Ooma Forums

I've seen that Ooma supports older analog phones, so I pulled out an older phone from the 90s, and it does work to receive calls, it rings, can answer and hear, etc., but it does not dial out at all, it's just a constant dial tone, pushing the buttons does nothing.

I've even tried the phone at another place that had a different service and same results, dial tone, receive calls, but not able to dial out. It's set to tone I've double-checked to make sure.

Has anyone else run into that issue with older phones? I'm at a loss now, It's possible it's the phone, but it seems to work fine short of not being able to dial, you can push any number button, but the dial tone keeps going, there's no tones from number keys.

It might be your phone. I have an old phone hooked up and it works just fine.

I thought maybe it was the phone at first as well, but seems the Ooma possibly doesn't output enough line voltage, so I decided to put batteries in since it's an old one that has battery backup for when the power is out to store caller ID and a clock, and now it seems to dial.

So now I'm wondering if Ooma only puts out either 12 or 24V and if there's something out there that can boost that up a bit to work properly. Or at least that's the theory I'm operating on now, I'd never tried the batteries for the backup because it should work off line voltage (well in a traditional sense anyways) so that was an interesting discovery, I'm assuming some kind of booster or something might be out there?

Older touch tone phones did not have a polarity guard so the red and green wires had to be connected properly for the tone part to work, yet everything else will work.

Try reversing your red and green wires and see if that fixes the problem. I believe it will.

If you have the modular plug from the phone going into a wall jack, you could reverse them there, or you may have to open up the phone and reverse the red and green spade lugs where they attach on the big block.

Let us know if this fixes it and good luck.
RT

Thanks much for the suggestion. I'm more certain the phone is either late 80s or early 90s now, it's a Sears SR3000 series (model 34761 40 memory with an LCD display to show time and number dialed, no CID).

I decided to open it up and look inside, and it's just a two wire, red is ring and green is tip, and of course it has the positive and negative lines coming from the battery to the board. I did notice that even the Mute button on the phone won't work without the batteries either, so that was an interesting find when I opened it up.

Since it's connected straight to the Ooma I decided to make a new wire, I made one end the standard pinout, then the other end I reversed the wires, and it still just had the dial tone, can get calls and sounds just fine, but no buttons worked, outside of the Hold button (which is the only button that works without the batteries) which I find odd that button works but nothing else does.

And I've tested the on hook and off hook voltage, it's 48VDC on and 5.5VDC off, then I added a talk battery boost onto the line, and then retested and was getting 53VDC on hook and 6.6V off hook, and boosted the loop current to be better, so in terms of line voltage, I can't see there being a line current issue now with that added.

I know the manual says the batteries were for backup for when the line power was out... but is it possible that it just needs them for the buttons to work in general? I couldn't really reverse the wires in the phone, as they are all soldered connections.

So, the line into the phone, is a 2 conductor, and the handset is the typical 4 conductor. I thought maybe just reversing the red/green on the other end of the wire would accomplish the same thing, which was why I made a new wire with the standard pinout to the Ooma and then reversed the connector going into the phone and same results, phone gets dial tone, and can get calls, rings and sounds fine talking, but can't dial and no LCD display without the batteries.

If the phone also didn't work at a different place with a different service, then that suggests a problem with the phone. If reversing the wires in the phone cord didn't help, then reversing them anywhere else probably won't help either. It is possible that the phone just needs batteries to work.