atcomsystems.ca/forum Forums TDM Business Telephone Systems Vodavi Telephones & Systems MOH Input Source

I've been setting up MOH on an XTSc but I'm not sure what type of device to use for the input source. I know POTS lines are 600 ohm, but I don't know if I need to match that...

I connected the headphone output of a PC to the MOH1 port and I could hear it faintly while on hold. I'm guessing I need an amp also, but what wattage, etc.. We are looking for something simple...any device that will play a CD.

Thanks.

The headphone output should be fine by itself. Make sure that you are not using a mono cable on a stereo headset output.

What happens when you put your buttset, in monitor, on the wires your punching to the 66-block? Do you hear music loud and clear?

This reply is not meant to be an insult. I have no idea how much you have dealt with this, so forgive me if I am getting too basic.

A common mistake we see is people plugging a 1/8" phone (headphone) plug into an RCA jack. Many MOH devices have RCA jacks for the 600 Ohm output. RCA (phono)plugs/jacks utilize a 1/8" center pin and a larger outer barrel as the shield. The overall diameter of the jack barrel is about 5/16". A typical phone (headphone) jack is much smaller, not much larger than the 1/8" plug itself.

If my description is difficult to visualize, compare a standard headphone plug to a "red-white-yellow" cable set plug that usually comes with a VCR or DVD player. The VCR/DVD cables use RCA plugs and jacks. It's possible that you are plugging a 1/8" phono plug into an RCA jack.

What happens is that when a mismatched phone plug is inserted into an RCA phono jack, the audio source is connected to both conductors of the phone plug with no ground (return) path. When it doesn't work, people turn up the player's volume WAY up and eventually, the sound bleeds through enough to be heard faintly in the phone system.

It sounds like this may be your problem because all Vodavi MOH inputs work fine with traditional 1/8" headphone jack connections. Again, I don't mean to be trying to teach "plugs 101" here, but I have even seen seasoned professionals make this mistake.

Hope this helps. Oh, and by the way, if I am correct in my assumption, PLEASE turn the player's volume down before you correct the connection. If the volume is too high, you'll blow the MOH input transformer in the XTSc.

I'm not using an RCA, but a TRS (3.5mm) headphone output of a PC. Do I need a specific MOH device for 600 ohm output?

Usually, PC's have two outputs; one that is capable of driving headphones directly and the other is a line-level output that is intended to be the input to an amplifier or amplified speakers. This output's level is constant so as to not overdrive the amplifier's input. No matter how high you increase the volume on the computer, it won't have any affect on the line-level output jack.

I have looked around here an all sound cards I have found have a mike, a headphone and a line-level jack. Does your PC have another output jack beside the one you are using?

If it doesn't, then you will need some kind of amplifier (nothing fancy) that will take the line-level output and bring it up to a volume that is usable. A cheap pair of computer speakers with a headphone jack will probably do the trick. I am sure that Radio Shack or Wal*Mart has something that will suffice. Most speakers with a headphone jack will disconnect the internal speakers when you have a plug inserted. If not, get out the duct tape or go inside and disconnect the speakers.

I still question the ouput you are using from the PC. We have done what you are doing dozens of times from headphone jacks on the PC straight to the KSU with no problem at all. I will be happy to continue to help, though.

I'm using the headphone jack. I think the issue is in my cable, but before I continue I wanted to know what type of input the XTSc is expecting for MOH.

Most MOH devices seem to offer both 8ohm and 600ohm outputs. Which one would I use for the Vodavi and is it Ok to use the headphone output of a CD player or computer as a source for MOH?

the XTS is 600 ohm and for a cheap solution buy walkman and use the line out of it and splice a piece of crossconnect to you 1/8 jack coming out of the walkman so the braided wire does not touch other pins on the 66 block.

I have a similar question. We have a Vodavi Triad S - DVX with feature pack 3.1. I spliced a RCA Headphone extender cable, plugged the headphone end into the source (CD player) and splced the other end twisting red and white cables together and twisted the shielding cable (ground). I connected the red and white twist to one crossconnect cable and the shielding to another crossconnect cable. I punched down the cross connect pair on the green/violet pair on the 1st 66 block. I also tried punching it down on the green/violet pair on the 2nd 66 block. No luck, not hearing any music. What am I doing wrong? Can I just punch down to the pair like this? Is my RCA cable configured correctly? Do I need additional hardware to make this work. The Telephone tech guy said just punch it down polarity does not matter. Any help would be appreciated.

Briandye:

You are punching down to the wrong pair; it is the violet-blue pair. Violet-green is a pair of relay contacts, so that will never work.

The rest of what you are doing with regard to the red & white together for one wire and the shield as the other are fine. Yes, polarity does not matter.

Syme:

Are you connecting your music input to the black/slate pair? That's where it's supposed to be. It's possible that you are feeding into the wrong pair and music is simply bleeding through via paging outputs.