VOIP Tech Chat → [Vonage] Weird Caller ID problelm with Vtech 2-line phone

My setup is like this:
Cable Modem-Router-Motorola DTA-Vtech 20-2481 2-line cordless phone

I have one line from the telco and the Vonage line and the 2-line 2.4GHz phone. If a connect to the Vtech phone either of the two lines, then the Caller ID functionality is fine. If I connect BOTH of them, then the telco Caller ID is fine but the Vonage one does not give any Caller ID information. Otherwise they both work.

I've heard about Vtech phones having problems with Vonage but this is really weird. Something is interfering between the telco and the Vonage line. I have called both Vtech and Vonage support without any results so far.

I have the Vtech 2-line 2.4GHz phone - just recently got a 4-phone setup to attack phone clutter. Like 8 phones in 4, and they all program in the same way. Sort of my wife's idea, actually. Meant we got to give away a pair of Siemens, stash some old AT&Ts and Vtechs, and throw out a Phonemate. Nice! As for your question, I have POTS on line 1 and Packet8 on line 2. The caller ID number shows up fine when a call comes in to either line.

I've experienced the same on my AT&T 2 line 2462 setup.
(I think VTech makes this for AT&T)

Screwed around with different scenarios to try to get it to work (connect telco line after powering up DTA, etc.) and didn't have any success. I had P8 previously and experienced no problems with caller id.

I didn't find a solution, so I'm not using the two line capabilities of my system and have the Vonage line connected to a 3 Line Venture desk phone where both caller ids work correctly.

I'd be interested to find out why it doesn't work and if Vonage has any suggestions/solutions.

Hmmm I have a related problem with 2 lines as well. My problem is that on my 2 line phone (Meridian 9417) the PSTN or POTS line rings fine, while the VoIP line doesn't ring. (Keep in mind the VoIP line works, there is just no audible ring from the phone when calls come in.)

In testing/checking each phone device connected I started to note the load numbers for each phone device. These load numbers represent how much "weight" a phone device will place on your phone system. I've heard the total for all phone devices on a POTS line should be around 5 or 6, while on a VoIP line it's around 3 or less (depending upon the gateway). The load number is usually printed on the CSA (in Canada) or FCC (in Usa) label on the bottom of the phone.

I found that phones individually with higher load numbers (1.6+) didn't ring with the VoIP line, while phones with lower load numbers ( 1.1) did ring. It would be interesting to see if there is any similar issue here with Caller ID.

I am using the same setup, but with the VTech 20-2438. The phone has incredibly poor quality, and I regret buying it, but the caller ID does work properly with POTS on line one and Vonage on line two.

Before upgrading all my phones, the best phone I had was a two handset, one-line Vtech gigaphone 2431. It was so good, I bought its two-line twin, the Vtech gigaphone 20-2431. It seems equally good. Excellent voice quality. I think it's even better on line 2's Packet8 than on POTS, but very good on either. The phone is also pleasantly lightweight. If I had to go out of my way to find fault, it would be that the second line of the caller ID dispay should have a larger font size. Since I have a total of four two-line phones going through the Vtech 20-2431 base unit, my home wiring has lost much of its relevancy.

Have you verified the polarity of your phone wiring? Most devices now days will work fine if the tip and ring (green/red wires) are reversed. But maybe with a two line device and the two devices wired backward from each other it is causing a problem?

It must not be the polarity.
As I said, if I plug either of the two lines (POTS, Vonage) separately on either of the 2 jacks of the phone then the caller ID for the plugged-in line works fine. It is only when I plug in both of these lines on both of the jacks that the Vonage Caller ID does not work. The POTS Caller ID works fine and other features of the lines seem to work OK too.

No, I understood what you said the first time. I don't think you understand what I am saying so I will explain it some more. Let say on one line you have tip as plus and ring as minus. The other line you have tip as minus and ring as plus. As long as only one line is connected the phone can correct for any reverse polarity. But when both lines are connected you have a mismatch in polarity. If the the two lines are not completely 100% isolated, if there is any circuitry between the two lines, then the reverse polarity could effect both lines.

I am not saying this has to be the answer but it is certainly worth checking.

Kokoss,
I have the same VTech phone system and the Motorolla. I had a similar problem when I first got my Vonage line. It replaced my POTS line, with the second line being an AT&T beta VoIP line. The AT&T line worked fine on its own, but the Vonage wouldn't pick up caller ID if both were connected.

It took about 6 calls to different tech reps at Vonage, before one of them finally found a firmware update that fixed the problem. I suggest calling them to inquire. Back when I had problems, the first 5 reps told me this particular model VTech wasn't compatible with Vonage caller ID, so don't give up easily.

Camelot One,

this is my Motorola version information
(from »192.168.102.1/mainhelp.html):
Software Version: VT20_01.1.12
Bootrom Version: VT20_01.1.12
Hardware Version: Model: VT1000 Revision: 0 BSP: 1.2/0
Config File Version: 4770851

Could you please check yours to see which firmwire release I need?

