Question # 1 We currently own an HME DX200 + BP200 used in a theater environment.  We are very happy with the performance in terms of audio quality, build quality and ease of use. However, the one area that causes problems is reception range.  Our site is fairly ?concrete heavy? and we struggle to set up the system with acceptable operating coverage.   We have tried various experiments with remote aerials and aerial placement but ultimately are unable to cover the areas that we need to.
 
Reading the DX210 manual I understand that we can Daisy Chain  multiple DX210 base stations to achieve greater coverage ?
 
So for example if we had two rooms where the Base Station coverage only covered1 room, we can put a primary base station in one room, secondary base station in a second room and link with the 2-wire connection.  Then move between the rooms with the beltpack communicating with the base station it is closest to. 
 
Users in room one and room two would be able to hear each other. Is this correct?  

Answer # 1 Multiple basestations· With the DX range you can have main and up to 3 secondary base stations .. however this does not allow BPs to roam between the base stations it only allows the base stations to frequency co-ordinate together so that they do not clash in the RF space. A beltpack can only be registered to one base station·         

By linking the Party-lines together it allows BPs on the 1^st base station to talk to the other beltpacks on the 2^nd base station , but you cannot roam between base stations.·         

Using a 2^nd base station in the area that you are trying to cover and linking it back to the 1^st base station is a good way to solve your problem ..if your workflow allows for the users on the 1^st base station to remain only within the area of coverage of 1^st base station and the same is true for the users on the 2^nd base station·         

There are other possibilities like using one of our other RF products or possibly using some sort of RF distribution / amplification system :·         

Note:  we do not sell RF distribution / amplification systems but do know of some 3^rd parties that we can put you in contact with

Question # 2 Also, is this functionality possible with a combination of DX210 and BP200packs or do we need to upgrade to the BP210 beltpacks.  
 Can we mix and match BP200 and BP210?

Answer # 2 Mixing BP200 and DX210 base station·         

Yes this is possible. The DX210 is a two channel base station and the BP200 is 1 channel beltpack , so if you registered a BP200 on a DX210 base it will only talk / listen on 1 channel

Question # 3 Can we still link into our Party-line system while the base stations are linked so that party-line users can still hear beltpack users regardless of which roomthey are in?

Answer # 3 When linking two base stations together via Party-line we recommend to put a party-line PSU in the middle between the two units so that it can drive the PL circuit properly and provide termination.