Ap pen dix E - Trou ble shooting
Please check the fol low ing points if prob lems are ex pe ri enced set ting up a BBM link.
1. En sure the Power LED is ON.
2. En sure the mo dem is be ing used on un con di tioned cop per twisted pair wire.
3. Check one mo dem is set to Mas ter, one is set to Slave
4. Check line rate is set the same on both Mas ter and Slave if work ing independently.
5. Check cor rect pin con nec tions on tele phone line con nec tor.
6. If the link will not set up at the higher rate, use 64K rate set ting to check whether the line loss is within
range. If the link works at 64K rate , but not at the higher rates, then the line noise or im ped a nce is too large
for the higher line Rate and a lower Data Rate will have to be chosen.
7. Check that no test loops are ac tive in the mo dem or be ing set by the DTE.
8. Check the in ter face ca ble pin out re quire ments as de scribed in the DTE man u als and Ap pe n dix A for the
BBM. A spe cial ca ble may need to be made for ex ter nal tim ing ap pli ca tions, as per Ap pen dix E.
A sam ple set up pro ce dure fol lows for a pair of BBMs.
Using the front panel push but tons and LCD dis play, set one unit as fol lows.
In the Con fig u ra tion Menu (* Config Menu *) set :
C> Mode : * Mas ter * then press SE LECT
C> Pairs : 1 then press SE LECT
C> Rate : 64K then press SE LECT
C> Clk : In ter nal Clk
Then Press PROG key
In the sec ond BBM, us ing the * config menu * set as fol lows ;
C> Mode : Slave then press SE LECT then press Prog
C> Pairs : 1 [Au to matically set by Mas ter]
C> Rate : 64K [Au to matically set by Mas ter]
C> Clk : Line Clk [Au to matically set by Mas ter]
Con necting the two units back to back should now cre ate a link and the units should be in sync.
Note : If back to back, the power may need set ting to 7.5dBm (see section10.2.6).
If fur ther prob lems are en coun tered, please con tact your lo cal dis trib u tor ini tially or a sk for ascom
Tele com mu ni ca tions Trans mis sion di vi sion Tech ni cal Sup port on - + 44 1222 500 700.
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a telecom User Guide High Speed Mo dems