Software Version: VT20_01.1.12
Bootrom Version: VT20_01.1.12
Hardware Version: Model: VT1000 Revision: 0 BSP: 1.2/0
Config File Version: 5048414

Camelot One,
looks like our Motorola configurations are exactly the same, but I still have the problem. The Vonage technical support said that the config file version is a constantly changing variable that does not effect the device in any way that deal with your phone.

More importantly their Customer Service Rep concluded:
"we officially don't support 2-line phones"

So I should throw away my phone, right?
I thought a primary reason to use Vonage is as a 2nd line (since it is not a reliable primary line for emergencies). So Vonage is actually suggesting we should have 2 different phones to carry around the house....

Well like I said, I went through several reps telling me my model Vtech just wasn't compatible with Vonage, before reaching one who was willing to do some work. We have the same model phone, same motorolla, same VoIP company. So just keep calling until you reach a rep willing to earn his minimum wage.
One thing I learned, its not worth arguing with the same guy. Just call back and get another rep.

said by karlj1:

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Hmmm I have a related problem with 2 lines as well. My problem is that on my 2 line phone (Meridian 9417) the PSTN or POTS line rings fine, while the VoIP line doesn't ring. (Keep in mind the VoIP line works, there is just no audible ring from the phone when calls come in.)

[snip]

I found that phones individually with higher load numbers (1.6+) didn't ring with the VoIP line, while phones with lower load numbers ( 1.1) did ring. It would be interesting to see if there is any similar issue here with Caller ID.

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I have the same Meridian phone. In fact, I have three of them (1.4B REN each), an AT&T 962 2-line (0.0 REN), and a Sony 2-line cordless (0.1 REN) all attached. In addition to these 2-line phones which are connected to both my remaining POTS line (L1) and one of my Vonage lines (L2), I have an old Western Electric 2500 with a LOUD mechanical bell (1.0A REN, by definition) in the basement on L1, and an AT&T clock radio/phone (1.3B REN) in the bedroom on L1.

So my current line 1 (POTS) load is 6.60 REN, and my line 2 (Vonage) load is 4.30 REN. Everything, including caller ID, works fine on all the two line phones on both lines. I am currently in the process of porting my POTS line to Vonage and I suspect I may have to make some changes to lower the load on that line. However, I don't think the ratings are accurate. I believe (and admit I could be wrong) that the REN numbers on the electronic phones represent the REN when they are not powered by AC. The 9417s and the 962 will ring on line 1 (only) in a power failure. The 962 has batteries in it for this (hence REN 0.0) so it isn't drawing ring current, but the 9417s do not and thus get their ring current from the phone line. I doubt that the 9417 really is 1.4 REN when powered by AC.

Note I am using the Motorola VT1005 which has has a capacity of 5 REN @ 2000 ft according to Motorola.

karlj1: Really dumb question here and no offense intended, but is the ringer turned on on the Vonage line on your 9417? You do know that the ring tone and volume is individually settable per line on that phone, right?

Where you able to fix your problem? I am having the same one: Vtech 20-2431 and Vonage with Motorola device, and I can't get Caller ID when both a POTS line and a Vonage line connected to the phone, but Caller ID fine otherwise.

No, unfortunately the problem remains. I have tried reversing the polarity of the circuit as one poster suggested, but it did not work.

Vtech is still "investigating" this problem, almost two months later. I don't know between them and Vonage who is at fault.
I will probably return the phone and try to find one that works.

I was able to fix the problem. But it is a good thing that I am an electrical engineer. The problem seems to stem from improper grounding or parasite voltage on the Motorola ground and from this noise going from one line to the other in the Vtech phone. Neither thing should happen, but I guess they do.

Here is what I did:
1) First make sure that your telephone wires are not crossed. The green wire should be at 0 V. Modular connectors reverse polarity, so be careful. The red one should be at about -48 to -52V when the the lines are not used.
2) I jumped together the 2 green wires. This seems to eliminate the noise and properly ground the Motorola.

I made multiple tries tonight, and it seems to work. I will use it over the next few days to make sure everything is Ok, but so far it is good, except for a slight buzzing on the lines - very faint.

Let me know how if this works for you.

Further to my earlier "experiment", I put a 300 k ohms resistor between the 2 tip wires. This reduce the static noise and still allows caller ID to go through.

I still do not know what cause the problem, and I do not like the idea of having to connect together the 2 phone lines, but it seems to work!

That's some good info bmarcoux. Without the resistor or jumper, what was the voltage difference between the 2 tip wires. Thanks,

Less than 1 V DC, but about 14 V AC with my voltmeter. I was surprised to see such high AC component. I do not have an oscilloscope, so I have no idea what the waveform is like, or what are the harmonics. It might be that a strong AC component from the Motorola gateway is causing problems within the Vtech phone.

I have a three line Nortel Venture Phone. My BVD incoming caller ID was not showing up but my POTS line was. I had VOIP on line 1 and POTS on line 2. After reading this forum, I put POTS on line 1 and VOIP on line 3. With physical distance between incoming RJ-11 wires - problem went away. Go figure.

That might have been enough to increase the isolation between the lines. This issue is very sensitive to its environment.