Matt,
A ham friend of mine operated his QDX without any antenna connected by mistake.
I repaired my friend’s QDX which had damaged BS170s and IC5 74ACT08. After replacing those QDX worked flawlessly.?
As a precaution I added two 1N4756 47 V/1W zener diodes as shown in QMX manual. He is very happy with it. After this repair session he confessed that he operated QDX without antenna connected once more by mistake and BS170s and QDX are still alive he said!:)
May be you should try this too.
This is the screenshot I used from QMX manual:
Barb WB2CBA