Narrowband FM Receiver circuit

[Adie]

Hi group,

Can anyone tell me what it is in the circuit of a NBFM receiver that
makes it different from that of a wideband FM receiver?

 

[Phil Allison]

"Adie"

Can anyone tell me what it is in the circuit of a NEFF receiver that
makes it different from that of a wideband FM receiver?

** The "intermediate frequency" (or IF ) amplification stage has a narrow
operating frequency range compared to that used in a broadcast FM receiver.

Often, a NBFM receiver uses the same type of IF amplifier as used in an AM
band receiver - ie, operates with a centre frequency of 455 kHz with a 10
kHz bandwidth.





......... Phil

 

[Ralph Mowery]

"Adie"

** The "intermediate frequency" (or IF ) amplification stage has a narrow
operating frequency range compared to that used in a broadcast FM receiver.

Often, a NBFM receiver uses the same type of IF amplifier as used in an AM
band receiver - ie, operates with a centre frequency of 455 kHz with a 10
kHz bandwidth.

None of the second statement is true. The IF can be almost any frequency.
The bandwidth of the filter is somewhat larger than 10 khz for a narrow band
FM signal. The FM IF is usually ran at a very high gain to strip the AM
component of signals (usually noise) . This can not be done with an AM
reciever.

The origional question was NBFM not NEFF.

The two main things that come to mind is the bandwidth of the IF filter and
the bandwidth of the detector.

 

[Phil Allison]

"Ralph Mowery"
"Phil Allison"

AM band receiver - ie, operates with a centre frequency of 455 kHz with
a
10 kHz bandwidth.

None of the second statement is true

** It is entirely true.

The IF can be almost any frequency.

** Sure it can be other frequencies - but it IS "often" 455 kHz.

You are just being an ass.

The bandwidth of the filter is somewhat larger than 10 khz for a narrow
band
FM signal.

** NBFM is class of modulation - not a particular bandwidth.

The deviation may be only a few hundred Hz or a few kHz.

You are being a real smartarse now.


Must be one of them smug as hell ham radio pukes.




........ Phil

 

[Don Bowey]

"Ralph Mowery"
"Phil Allison"


** It is entirely true.




** Sure it can be other frequencies - but it IS "often" 455 kHz.

You are just being an ass.





** NBFM is class of modulation - not a particular bandwidth.

The deviation may be only a few hundred Hz or a few kHz.

You are being a real smartarse now.


Must be one of them smug as hell ham radio pukes.

Some of us smug as hell ham radio pukes are well aware of using a NBFM
detector at the end of a "AM" 455kHz I.F. strip. It was still a popular
arrangement into the early 50s.

Don't use a shotgun when a rifle will do the job.

Don

 

[Adie]

Some of us smug as hell ham radio pukes are well aware of using a NBFM
detector at the end of a "AM" 455kHz I.F. strip. It was still a popular
arrangement into the early 50s.

Don't use a shotgun when a rifle will do the job.

Don

Thank you all for your replies. Well at least you've pointed me in the
right direction. I think i have a better understanding now. Its nice
that you all have an opinion but do we really need to resort to
insults? It seems to be commonplace on here. Oh well. Much
appreciated.

Adie

 

[Michael A. Terrell]

Thank you all for your replies. Well at least you've pointed me in the
right direction. I think i have a better understanding now. Its nice
that you all have an opinion but do we really need to resort to
insults? It seems to be commonplace on here. Oh well. Much
appreciated.

Pay no attention to Phil, he's always on the rag. He thinks that his
big mouth makes him a man.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Phil Allison]

"Michael A. Terrell"


** Pay no attention to this Terrell asshole.

He is a paranoid delusional schizophrenic.





......... Phil

 

[Michael A. Terrell]

"Michael A. Terrell"

** Pay no attention to this Terrell asshole.

He is a paranoid delusional schizophrenic.

........ Phil

Don't you have a used vibrator to test, or a damaged toaster to
screw?



--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Rich Grise]

On Thu, 20 Apr 2006 02:07:41 -0700, Adie wrote:
[more trash snipped]

Thank you all for your replies. Well at least you've pointed me in the
right direction. I think i have a better understanding now. Its nice
that you all have an opinion but do we really need to resort to
insults? It seems to be commonplace on here. Oh well. Much
appreciated.

Just put Phalluson in your killfile - it really improves the S/N ratio on
the group.

Cheers!
Rich

 

[Rich Grise]

"Michael A. Terrell"

** Pay no attention to this Terrell asshole.

He is a paranoid delusional schizophrenic.

So, where did you graduate med school? Where did you do your residence in
psychiatric medicine? Inquiring minds want to know.

I will go so far as to say, however, Michael is an inveterate troll-feeder.

Cheers!
Rich