Question:

We have a big event coming up in a venue that also uses DECT cordless phones.  The venue management team want to know if FreeSpeak will disturb their telephone system?

Is there a procedure they can do to make sure or prove that our FSII system is not disturbing the phone system?

Solution:

Yes we have a means of interacting with another DECT system, that is what the DECT sync port is for on the rear of the unit / card.

See this FAQ for the DECT Sync IN / OUT pinout details DECT Sync pinout and signal details

In DECT there is a limit on how many radio slots are available in anyone airspace (100 – 500m). The coverage area will vary depending on venue, outdoors have larger coverage area than indoors.

In Europe you can only get up to a theoretical maximum of 50  (FSII E1) or 100 (FSII IPT) in any one RF zone, and if you have 2 DECT systems that are not Synched you can loose 10-20% or more device connections due to DECT systems not being aligned.

First thing is to find out how many DECT phones they have and what the coverage area for the phones looks like.

Second you need to know the brand of phone system and see if it has a DECT sync port.

Using FSII Eque as an an example: Then assuming 20% loss, leaves about 80 available slots in one coverage area and we have 30 beltpacks (which take up 2 slots = 60) which are on and have an RF slot, that only leaves room for 20 DECT phones.  Since we are always on and the DECT phones only take a single 1x slot when making a call I could see how we could cause some DECT phones to not get a RF connection (system busy) if they have more than 20 phones operating in the same area as the FSII beltpacks.

We should be able to overcome this problem with DECT RF coordination once we get the information about their phone system and its coverage area within the venue.