APX APX Decode MDC Trailing Edge

[Jl942264]

Hi all,
I'm trying to decode MDC trailing edge on my APX 900 and 7000. I have PTT ID Display set to Dispatch and Scan its set to 6 and font size 4. They both will decode leading edge, any ideas as to why it wont decode trailing.... thanks all!

 

[cpg178]

What is the End of Voice timer set to? If it is at 0 it wont show trailing edge, set it to 1 or 2 seconds.

 

[Jl942264]

What is the End of Voice timer set to? If it is at 0 it wont show trailing edge, set it to 1 or 2 seconds.

I believe I had it at 3 or 4

 

[cpg178]

As long as it is not at 0 the OP should be able to see trailing IDs. Since he can get leading IDs it means that he has the signaling system added to his personality correctly, so my next guess would be the EOV Timer

 

[Jl942264]

As long as it is not at 0 the OP should be able to see trailing IDs. Since he can get leading IDs it means that he has the signaling system added to his personality correctly, so my next guess would be the EOV Timer

It’s not at zero, just verified I’ve tried literally every number on the EOV any other ideas?

 

[Tech21]

Do you have it set for pre and post?

 

[Jl942264]

Do you have it set for pre and post?

Just post.

 

[GTR8000]

You have PTT ID enabled in each conventional personality, correct?

 

[Jl942264]

You have PTT ID enabled in each conventional personality, correct?

Not in all of them, just the one that’s active

 

[Tech21]

If you PM me your codeplug, I can look it over and see if anything stands out.

 

[Jl942264]

If you PM me your codeplug, I can look it over and see if anything stands out.

Will do

 

[Tech21]

I'm not seeing anything that stands out. You have the MDC set to transmit on trailing which is when you release the PTT, the MDC ID is transmitted at the end instead of the beginning. Leading sends it at the beginning and both sends it at both the beginning and end of the transmission. The fact that if you set it to leading or both, you see the PTT-ID on the receiving radio means everything else is set correctly and it just sounds like a timing issue.

Display is set to Dispatch, try dispatch and scan.

Try setting the MDC system pretime to 0 milliseconds.

End of voice timer is set to 4 which is plenty to receive and MDC ID.

SAVE A CLEAN COPY OF THE CODEPLUG BEFORE MAKING THESE CHANGES AND TESTING.

 

[GTR8000]

If the radios are in scan, and you don't have PTT ID Display set to Dispatch and Scan, you're not going to see the ID/alias.

Try setting the MDC system pretime to 0 milliseconds.

That won't make a difference for trailing edge MDC, as that parameter determines the amount of time between key up and transmitting the leading edge MDC burst. In fact, your suggestion would be the opposite of what you would want to do if the ID weren't coming across another radio; you'd want to increase the gap between key up and MDC, not decrease it.

 

[Jl942264]

If the radios are in scan, and you don't have PTT ID Display set to Dispatch and Scan, you're not going to see the ID/alias.



That won't make a difference for trailing edge MDC, as that parameter determines the amount of time between key up and transmitting the leading edge MDC burst. In fact, your suggestion would be the opposite of what you would want to do if the ID weren't coming across another radio; you'd want to increase the gap between key up and MDC, not decrease it.

I have it now at dispatch and scan… no dice. Seems like it’s working on leading or both. I’ve tried every single number on the EOVT. The channel is talk around could that make a difference..

 

[GTR8000]

By "talkaround" I assume you mean it's just a normal simplex channel...same frequency and tone for TX/RX. No that shouldn't make any difference, the MDC will work just fine in simplex mode.

When you say it works when set to leading and trailing, are you seeing the ID come across the receiving radio twice? Key up, observe leading ID on the receiving radio, hold TX for 10 seconds, de-key, observe trailing ID on the receiving radio. If you're not seeing both, then it's not working correctly, in particular the trailing squawk.

 

[Jl942264]

Got it working don’t ask what I did… I changed the IDs on both radios and boom

 

[Tech21]

...

 

[KevinC]

I believe I had it at 3 or 4

Any special reason you have 2 accounts?

 

[Tech21]

Supreme Leader is after you now...lol.

 

[KevinC]

Supreme Leader is after you now...lol.

I’m everywhere Focker.