having trouble transmitting with 430

i am not getting any audio out on tx. only some unreadable garbled noise. it is receiving fine. any ideas were to start with this issue?

turbo said:

i am not getting any audio out on tx. only some unreadable garbled noise. it is receiving fine. any ideas were to start with this issue?

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Assuming you have checked the radio I would start with your microphone, then the audio panel then the wiring between the microphone and the audio panel. Cheapest easiest solution 1st.

Same issue

We had the same issue with a 430 in a Bonanza for years. Sent it back to Garmin twice and it would do the same thing again. It would normally transmit clear for the first couple of transmissions and then become unreadable after that. We tried a loaner 430 which worked perfect. Never did figure it out.

If it worked before, first check that the power connection is tight on the breaker.

In other words, if it once worked and still works on receive, one cause could be a high resistance power contact that under load presents a significant voltage drop at the radio.

Carl

Get a SWR meter and test your antenna cable.

I had the same problem with my 430. It will receive fine but transmit may be garbled with a poor antenna or cable to the antenna. In my case, the antenna cable was not secured well at the base of the whip antenna. As a result, the antenna cable suffered repetitive stress right where it entered the antenna connection. In my case, the cable failure resulted in the symptoms you describe.

And another thing...
Stop transmitting on that radio. If it is a bad antenna cable, you could damage your transmitter if you continue transmitting on it with high SWR.

sounds like what happened to me

working fine one day and nothing the next. A local Garmin dealer bench tested it for free and confirmed no transmission. It went back to Garmin, and they replaced the transmitter for their standard flat rate.

Grbled noice when try to transmit

If you have audio pannel or intercom thee is small part on mike input called low pass filter it is small rc sirqut in my case PMA8000 had failuer of capacitor of the filter and i simply removed the filter to avoid this problem in future
Same filters most likely used in 430 to diagnose connect your mike directly to 430 input and try to transmit if you need pictures let me know

vluvelin said:

If you have audio pannel or intercom thee is small part on mike input called low pass filter it is small rc sirqut in my case PMA8000 had failuer of capacitor of the filter and i simply removed the filter to avoid this problem in future
Same filters most likely used in 430 to diagnose connect your mike directly to 430 input and try to transmit if you need pictures let me know

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Many intercoms - including the PMA8000 - allow you to bypass the intercom by just turning the power off. So easy to check.

Re-seat the radio, pull it partially out, then re-seat it using the install manual instructions to determine if it is fully engaged in the tray.
Cheap, easy thing to try.
Tim Andres

BobTurner said:

Many intercoms - including the PMA8000 - allow you to bypass the intercom by just turning the power off. So easy to check.

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Not in this case the default emergency signals in PMA8000 are passing through series of relays that switch to sertain posision when power is off the low pass filter is not bypassed it is passive component and problem will not go away
The only way is compeatly remove audiopannel or intercom

On PMA8000 they say low pass filte never fails i have proof it does