Gents,
I have a Dynon 180 and a Flightcom 403 intercom. I have been testing the Dynon alarms which are connected through the Aux input of the 403.
I made a ?junction? to feed the Alarms, music and Garmin 496 alerts into the intercom. Currently the 496 isn?t connected up. I used the schematic provided by Dynon to input the mono alarms into the stereo intercom. I tested it with a potentiometer and settled on 15K ohm resistor.
When testing the system I notice a slight HUM in the background when no music or alarm is turned on. However when I turn on the IPOD (not playing music) the HUM goes away (something to do with impedance). I also notice the alarm volume level drops when the IPOD is connected and not playing. The only items powered up during the test were the Dynon and the intercom.
It sounds like A/C HUM but I am running off the battery. If I shut the Dynon off the HUM goes away. I disconnected the alarm pins at my "Aux input junction" to see if it was my audio wiring was causing the problem but the HUM went away. I even shut off my florescent lights to see if that was the cause, but it wasn?t.
With only the Dynon and intercom powered up there aren?t a lot of electrons moving throughout my wiring so I am a bit confused. The HUM is definitely coming from the alarm inputs and the Dynon.
I am not an electrical guru so if there is anyone who can help me stop this unwanted HUM, It would be appreciated. Maybe a capacitor along with the resistors?
I have a Dynon 180 and a Flightcom 403 intercom. I have been testing the Dynon alarms which are connected through the Aux input of the 403.
I made a ?junction? to feed the Alarms, music and Garmin 496 alerts into the intercom. Currently the 496 isn?t connected up. I used the schematic provided by Dynon to input the mono alarms into the stereo intercom. I tested it with a potentiometer and settled on 15K ohm resistor.
When testing the system I notice a slight HUM in the background when no music or alarm is turned on. However when I turn on the IPOD (not playing music) the HUM goes away (something to do with impedance). I also notice the alarm volume level drops when the IPOD is connected and not playing. The only items powered up during the test were the Dynon and the intercom.
It sounds like A/C HUM but I am running off the battery. If I shut the Dynon off the HUM goes away. I disconnected the alarm pins at my "Aux input junction" to see if it was my audio wiring was causing the problem but the HUM went away. I even shut off my florescent lights to see if that was the cause, but it wasn?t.
With only the Dynon and intercom powered up there aren?t a lot of electrons moving throughout my wiring so I am a bit confused. The HUM is definitely coming from the alarm inputs and the Dynon.
I am not an electrical guru so if there is anyone who can help me stop this unwanted HUM, It would be appreciated. Maybe a capacitor along with the resistors?