[McMurdo]

we have the Panasonic SDBS 308 at work and it rings 300 series phones no problem, though the one I've tried has been converted to BT plug with a 3.3k bell resistor. I think Panasonic only recommend a ren of 1 on an 'SLT' equipped extension, though I don't know the 206 intimately. (hybrid pabxs from panasonic require a master socket on SLT extensions and a secondary socket for digital keyphones).

An unconverted 200/300 will have a REN of 4 afaik and may refuse to work or even ring trip the PABX.

Our 308 won't accept pulse dialling on an extension (since it uses TBR and will interpret a '1' as a recall) but will convert MF to pulse for the exchange if so programmed.