Another MOH question

[LeMarsInsCo]

Hi all,

I'm not any type of Nortel tech person or anything like that but I was given the responsibility to maintain basic stuff such as extensions and voice mail.

We have a Nortel Meridian 1 PBX... Back several years ago our building's analog music feed was also fed into our PBX for MOH... the device that converted the music from analog to digital quit working for whatever reason and management at that time said we didn't need MOH... as you might guess management has now decided we should have MOH again... the converter/transformer device was removed back then and no one seems to know where it went so I have no idea of any type of make or model number or anything. I seem to remember it said AT&T on it but not certain about that.

Anyhow, anyone have any idea of what type of converter or transformer device we might have been using to transform the analog music signal into the digital signal the Meridian PBX would understand? Also, any ideas on where I might pick up such a device?

Thanks for any help… sorry this got so long.

Tim

 

[acewarlock]

More than likly it was an impedence matching transformer and not a converter connected to a trunk card.




This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[LeMarsInsCo]

It appears the wires that ran from the old device to the PBX hooked in at the same area as a couple of RAN boxes we have... does that help at all?

 

[acewarlock]

Where do the wires go on both ends????? That might help




This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[johnpoole]

what are you going to use for a source for moh? either way, the output of that is going to be between 8 and 2 ohms.. the trunk card is 600 ohm.. go to radio and get an 8 ohm to 600 ohm impedence matching transformer.. then prt mus in ld 20.. connect to that tn...

john poole
bellsouth business
columbia,sc

 

[LeMarsInsCo]

The source of the music is just a two wire analog feed from our building's music system. I took an old PC speaker just to verify it is analog and still working... I hear music!!

Is this impedance matching transformer something I will have to build or is there something pre-built I can get?

ld 20, prt mus shows the following...

TN 012 0 00 07 (Next to RAN boxes mentioned above.)
TYPE MUS
CUST 0
XTRK XUT
TIMP 600
BIMP 600
RTMB 20 1
CFLP 30
DATE NO DATE

Do I care about any of the other settings?

Thanks again for your assistance.

 

[LeMarsInsCo]

And just to make sure I'm understanding this correctly...

The 8 omhs is input and the building's music connects here... the 600 omhs is output and connects to the phone system.

Sound right?

 

[acewarlock]

You can buy them, radioshack may have them.

No you don't care about the settings, but stat the cards.

"The 8 omhs is input and the building's music connects here... the 600 omhs is output and connects to the phone system." Correct!




This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[acewarlock]

This may have been some kind of Ampiflier so the Volume could be adjusted.




This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[acewarlock]

Found this on google

http://www.pasosound.com/PDF/BGM/OM167.pdf

This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[mjpearson]

A couple of things to keep in mind relative to using the xformer.

1) The xformer may need some grounding (tie one of the leads to ground).

2) Without the xformer, you may experience 60 hz noise but the xformer may remove a lot of it.

3) If you're using a radio for MOH......there are some FCC rules that will apply. Technically you need permission from the radio station to use their signal for MOH.

 

[LeMarsInsCo]

This is a subscription music service our building has... Muzak I think.

I'm having very little luck finding a transformer with 8 ohm input and 600 ohm output... I'm finding lots of stuff that goes 600 ohm input and 8 ohm output but that doesn't do me any good.

acewarlock, that amp you found looks like it might work but it sure has a lot more bells and whistles than what I was looking for.

Anyone know of a good supplier/vendor that would have a self contained 8 ohm input/600 ohm output Impedance Matching Transformer?

 

[acewarlock]

I think the 8 ohm input and 600 ohm output will work in reverse. normally it is used to go from the trunk card to a page Amp. You only need a cheap Amp to control the Volume. Just search the internet an you will find something. If you don't get an Amp the Volume will be very low and you may not be able to hear it.




This is an Analogy so don't take it personally as some have.

Why change the engine if all you need is to change the spark plugs.

 

[LeMarsInsCo]

OK, now I'm totally confused... which really isn't too hard to do.

In the process of searching for a Impedance Matching Transformer I was seeing a lot of amps that do this... our building's music already runs through an amp so I thought perhaps there just might be a 600 ohm output already on the amp... and I was also curious as to what the wires that use to feed the MOH were hooked to. What I found suprised me.

Besides wires feeding to our building's ceiling speakers there was a single phono type connector running up to a circuit board... the board is an Atlas Soundolier model LT600-VC...

http://www.atlassound.com/support/SLSheets/SL8.1434.PDF

The wires that run to our phone room are connected to the 600 ohm output on the left side of this board... since this is 600 ohms I should be able to connect it directly to the MOH TN on the phone system, correct?

I have no idea what the device was that the MOH use to feed throught before... maybe a filter of some kind. Hmmm.