek part numbers (672-1241-00 below SN B023854, 118-9050-01 after), but I wonder how hard it would be to decipher that protocol. At the very least you could read the Z-80 assembly that generates the video output straight out of the ROMs.

That would be a lot easier to read with a modern LCD and backlight, or a nice, old-school gas plasma or vacuum fluorescent display.

-- Jeff Dutky





Paul Amaranth
 

Someone on eevblog replaced the lcd screen on a 1502B with an LCD panel:

https://www.eevblog.com/forum/repair/tek-1502b-tdr-restoration-project-and-more/msg3555459/#msg3555459

Some useful info there.

Paul

On Mon, Apr 26, 2021 at 01:08:05PM -0400, Harvey White wrote:
In one of the TM5000 series function generators with an LCD display, I was
able to replace the Tek display (with an EL backlight) with a standard 2
line x 16 character off the shelf LCD display.  The two displays looked
physically identical with the exception of the EL backlight, of course.

Harvey


On 4/26/2021 11:44 AM, Jeff Dutky wrote:
Judging by the pictures on TekWiki those LCD displays could use replacing even when they were "working."

It looks like the LCD is getting 8-bit parallel data from the CPU with 3 address lines and read and write strobes. The display modules are only referenced using Tek part numbers (672-1241-00 below SN B023854, 118-9050-01 after), but I wonder how hard it would be to decipher that protocol. At the very least you could read the Z-80 assembly that generates the video output straight out of the ROMs.

That would be a lot easier to read with a modern LCD and backlight, or a nice, old-school gas plasma or vacuum fluorescent display.

-- Jeff Dutky
--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@AuroraGrp.Com | Unix/Linux - We don't do windows


 

On Mon, Apr 26, 2021 at 01:36 AM, <warren.stirling@bigpond.com> wrote:


Does anyone, by faint chance, have a replacement lcd assembly for a 1503C TDR?
If it's just failed backlights, like in my 1502B and 1503C: I replaced both electroluminescence foils with foils sold by some car accessory shops, intended to brighten up dashboard speed and RPM scales and the like.

Raymond


 

On Tue, Apr 27, 2021 at 12:46 AM, Raymond Domp Frank wrote:


like in my 1502B and 1503C
That's 1502C and 1503B, FWIW...

Raymond


romeo987
 

I had a problem with my display recently, and in my research gleaned that they are rare. However, I managed to repair mine - a relatively simple problem with an elastomeric connector. But your fault may be quite different from mine.
There is a long thread over on eevblog on this topic (in the repair section - if I was more savvy, or sitting at my desktop, I would add a link). A number of people have fabricated ‘modern’ replacements.
Happy to talk more if you think repair is an option for you...
Roman


warren.stirling@...
 

Hi all,

As a first timer here, I thank you for your replies. The enquiry was on behalf of a friend who has a 1503c with a cracked screen, so replacement is his only option.

I'll follow up the links that have been posted, there may be a solution to be found...

For myself I've one point five 1503 with crts in them (one only half works and will be kept as spares if I can't resurrect it - it's been 'modified' shall we say...

Old technology never dies, the repairs just get newer