Hi Mike,
We have a number of similar users here, and have used the Walker amplifier (W-10) quite successfully. With this amplifier connected you don't need a separate handset just use the standard Cisco handset that was shipped with the phone.
Here's an "old" clip from the 7940 data sheet that highlights this product. This is how
we first stumbled upon it
The handset is Hearing Aid Compatible (HAC) and meets FCC loudness requirements for Americans with Disabilities Act (ADA). Section 508 loudness requirements can be achieved using industry standard inline handset amplifiers such as Walker Equipment W-10 or CE-100 amplifiers.
From this 7940 doc;
http://www.cisco.com/en/US/products/hw/phones/ps379/products_data_sheet09186a008008884a.html
This is also a very cost effective solution. Have a look (just some examples)
http://www.cdw.com/shop/products/default.aspx?EDC=485315
http://www.handset.com/products/listing/item8.aspx
http://www.harriscomm.com/catalog/product_info.php?cPath=47_167&products_id=804&hcCsid=2c1a1b7103f233e7f2c8c4e145c2da7b
Cheers!
Rob
"I don't know how, I don't know when
But you and I will meet again "
- Tom Petty
