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MC3GX60V - rf gateway needed?

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treybeam
MC3GX60V - rf gateway needed?

Does the MC3GX60V require an rf-gateway and timing server if you are simply doing cable modems? We want to hook it up to the plant just like our 20x20 cards. We have been breaking up our apartment complexes into separate legs in order to put each leg on its own 20x20 to maximize the bandwidth per sub. The use of the MC3GX60V would minimize or eliminate the need to do this. In addition, its more cost effective currently. Thanks.

mbowe
The 3G60 has the upstream RF

The 3G60 has the upstream RF built in (same as you are used to on 20x20)

However the downstream is ethernet out, and thus needs DTI and EdgeQAM

treybeam
Thanks for the quick reply.

Thanks for the quick reply. I just got my hands on one and noticed that it only had US connections. I can also see from a sample config I was sent that the downstreams require an IP and MAC for the associated gateway which is quite convenient. I noticed that they are broken up by 3 sets of 24. Do you know if you can reuse the same frequencies for each set of 24 and send them to separate gateways? I have some larger apartment complexes that have more than one leg of cable and we thought we would consider putting a gateway on each instead of combining it all. We would use separate launch amps of course. One major reason for this is to get more US out of each leg. The cable techs have been using a diplexer that cuts off at 42MHz but I noticed that some configs I have looked at go up to 56. Can we simply use a combiner so that we can utilize US up to 56? Thanks in advance for any advice.

mbowe
Yes you can re-use downstream

Yes you can re-use downstream channels, typically you would send to different RF ports on the same edgeQAM.

You could also send to different edgeQAM instead, but be aware that each edgeQAM needs to be connected to your DTI.

The 3G60 card is capable of 5 to 85 MHz upstream.

US > 42MHz has a few advantages. Less noisy and gives more room to run more upstreams.

BUT

1/ Your plant needs to support it.
You would need to upgrade or eliminate any equipment containing 42MHz diplex. Eg amps, equalisers, headend diplexors etc.

2/ Your modems need to support it.
DOCSIS modems will typically be able to go to 42MHz max. We stopped buying DOCSIS modems a few years back back and started buying dual-mode DOCSIS/EuroDOCSIS modems instead. These dual-mode modems come with a 65MHz or 85MHz internal diplex. You can keep running them in DOCSIS mode (6MHz DS width) but at same time take advantage of US channels > 42MHz. We use attribute-masks in the cm config files to ban DOCSIS modems from using the channels > 42MHz. Dual mode modems are allowed to use any/all channels.

docsis