It is the cybernet type board clone for the 148 GTL DX ?
Like this : http://www.cobraworxshopz.com/cobra_148_clone_43.html ?
Pretty sure that's the AM modulator transistors. Yeah, it 'regulates' the AM carrier as well. It's a NPN transistor, and there are a lot of them that will do the job.
We have used 2SD613, MJE3055T, TIP41A, B or C. Don't know the number used in that generation of 148GTL radio. There are literally dozens of generic NPN power transistors that will work.
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