CMTS & CM

Product : CATV
Part Involved : CMTS BSR 64000
Summary: Connections involved from the HUB to the client
Scenario : Troubleshooting and following the best levels of RF
Company : ISP on Ecuador
Reference Date : August 2008.

Recomendations to follow :

- Always check the logic card configuration (domain) if this one was configured like 1x8 or 2x 1x4 and based on this will plug the test cable US / DS. For example ; talking about the configuration 2x 4x1 (with this ISP) DS0 is related to US 0,1,2,3 and DS1 is related to US 4,5,6,7, that is the downstream is loaded by 4 upstream.

- If CM was registered and this one is moved to several hubs, first connect the RF cable to CM and after that turn on it, otherwise the registration process takes more time because it is not going to find the downstream carrier will start to scan frecuencies.If CM does not get up, then check its status like as SNR levels, its probably the attenuation should be adjusted, and cables on bad states can cause communications problems between CM and CMTS

Take next as level of reference :
CMTS Tx = +55dBmV
CMTS Rx = +14dBmV (+/- 1dB)
CM Tx = 35 to 55 dBmV
CM Rx = 0 dBmV (+/- 5 dBmV)