Thu Feb 16, 2023 11:54 am
#1953423
Hi all,
I have a Yaesu FTA 550 handheld in my microlight. As a temporary bodge before I install a proper intercom, I'm using the supplied SCU-15 adaptor. As far as I can tell, everything is in good condition, but though I can head incoming transmissions, the microphone from the headset doesn't work (if I set the radio to 'internal mic', and then speak into the internal mic while wearing the head set, everything seems to be fine).
I've tried it now with three headsets - a DC 13.4, a Peltor 7006 and a Peltor 7004. All seem to be the same. Yaesu's spec sheet for the SCU-15 says:
"Headset specification requirements for the SCU-15
Earphone (Speaker) Impedance: 8 ohms or above
Microphone impedance: 150 ohms +/- 20%
PTT pressed: Ground
PTT not pressed: Open
If a high impedance microphone is used, then a suitable power supply for the electret microphone element and a low
output impedance buffer amplifier will be required."
Though I can't find details for the Peltors, the 13.4s definitely don't have this impedance on the mic - they're 50 ohm. Is this likely to be what my problem is (and why most portable intercom boxes for this application have a 9v battery inside them)? Sorry - well outside my comfort or knowledge zone here..!
I have a Yaesu FTA 550 handheld in my microlight. As a temporary bodge before I install a proper intercom, I'm using the supplied SCU-15 adaptor. As far as I can tell, everything is in good condition, but though I can head incoming transmissions, the microphone from the headset doesn't work (if I set the radio to 'internal mic', and then speak into the internal mic while wearing the head set, everything seems to be fine).
I've tried it now with three headsets - a DC 13.4, a Peltor 7006 and a Peltor 7004. All seem to be the same. Yaesu's spec sheet for the SCU-15 says:
"Headset specification requirements for the SCU-15
Earphone (Speaker) Impedance: 8 ohms or above
Microphone impedance: 150 ohms +/- 20%
PTT pressed: Ground
PTT not pressed: Open
If a high impedance microphone is used, then a suitable power supply for the electret microphone element and a low
output impedance buffer amplifier will be required."
Though I can't find details for the Peltors, the 13.4s definitely don't have this impedance on the mic - they're 50 ohm. Is this likely to be what my problem is (and why most portable intercom boxes for this application have a 9v battery inside them)? Sorry - well outside my comfort or knowledge zone here..!
Newly minted NPPL (M) pilot thanks to Great Western Airsports, recording my experiences at The Tyranny Of Petty Things and via my online logbook.