AEA failed about a decade ago. Timewave acquired the digital stuff,
TNC's and such, and another company which did business as AEA
Technology or similar, acquired the RF stuff. They used to advertise
antenna analyzers in QST, but I haven't noticed their ads in a while.
If you can't locate AEA Technology, drop a line to tech support at
Timewave, and perhaps they can give you a pointer. Also, try Goggle
at "AEA AT-300" which brings up a lot of hits.

My first TNC was from AEA, and until a recent lightning strike, it was
still working perfectly. Good company, but some bad internal politics
seems to have doomed them.

Alan
WA4SCA