Re: Looking for data on 1980s CDS cells - VACTEK VT212/VT212L (SOLVED).

On 2024-09-11 2:15 p.m., Phil Hobbs wrote:

On 2024-09-10 01:55, John Robertson wrote:

On 2024-09-09 9:33 p.m., Chris Jones wrote:

On 29/08/2024 10:19 am, John Robertson wrote:

I'm trying to find a modern CDS cells to replace these old timers
(1982) from the 70s, I did find a catalogue page for these CDS
cells, but the details are not as useful to me as perhaps they would
be to someone handy with using CDS cells.

The ratings are:
VT212L - 6 R1, 5 R2
VT212  - 7.8 R1, 5 R2

R1 defined as 2fc resistance in K Ohms (tolerance +/- 33.3% @ 2850K
Source
R2 defined as min dark resistance (Megohms) in 5 sec.

Having a heck of a time matching these to more modern cds such as
carried by DK or Mouser. I tried the NSL-06S53, but its light
resistance is too sensitive and nothing else on DK was better.

Anyone have a VACTEK catalogue who could scan the pages that might
help?

I suspect that PerkinElmer bought out Vactek as they used similar
part (VT200x) numbers as early as 2001 that I could find on
web.archive.org, but that archive doesn't have the parts books
captured.

Bitsavers doesn't list it, nothing on ebay either...

Why am I bothering? I have a rifle gallery (http://
www.bonanzagallery.com/) that uses flash tubes in the rifles to trip
the cds cells in the targets and there are around 70 cds cells. A
number of them are failing so I want to replace them with something
that will work reliably.

Thanks as always for your time!

John :-#)#

Did you see ths document?:

https://www.worldradiohistory.com/Archive-Tele-Tech/60s/Electronic-
Industries-1965-07.pdf

Page 84/85 of the pdf, or page 82/83 printed on the original.

It says
Type VT212
CdSe material
0.62 - 0.86 micron spectral limits (10% points)
0.74 micron peak sensitivity
0.21 inch diameter
0.146 inch depth
 >0.5Meg dark resistance, 25 deg C
7.8kOhm at 2 ft-c T 2850K
50mW dissipation
70 Volt rating
at 0.1 ft-c resistance is 67% of room temperature resistance at 65 deg C
6ms rise time, 5ms decay time at 10 ft-c

Thanks!

John :-#)#

I have a 1988 Clairex catalog that cross-references the VT212 and VT212L
to a Clairex CL903L, which is

6k +- 2k ohms @ 2 footcandles, 40M dark, 100VAC (peak), TO18 case.

Cheers

Phil Hobbs

Thanks all, I think I have enough information now.

John :-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
                      John's Jukes Ltd.
        #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
          (604)872-5757 (Pinballs, Jukes, Video Games)
                      www.flippers.com
        "Old pinballers never die, they just flip out."