search for: 75ohm

Hello Im from Denmark and i've just got my Digium TE405P. But i have some problems when i connect it to my E1 connection (ISDN30). My telco delivered a alcatel box witch have a G.703 120ohm (DB9 with a serial to rj45) and a 75ohm coax connection. I've tried to connect using the 120ohm with rj45 and a ordinary utp cable. But it dosent seem to work. I've tried several zaptel.conf setting, but none of them made the led stop blinking. <my current zaptel.conf> span=1,1,0,ccs,hdb3,crc4 bchan=1-15 dchan=16 bchan=17-...

...ontext=pri1 channel => 1-15,17-31 I am connecting my TE110P with a Balun converter where the two BNC connectors are from connected to a Fibre optic line. When I reboot my pc , I got my TE110P LED flashing RED slowly. But nothing happen when I hooked up to Balun Convertor. Balun convertor is 75ohm on BNC and 120ohm on RJ45. I am using straight through cable to connect my TE110P to Balun. Anyone please help? Regards, Stephen

Hi, Digium's E400P has RJ45 conector and my E1 link has BNC concetor. Could someone tell me the cable pinouts to make this conection? thanks Eduardo

Hi ! I am trying to configure two E100P cards, but I am a bit confused with zapta.conf in what I am trying to achieve. The * will be connected to a pstn switch with two E1 PRI lines. The E1 lines will be used for incoming calls as well as outgoing calls. My problem now is what to put in zapta.conf, I would like to group all channels from both cards together (if that's possible). Does this

...>The problem with using CAT5 for long telco runs is that the impedance is >wrong at the line clock rate (~1MHz). IIRC the impedance for telco is >specified at 600 ohms @ 1MHz, whereas for CAT5 the impedance is actually > T1s are always 100-110ohm, E1s are the same when on pairs, and 75ohm on coax. Only analogue pairs are terminated at 600ohm, and no line can actually be greater than 120*PI (about 377) ohms - that is the impedance of free space. Fudgy 600ohm stuff works at audio frequencies, but you have to treat the line properly as a transmission line as the frequency rises....