Project

General

Profile

T-View 100 » History » Version 5

manawyrm, 02/18/2022 11:06 PM

1 1 manawyrm
h1. T-View 100
2
3 3 manawyrm
T-View 100 was a video telephone, made by Deutsche Telekom / Siemens.
4 1 manawyrm
5 5 manawyrm
h2. External photos
6
!{width:40%}IMG_3665.JPG! !{width:40%}IMG_3666.JPG!
7
8
Power supply is called STN20, output DC 22.5V; 0.9A. Center positive, 5.5/2.5mm barrel jack.
9
The RCA connectors are (from left to right): Audio out, Video out, Video in, Audio in
10
The purpose for the Mini-DIN port (marked with a computer icon) is currently unknown. It's connected to a MAX202 internally, so probably carries a RS232 serial.
11
12
h2. Internal photos
13 3 manawyrm
14
Video/Interfacing PCB:
15
!{width:40%}IMG_3633.JPG!
16
17
Telephone PCB:
18
!{width:40%}IMG_3644.JPG!
19
20
Display/Camera PCB:
21
!{width:40%}IMG_3656.JPG!
22
23 1 manawyrm
h2. Common faults
24
25
- Faulty display hotbar
26 3 manawyrm
Symptoms: Missing (pixel) rows / columns on the (24x2) character LCD. 
27 1 manawyrm
28
- Faulty capacitors
29
Symptoms: Crashing, low display contrast, flickering LEDs, poor video quality, mains hum on the speakers
30
31
32 3 manawyrm
h2. Phone disassembly
33
34
The bottom cover plate has 6 philips screws and is clipped together at the bottom. Use multiple guitar picks to get them free.
35 2 manawyrm
The plastic does not seem to be brittle (yet), some force is OK.
36
37 1 manawyrm
!{width:40%}IMG_3647.JPG!
38
39
Backside of the main video / interfacing PCB is visible under the cover plate:
40
!{width:40%}IMG_3631.JPG!
41
42 3 manawyrm
Lift the video / interfacing PCB out by pulling it straight up, it's connected via a rigid interface PCB (but not screwed down):
43
!{width:40%}IMG_3634.JPG!
44
45
Unscrew the 7 philips screws attaching the plastic shield. Be careful with the speaker wires on the right, they are not detachable!
46
Lift the plastic shield out of the way to the right. When re-assembling, make sure the hook-mechanism and speaker are correctly in-place.
47
!{width:40%}IMG_3642.JPG!
48 4 manawyrm
49
h2. Display/camera disassembly
50
51
Disassembling the display/camera unit is a bit tricky. You'll need a 10mm socket (and possibly socket extension)!
52
53
Start by removing the 4 screws on the connector: 
54
!{width:40%}IMG_3650.JPG!
55
56
then remove the 3 screws in the top of the unit.
57
The sides of the display/camera unit are covered with round covers. They can be pulled out with a bit of force.
58
!{width:40%}IMG_3652.JPG!
59
60
Use a 10mm socket to unscrew the nuts on both sides.
61
Lift the connector cover. This is tricky! Please fill in a good way to do this. The author broke 2 plastic clips by doing it:
62
!{width:40%}IMG_3653.JPG!
63
64
Remove both bolts (and the washers). The swivel piece can now be bent inwards slightly with a bit of force to get it out.
65
!{width:40%}IMG_3654.JPG!
66
Unscrew the 2 remaining screws holding the display unit together.
67
68
There are clips all around the display/camera unit. Use guitar picks again and open the display. 
Add picture from clipboard (Maximum size: 48.8 MB)