Today I checked all the CCD cables which is connected input channels of the VIDEOMUX.
Among total 25 cables for output, 12 cables are type of RG59, 4 cables are type of RG58, and 9 cables are of unknown type.
The reason I am checking the cables is for replacing the cables with impedance of 50 or 52 ohm by those with impedance of 75 ohm.
After I figures out which cable has not proper impedance, I will make new cables and substitute them in order to match the impedance, which would lead to better VIDEO signal.
Today, I check the cables in similar way as I did the last time.
I labeled all cables connected to input channels of VIDEO MUX and disconnect all of them since last time it was hard to check every cable because of cables too entangled.
Then I checked the types of all cables and existing label which might designate where each cable is connected to.
After I finished the check, I reconnected all cables into the input channel which each of cable was connected to before I disconnected.
4 cables out of 25 are type of RG58 so expected to be replace with cable of type RG59.
9 cables out of 25 are of unknown type. These nine cables are all orange-colored thick cables which do not have any label about the cable characteristic on the surface.
The result of observation is as follows.
Note that type 'TBD-1' is used for the orange colored cables because all of them look like the same type of cable.
Channel number |
where its signal is coming |
type |
1 |
C1:IO-VIDEO 1 MC2 |
TBD-1 |
2 |
FI CAMERA |
59 |
3 |
PSL OUTPUT CAMERA |
59 |
4 |
BS C:1O-VIDEO 4 |
TBD-1 |
5 |
MC1&3 C:1O-VIDEO 5 |
59 |
6 |
ITMX C:1O-VIDEO 6 |
TBD-1 |
7 |
C1:IO-VIDEO 7 ITMY |
TBD-1 |
8 |
C1:IO-VIDEO 8 ETMX |
TBD-1 |
9 |
C1:IO-VIDEO 9 ETMY |
TBD-1 |
10 |
No cable is connected
(spare channel) |
|
11 |
C1:IO-VIDEO 11 RCR |
59 |
12 |
C1:IO-VIDEO RCT |
59 |
13 |
MCR VIDEO |
59 |
14 |
C1:IO-VIDEO 14 PMCT |
59 |
15 |
VIDEO 15 PSL IOO(OR IOC) |
59 |
16 |
C1:IO-VIDEO 16 IMCT |
TBD-1 |
17 |
PSL CAMERA |
58 |
18 |
C1:IO-VIDEO 18 IMCR |
59 |
19 |
C1:IO-VIDEO 19 SPS |
59 |
20 |
C1:IO-VIDEO 20 BSPO |
TBD-1 |
21 |
C1:IO-VIDEO 21 ITMXPO |
TBD-1 |
22 |
C1:IO-VIDEO 22 APS1 |
59 |
23 |
ETMX-T |
58 |
24 |
ETMY-T |
58 |
25 |
POY CCD VIDEO CH25 |
58 |
26 |
OMC-V |
59 |
|
Today I could not figure out what impedance the TBD-1 type(unknown type) has.
Next time, I will check out the orange-colored cables' impedance directly and find where the unknown output signal is sent. Any suggestion would be really appreciated. |