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New Member

Smart serial and Loop-E 2 Mbps converter


We have been facing a strange issue with Smart Serial cards and a Loop-E converter. there is a 2 Mbps link and the link does not come with a smart serial card but the same comes up perfectly fine with a NM-4T card. the strange part is we have a different Loop-E converter and the it has been working perfectly fine on a 1700 series router.

Note:- The current link has been tested on a cisco 3745 and a 2651XM router and it does not come up and the same link comes up with a NM-4T card on a 3745 router.

Has anyone faced such issues in the past??


Re: Smart serial and Loop-E 2 Mbps converter


I did face similar kinda problems earlier wherein we ended up in patching the line coming from the Telco on different pins.

Would suggest to try to change those connections if possible and check.

Also during offpeak hours u can try this converter with the other link and check.

Also check out the settings on the converter related to framing as well as the timeslots configuration if u running with framed mode setup..


New Member

Re: Smart serial and Loop-E 2 Mbps converter

hi prem,

By different pins, do you mean the connection coming on the krone block???

moreover we have tried the same converter on 3 different routers having smart serial cards.

The same converter works perfectly fine on a NM-4t card.


Re: Smart serial and Loop-E 2 Mbps converter

Hi Sai

I too was mentioning the krone block only from where u r extending the physical link to ur router interface.

Also have u checked up with the modem vendor regarding the same ??


New Member

Re: Smart serial and Loop-E 2 Mbps converter

Hi Prem,

We have already tried using diff pins on the krone block and moreover the service provider has little idea abt this issue.

we replaced the loop modem with a RAD FCD and everything is fine.



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