Obi110 Phone port not working but line port okay

[Peace712]

Hi,

I have an Obi110 set up with Google Voice. After few months of use, the phone port stopped working (no dial tone). Has anyone had this problem? Any suggestion would be appreciated.

The other port (line port) is working fine. I can call the GV number and route the call via line port using automated assistant. So, the device itself is not dead, it's just the line port that has problem.

Thanks
Peace

[azrobert]

Try a factory reset. There is a reset access hole on the bottom of the OBi110. Press and hold the reset button with a paper clip until the unit starts to reboot.

If you only had it for a few months, it still should be under warrantee.

[drgeoff]

Point a browser at the 110's IP address on your LAN and log in.  admin and admin are the defaults.

On the left hand side click on Status,  then Phone and Line Status. With the phone on hook what do you see for VBAT and TipRingVoltage on the Phone port?

[restamp]

OK, now that you've mentioned them, can you explain what "VBAT   56 V (11.8 V)" means?

Inquiring minds want to know.

[carlyle705]

me too.

[drgeoff]

I don't know what they mean. 

My guess is that circa 50v figure VBAT is the voltage which the OBi generates to substitute for the Exchange (Local office in US parlance) battery.  The circa 12 volt figure in brackets may have something to do with voltage feeding the dc-dc converter which generates the circa 50v.

What I do know is that if those figures are way off those numbers, then the PHONE port does not work. 

[SteveInWA]

I don't know what they mean. 

My guess is that circa 50v figure VBAT is the voltage which the OBi generates to substitute for the Exchange (Local office in US parlance) battery.  The circa 12 volt figure in brackets may have something to do with voltage feeding the dc-dc converter which generates the circa 50v.

What I do know is that if those figures are way off those numbers, then the PHONE port does not work. 

Historical explanation:  traditional telephone systems (central office connected by copper wire to the telephone in your house) ran on rooms full of batteries, with the typical voltage being 48 volts DC.  When the phone was "on-hook" (not being used), measuring the VBAT (battery voltage) across the pair of wires would show ~48 volts.  When the handset was picked up, an approximately 600 ohm impedance across the wire pair would lower the voltage to around 12VDC.  When the phone was on-hook and ringing, the voltage would go up to nearly 100V AC to make the coil-operated bell ring.

Modern ATAs like the OBi have an internal circuit (known as the Subscriber Line Interface Card or SLIC) that up-converts the ~12VDC power from the power supply into the standard telephone voltages to operate the attached telephone set.  Sometimes, that SLIC fails due to stress (power surge, improper connection, etc.), and thus, looking at that value is a good way to tell if your OBi is now defective because the telephone line interface has gone dead.

[Peace712]

Thank you all.

It's still under warranty but the problem is it's not here in US. I can still access from here. So, I will try factory reset and report back if I get anything.

[restamp]

Thanks for the information, SteveInWA and drgeoff.  So what's the difference between VBAT and TipRingVoltage?  Offhook or Onhook, it seems VBAT is always about 20% greater than TRV.  Any ideas?

[SteveInWA]

VBAT is the SLIC setting.  TipRingVoltage is the actual voltage measured across the two wires going to the telephone jack.  I wouldn't worry about why they're different.  As long as the value is roughly around 48V, it's working.

"Tip" and "Ring" refer to the ancient telephone plug connectors as seen on old photos of telephone operator consoles.  The tip is the electrical contact at the end of the plug, and the ring is the electrical contact below it.

[Peace712]

Point a browser at the 110's IP address on your LAN and log in.  admin and admin are the defaults.

On the left hand side click on Status,  then Phone and Line Status. With the phone on hook what do you see for VBAT and TipRingVoltage on the Phone port?

Finally managed to get the device. VBAT and TipRingVoltage are listed as 0 V (11.8V) and 0 V. What does that meant? Is the phone port dead? As I said line port works fine and I can call OBi and route calls to line port using AA.

[drgeoff]

That certainly does not look right.  But I'm puzzled by two things.  I can envisage the voltage step-up generator failing and giving no or low volts on the PHONE jack but the LINE port is also showing 0 volts.  The LINE port volts comes from the telco line.  And you say the LINE port is working OK.  Or have you done the test with the telco line unplugged?

Screenshot from my 110.

[Peace712]

I am sorry for late reply. I didn't get notification of the post.

Yes you are right the snapshot was taken while line port was not connected. Is there any thing I can do to make it work? Or is it now just a brick?

[SteveInWA]

Time for a new one.

https://youtu.be/MH7KYmGnj40