The delay is introduced in the adaptor by the 470Ω variable resistor and 100nF capacitor in the path of the logic signal.
Game software compensates for this delay, and if we don't replicate that in our wired adaptor the aim is off by a considerable margin! One unusual aspect of the Sega Menacer is the delay incurred by the overhead of its wireless communications. The transistor is not fussy, either, and a general-purpose NPN such as the BC548 should do the job well. The diode is less critical and the common 1N4001 works well. When developing the circuit I found that it didn't always function reliably when using the CMOS logic chips I had to hand, but it worked well with TTL logic.Īs such I would recommend using SN74ALS02AN logic chips as I can confirm that they work. Two NOR gates are used to latch the pulse received from the Light Phaser and an RC circuit is used to delay this latched pulse to mimic the delay incurred by the wireless overhead in the real Sega Menacer hardware. The adaptor uses two NOR gate chips for all of its logic.
In the meantime, please check the journal for project updates.
This page will be updated with the improved designs when I have got to the bottom of these issues. If you choose to build the adaptor yourself then please be warned you may be disappointed! I have encountered some compatibility issues with the current Justifier adaptor design on certain models of Mega Drive and all of the American Laser Games titles. To ensure I don't sell anyone a poor-quality product I am also thoroughly testing them with Mega-CD games.
June 2022 update: I have been working on improving these adaptors with the intention of being able to sell some ready-made ones, starting with the Justifier adaptor.