Wireless Mic Question

[CBR372]

So I got a phone call the other day from a local art museum that they needed some help with their wireless mic system. Currently they have one Shure Brothers T4V Diversity Receiver - Vocal with a SM58 (T2 Wireless transmitter) wireless handheld. It's operating at 169.445 MHz. They originally wanted to add a headset style microphone (I call them Britney spears microphones)to their original system. In my research though it would appear that finding something in that same frequency may not exist. Meaning I would have to spec them a new system (base and 2 mics, handheld and headset) however I am worried about one part of this. there is a concrete wall that is about 9" thick that separates the booth where the receiver sits to where they would be using this mic. and the room they are using the mic in is fairly large. they tell me they have no problems with the current system in terms of the signal cutting out.

I looked at new shure systems and I found that most mics had a transmit power around 30(can't remember the units) but this current SM58 transmitter is at 50.

I am worried that new systems might not be powerful enough/ the transmit frequency is now much higher (now in the 400-500MHz range instead of 169.445Mhz) than this system and may not go through that wall.

Thoughts, ideas, recommendations? I don't want to recommend a system that is not going to work in their space.

 

[FMEng]

The difference in power level is very small, <3 dB, making that irrelevant. While the concrete attenuates more with increasing frequency, the rebar has more effect as frequencies drop. The higher frequencies are smaller wavelengths, so they fit through the gaps in rebar more easily. Years ago, when radio paging went from VHF to UHF, building penetration improved greatly.

My guess is that the UHF system will work fine. If it doesn't, drill a hole in the wall and mount the antennas on the other side.