Hi,
I have been searching for a perfect headset for 48 hour contest operation
and found Bose A20 aviation headset being highly praised by pilots for
comfort as well as noise cancelling. Looks like an excellent product.
I wonder if it is usable for ham purposes with my Yaesu radios and
Microham keyers.
Maybe someone has experience of using aviation headsets?
And I am afraid the impedances of headphones and mic would be a problem?
The A20 manual
(http://products.bose.com/pdf/customer_service/owners/og_a20_owners_en.pdf
) says that:
Microphone (Electret) Bias required: 8 to 16 VDC through 220 to 2200 Ohms.
Sensitivity: Varies depending on bias and AC radio input impedance.
Typical output is 600 mV at 114 dB SPL. To assure proper modulation of the
radio, it is recommended
that an avionics technician adjusts its input to match the output of the
microphone.
Microphone (Dynamic) Impedance: 5 Ohms
Sensitivity: Equivalent to M-87/M-101
The 5 ohm impedance is drastically different from ca 600 ohm level of
Yaesu and Heil dynamic mics. Would this be usable at all for our
purposes??
Or maybe the electret mic with modification could be used for Yaesu
radios?
About headphones the manual says:
Impedance Monaural mode: 160 Ohms ON and OFF
Stereo mode: 320 Ohms ON and OFF
I hope someone who knows more about headphones and mics can help me find
the answer if this headset can be used.
73
Tonno
ES5TV
p.s. any other recommendations on perfect heatsets (that would not kill
the ears in 48 hours like Heil) are also very welcome.
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