| Title: | DEChub/HUBwatch/PROBEwatch CONFERENCE |
| Notice: | Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7 |
| Moderator: | NETCAD::COLELLA DT |
| Created: | Wed Nov 13 1991 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 4455 |
| Total number of notes: | 16761 |
Does anyone know what the power loss in dB is for MIC connectors? Any
info on power budgets in our FDDI equipment would also be appreciated.
(Cross posted in FDDI)
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 2257.1 | NETCAD::B_CRONIN | Tue May 09 1995 10:27 | 3 | ||
The loss budget is 11 dB for multimode fiber. The MIC itself is
not specified for loss. Only the plug to plug loss is specified.
| |||||
| 2257.2 | But I'm still not sure | SNOFS1::KHOOJEANNIE | Tue May 09 1995 21:32 | 8 | |
The 11dB is the maximum attenuation permitted in the FDDI standard isn't
it?
I wanted to find out the actual loss in dB for a MIC connector (e.g. 2dB or
whatever), so that this can be used to calculate whether a particular
implementation stays within the 11dB limit end-to-end.
Can you help with this?
| |||||
| 2257.3 | Some information and guidelines | NPSS::KIRK | Wed May 10 1995 09:34 | 22 | |
What is the configuration that you are trying to calculate end to end
loss for? The first MIC in any FDDI cable plant -- that is the one
that is plugged directly into the FDDI transceiver -- has essentially
zero loss. This is because the output power of the transceiver is
measured using a MIC connector. So our starting launch power is that
which exists just 'inside' the optical fiber at the MIC connector.
The same is true for the MIC connector at the receiver end. Essentially
all of the light that exits the fiber at the MIC connector gets
captured by the receiver.
If additional MIC connectors are used in the cable plant, then their
losses must be added to the cable attenuation in order to determine
the complete end-to end loss. A typical connector loss would be 0.7
dB. *BUT* this can vary from vendor to vendor and MUST be verified
for each vendor or connector type you use.
A final check would be to measure the end-to-end loss of the installed
cable plant.
Dick Kirk
Network Product Support
| |||||