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CDF modulation?

Posted: Wed Mar 18, 2009 10:24 am
by w6kru
The comm guidelines from the firescope website shows most of the CDF freqs. to be using wide FM modulation? Is that for real? I have volume issues when I set my 396T that way.

Re: CDF modulation?

Posted: Wed Mar 18, 2009 10:10 pm
by SkipSanders
'Wide FM' as in, regular old NFM. 'Narrow FM' now means 6.25 KHz channel spacing.

Wide FM to your scanner is FM Broadcast/Non-Digital TV Audio, 75 KHz deviation.

Re: CDF modulation?

Posted: Wed Mar 18, 2009 10:17 pm
by 800
SkipSanders wrote:'Wide FM' as in, regular old NFM. 'Narrow FM' now means 6.25 KHz channel spacing.

Wide FM to your scanner is FM Broadcast/Non-Digital TV Audio, 75 KHz deviation.
Partially correct [not 6.25 yet]. Narrow in the VHF / UHF community is a 12.5 kHz channel (compared to the existing 25 kHz channels).
The 6.25 kHz efficiency implementation date was postponed indefinitely.

Don

Re: CDF modulation?

Posted: Wed Mar 18, 2009 11:18 pm
by w6kru
Thanks Skip. Thanks Don. It looks like I should just set the modulation to FM for these freqs. They aren't wide as in broadcast FM and they aren't narrow either. I searched the owners manual, an online "easy manual", and a couple of reviews for the BW on the WFM, FM, and NFM settings and couldn't find that answer. In hindsight it wouldn't be WFM so FM makes the most sense.