Obscure question about FM deviation

Michael N3LI · January 27

Hi all,

When I am running my transverter for 2 meters, I cannot seem to get a decent deviation level. People have noted that the audio level is weak. Mic is a Heil ProSet Elite, HC6. Even running the mic level at 100, and a few attempts at messing with compression, and I haven't tried turning the equalizers up more than the default, but can't imagine having to do that, something is off somewhere.

The mic audio works FB on SSB. and normally runs around 60, so I know it works normally. It also works for APRS and Packet on 2 meters - Digu-SSB

Mike-VA3MW · January 30

Hi MIchael

Not the Mic Gain setting. That is different for every operator. The way you tell what it should be set to is by watching the level meter.

This should be peaking to just below 0db.

Have a look at this video right at the point that I set it for. About 2 minutes in. It explains the Mic gain.

https://youtu.be/GdFeTzPo14w?si=3BMapgfLg5J6CAfD&t=174

KD0RC · January 27

Hi Michael, are you using FM (5kHz deviation) or NFM (2.5 kHz deviation)?

Neil D Friedman N3DF · January 27

Michael—what transverter are you running? Have had no issues with deviation using my Q5.

Michael N3LI · January 29

https://community.flexradio.com/discussion/comment/20608814#Comment_20608814

I'm using FM. Interesting point/question though, It would be sufficient deviation for narrow. I'll have to fire it up and check again.

Michael N3LI · January 29

https://community.flexradio.com/discussion/comment/20608815#Comment_20608815

I'm using one of the Transverter Store transverters, from the fellow in Ukraine.

Mike-VA3MW · January 29

What is the Mic Level Meter show?

Michael N3LI · January 30

https://community.flexradio.com/discussion/comment/20608845#Comment_20608845

I'm running at 55, which seems to be a good setting for SSB.

KD0RC · January 30

Hi Michael, The level of the mic is very dependent on the mic and the person speaking. What Mike was asking about is the mic level meter. The peak indicator (the little rectangle) should be up above -10 dB when you speak, but never over 0 dB where it turns red. I try to keep mine somewhere around -5 dB. For my voice and Heil HM-12 mic my mic level is at 48.

If your peak indicator is much below -10 dB, I think you will experience low audio output.

To see the level meter even when you are not transmitting, in SmartSDR, go to Settings, Radio Setup, Phone/CW tab. Enable Level Meter During Receive.

EDIT: Sorry, I didn't see Mike's response in the Accepted Answer spot above...

Ken Wells · January 30

You might also want to create a different Mic Profile for FM with Low-Cut = 200 or 300 and High Cut = 2700 or 3000 so that your FM audio is not overpowered by bass frequencies (which are blocked by most FM Repeaters anyway, due to CTCSS usage.) FM often needs a different treatment for TX EQ..... Less treble boost than a SSB DX Profile and not as much bass as some use for a SSB "Rag Chew" profile.

PROC should be used at NORM if at all (it is not required on FM, but can give a little boost to the audio.... if used in moderation.)

Michael N3LI · January 31

https://community.flexradio.com/discussion/comment/20608887#Comment_20608887

I'll give that a try - Thanks, Ken!

Obscure question about FM deviation

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