Aqui encontre el TM del H161
http://dev.n8it.org/acs/documents/161.pdf
Hay diferencias entre el /U y A/U
Headset-Microphone H-161A/U is interchangeable
with the H-161/U, but the H-161/U cannot be substituted
for the H-161A/U. Connector, Plug, Electrical
U-182/U on the H-161A/U interphone cord
has been rewired to include a ground wire to pin A
(fig. 5-2). This change was made to help eliminate
background noise. The H-161A/U uses a chest
strap, instead of the clothing clip used on the H-
161/U (figs. 1-1 and 1-2), to hold the chest switch
assembly close to the user’s chest.
Funcionaran ambos en la PRC25??