sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems 551 KSU On hold music or Click Click?

Aloha from Hawaii and thank you in advance for this great fourm and help. I tried searching and didnt see what i was looking for. How easy is it for me to add music on hold or get the great "Click Click" on hold? Mahalo, David

I'm not sure what the great "Click, Click" is, but Music on Hold is do-able on a 551. You will need the right line card - and ITT 400E or a SanBar 4200 or a WE 400H. There are some others that will work - a 400D will NOT. (Strapping on the card may be required, depending on the model.)

To supply MOH to more then one line you will need a 403 card to isolate each of the lines and prevent crosstalk. If you just want to supply it to one line then, as I recall, you remove the wiring on pins 3 & 18 (A Battery & Ground) and attach a low level Music source to those pins.

I think that was it, but I'll go dig up some prints and check. In the mean time I'm sure that someone with a better memory than I (Ed or Arthur or....) will come along and correct me.


Sam

Mahalo for the fast response! Im looking forward to trying the music. One line is good for now. I do have WE 400H cards. The great click click is the sound you hear when you are on hold. Almost like a winking but the on hold party can hear it. I wasnt sure if the 551 was capable of it or was it just something for old very large key systems. Looking forward to music soon with your direction. Aloha from Hawaii! David

The "click-click" that you speak of was an indirect result of many stations and very long cable runs sharing the same line appearance(s). The hold wink of lines managed to create enough of a capacitive kick to be picked up by the caller on hold. I don't think that this was ever intentional. You might be able to recreate this effect by completely isolating your system's power supply voltages from commercial ground. This is usually done by disconnecting a metal strap on the lower-right corner of the 551's power supply front panel. This strap bonds the low-voltage outputs to the commercial AC power ground. Of course, you will need to remove any other external grounding to the KSU as well so that the power supply outputs are truly floating. Don't alter the AC power cord's grounding conductor though. If you don't get the click by doing this, you might have better luck using ITT 400E line cards and running a strap from the "LW" terminal on the lower-right quadrant of the KSU's 66 block to pin 18 of the line card's slot. If you have a 551B KSU, the leads that are wire-wrapped to pins 3 and 18 of card slots 1-3 are not terminated, but they are taped and stored near where the wiring harness from the card cage enters the right side of the block. They are white/blue through white/green pairs according to the slot position.

Mahalo Ed, will work on that. Still have some daylight here in the islands!

How about that. All these years I thought that click-click the caller hears while on hold was to assure them they had not been disconnected. I recall hearing the click-click-hold "feature" on solid 1980s Southern Bell installations. Learning new stuff in fun.