Post Reply 
Voyager Display Contrast
04-10-2016, 09:05 AM
Post: #1
Voyager Display Contrast
I have an HP-16C which has a slightly lower contrast compared with another HP-16C (or other Voyager calcs). The display background also has a yellow tint. See attachment. I'm wondering what the reason could be. Maybe high exposure to sun light? I could imagine that UV rays might have a bad impact, as they also seem to cause yellowing of calculator and computer cases made of plastic. Any idea?


Attached File(s) Thumbnail(s)
   
Find all posts by this user
Quote this message in a reply
04-10-2016, 09:45 AM
Post: #2
RE: Voyager Display Contrast
These *may* have a different LCD version. We do know that the later Voyagers went from a 2:1 to a 4:1 multiplex LCD that had a slightly lower contrast. See:
https://www.brouhaha.com/~eric/hpcalc/vo...iants.html
Find all posts by this user
Quote this message in a reply
04-10-2016, 09:53 AM
Post: #3
RE: Voyager Display Contrast
It seems to me that early Voyager with small s/n has lower contrast.
(Usually they have flat metal springs, not coiled spring of the battery compartment)
[Image: 10batt.jpg]
Find all posts by this user
Quote this message in a reply
04-10-2016, 10:01 AM
Post: #4
RE: Voyager Display Contrast
(04-10-2016 09:45 AM)Steve Simpkin Wrote:  These *may* have a different LCD version. We do know that the later Voyagers went from a 2:1 to a 4:1 multiplex LCD that had a slightly lower contrast. See:
https://www.brouhaha.com/~eric/hpcalc/vo...iants.html

Ah, thank you for the reference! I didn't knew that. That might indeed be the case with this item as according to the serial no. it was manufactured in 1988. So as with the Series 41 I prefer the earlier models. Improvements with respect to production simplicity are not always improvements in user experience.
Find all posts by this user
Quote this message in a reply
04-10-2016, 01:36 PM
Post: #5
RE: Voyager Display Contrast
Interesting machine variant.

After this, I had a look to my 16C.
To be honest, I can´t see much difference in my two machines, when compared inside house using natural sun light and by direct observation.

Vital data:
HP-15C: Made in USA, s/n: 2241A04786, flat springs battery compartment, year 1982 week 41.
HP-16C: Made in USA, s/n: 2706A14337, coil spring battery compartment,year 1987 week 06.

Both have the same titanium color display bezel, but depending on the angle we look at them, each one can look slightly goodish in comparison with the other.
Very disconcerting!

The 15C LCD have a grey-green background while the 16C is more light-green, independent of light and looking angle conditions.
Both shows display segments in black color with good contrast.

The pictures may not show the real colors due to a low quality Samsung machine I have that tends to saturate the colors.


[Image: HP-16C_15C_comp_002.jpg] [Image: HP-16C_15C_comp_003.jpg]

Jose Mesquita
RadioMuseum.org member

Find all posts by this user
Quote this message in a reply
04-11-2016, 09:34 AM
Post: #6
RE: Voyager Display Contrast
Hi,
It seems to me that the nearest good color is the right side photographie.

Gérard.
Find all posts by this user
Quote this message in a reply
Post Reply 




User(s) browsing this thread: 1 Guest(s)