Output Volume on 5 and 7 pin Autocom systems

[John Bentall]

I recently mentioned that during visit to the Autocom factory for some remedial work on the Pro-M1 installation in my R1200RT with radio, I declined the offer of a free upgrade to a Pro-M7 on the grounds that volume would be increased by 100% into my perfectly adequate speakers and even-more-sensitive earplug speakers.

I would like to correct this statement in so far as the latest 7 pin systems have double the voltage to the speakers (compared to the old 5 pin systems) giving about 300% increase ONLY when set to high for use with conventional earplugs. When set to normal, they have exactly the same output to the speakers as the old 5 pin systems.

 

The special monitor earplug adaptor leads (part 26 for 7 pin or part 27 for 5 pin) have further attenuation resistors fitted to reduce the volume/voltage to the tiny in-ear speaker that are built into the monitor earplugs.

 

So the output levels for intercom speech with either 5 pin or 7 pin systems are the same with monitor earplugs when used via parts 26/27. Music, transceiver, phone, GPS, radar etc all normally have their own volume controls that are set according to personal preference whether one uses conventional, monitor or indeed no earplugs.