3 ms·
Err in this case, the modems would both need to connect to "FXO" ports. All they actually need is loop current. The simplest circuit is just a battery, resistor
by gorkish 3y ago
Err in this case, the modems would both need to connect to "FXO" ports. All they actually need is loop current. The simplest circuit is just a battery, resistor, and capacitor. Fun tip: this also works to directly connect DSL modems.
- Scoundreller 3y agoI thought that only worked for SDSL modems?
- gorkish 3y agoYes it requires that the DSL mode is compatible. Also on second thought I am 99% sure you don't need a wet loop for naked dsl, but you certainly do for analog modems. Sorry for the misleading info; it has been /a while/ since I hacked on copper PSTN stuff...
- kjs3 3y agoYou're right; don't need a wet loop for DSL. We used to back-to-back DSL modems without them all the time. At least for particular brands (which often advertised they could do this)...maybe there were some that didn't support this. I had a guy on the team in those long ago days who figured out how to channel-bond a pile of SHDSL modems over a couple of intra-campus phone cables (much less than CAT3 conformant) to get almost 10base-T speeds over a couple of 100m. In the end, we decided the cost of running a fiber was going to be less than the cost of maintaining the DSL solution, as clever as it was, and gave the upgrade path to whatever we wanted.