HI,
I buried the following enquiry in another thread so thought it best to bring it to light in its own thread...
Operating my FT-980 on AM for the first time this weekend, on-air comments suggested that the rig has a modulation issue. With Mic Gain at max, people commented on poor modulation. I can’t get any action at all on the ALC meter in AM and need to almost shout to get it moving on SSB.??
My first thought was the 0.33uF capacitor but, checking the circuit, this is switched in and out using the Tone Switch. Switching from "1" to "2" made no difference.
Could it be the microphone cartridge? How would I test it? Online searching for information revealed very little, it seems this particular microphone (MH-1B8) was not widely used.?
Any clues on testing the microphone, sourcing a replacement cartridge or other avenues of enquiry would be appreciated.
includes photos and a circuit for the microphone.?
If it’s significant, the unit was built in 1985.?
?
All the best,
?
Mark
VK2MOH
