Hello, There are only two other options to connect the wireless headphone transmitter to your receiver (aside from the headphone jack). They would be to either use a speaker level, to line output converter, connected in parallel to the speaker connections (you could use speaker "B" so that you can switch off your mains when listening to the headphones). Or, getting a pair of RCA "Y" splitters, and connecting the headphones in the Tape 2 Loop. You would then switch on "Tape 2" to listen to the headphones through the system.
The speaker to line-level converter can be found here:
The RCA "Y" splitter can be found here. You'd need to use 2 of them. Each one would have it's male ends connect to one channel of the tape 2 "Play"(Input), and "Record" (Output) respectively. The female end would then connect to your headphone transmitter, and you'd simply select "Tape 2 Monitor".
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