Charlie Tango 11m DX Radio Group Forum
Would you like to react to this message? Create an account in a few clicks or log in to continue.


Welcome to the Charlie Tango DX Group. The home of ALL things Radio - CB, 11m DX, Amateur, PMR446, PLD, Network and Data. We welcome all radio enthusiasts of all knowledge levels. Join today and claim your own unique World Famous CT Call-sign
 
HomeEventsCalendarFAQLatest imagesSearchRegisterLog in
Join in with the fun of the Charlie Tango DX Group Winter 11m Challenge - from December 1st 2024
Navigation
Useful Radio Sites
Log in
Username:
Password:
Log in automatically: 
:: I forgot my password
CT Bill Board





Views This Year
All Time Views
Classified Adverts

Latest topics
» New member intro & Call sign request (Issued)
Noise Blanker, causing noise Icon_minitimeYesterday at 11:21 pm by scubafrique

» Call sign request
Noise Blanker, causing noise Icon_minitimeYesterday at 11:10 pm by vedova

» Server power supply for CB/Ham Radio
Noise Blanker, causing noise Icon_minitimeYesterday at 9:48 pm by Spider281

» Call sign request (Issued)
Noise Blanker, causing noise Icon_minitimeYesterday at 5:23 pm by jlunn01

» Stronger 5/8th Wave Silver Rod?
Noise Blanker, causing noise Icon_minitimeYesterday at 4:31 pm by MM0IMC

» Hello from North Wales. (Issued)
Noise Blanker, causing noise Icon_minitimeYesterday at 1:39 pm by GaryWilson

» POTA hunting
Noise Blanker, causing noise Icon_minitimeYesterday at 9:45 am by VanRougeT4

» South Coast PMR net report
Noise Blanker, causing noise Icon_minitimeYesterday at 5:42 am by Razz229

» Call sign wanted for new member in Bulgaria (Issued)
Noise Blanker, causing noise Icon_minitimeMon Dec 09, 2024 11:37 pm by John123

Keywords
frequency ss9900 list 9900 2023 Mckinley Sirio lincoln software power 2022 anytone yaesu callsign Baofeng sign ALINCO 2011 2024 president display meter chart 6900 antenna call
QRZ Database

 

 Noise Blanker, causing noise

Go down 
3 posters
AuthorMessage
26uk81
Senior contributor
Senior contributor



Call Sign : 26UK81
Posts : 108
Times Thanked : 2
Join date : 2020-06-06
QTH or Location : Oxford
Equipment Used : ss 6900N, AT5555N, President McKinley
Age : 40

Noise Blanker, causing noise Empty
PostSubject: Noise Blanker, causing noise   Noise Blanker, causing noise Icon_minitimeSun May 30, 2021 11:07 pm

Laughing

I was chatting to my mate on UK muppets the other night when some annoying static came up on the channel making working conditions difficult.   Tried changing frequency, my mate put a bit more power on but it made little difference.   I could still hear him though,   so just put up with it for a while.   Just out of curiosity, I hit the NB button (turned it off) and suddenly, crystal clear mod from my mate, all static gone!   I find the NB / ANL very useful on SSB /AM, espectially in the mobile.   But never experienced it actually exacerbating the noise!

Victor likes this post

Back to top Go down
Victor
CT Directors
CT Directors
Victor


Call Sign : 26-CT-3228 / M7VIC
Posts : 6292
Times Thanked : 389
Join date : 2019-11-10
QTH or Location : Bedford
Equipment Used : Various

Noise Blanker, causing noise Empty
PostSubject: Re: Noise Blanker, causing noise   Noise Blanker, causing noise Icon_minitimeMon May 31, 2021 6:38 am

Hi Chris,

I'm not surprised by the results of utilising the Noise Blanker / Automatic Noise Limiter on your radio but when you first discover it for yourself it can be a bit of a shock.

As you rightly point out it is very useful for AM/SSB modes and works best to remove ignition noise from a vehicle mobile installation. Hardly surprising when you consider how old such circuitry is, (decades old designs still in use today!), and those noise scenarios were exactly what they were designed for.

I won't bore you with the history and technical details of such circuitry, (oh believe me, I really could! Wink), but suffice to say you have found a perfect example of where not to use them, namely Frequency Modulation and a noise source other than the repetitive pulses from an ignition system.

In those instances due to the nature of such circuitry you actually degrade the signal path so of course when you turned it off your FM reception actually improved. Seems counter intuitive at first but that's pretty much it in a nutshell.

You'll find other examples of when such circuits improve or degrade your reception such as signal to noise ratios, (SNR). Sometimes turning the RF gain down with the NB/ANL on suddenly improves things because you have brought everything into line where such circuitry performs at it's best. (Another counter intuitive example....turning DOWN the RF gain to improve the reception?!?! Can't be right....yet certainly is. Wink)


It's always nice to make such discoveries to help improve your radio work so take it as a learned bonus.


You can always tell an 'old hand' watching them use a radio, a signal comes in, buttons are quickly switched, the odd twiddle of a knob here or there and the signal is as clear as they can get it. Watching an old timer on an equally old radio is an art performance in itself, they can twiddle those array of knobs and flick switches like a mad professor bringing life forth and sure enough turn that ragged signal into a BBC broadcast reception quality. Smile

It's when they receive someone where they don't have to twiddle a single thing that it's known as an 'armchair copy'.


Anyway, enough of my waffle. 

But suffice to say I've lost count of how many times I've heard, "NB switch? Nah, don't do nuffin mate!", and let out a little sigh.


All the best,
Victor

GaryWilson and Alan Pilot like this post

Back to top Go down
https://www.qrz.com/db/M7VIC
26uk81
Senior contributor
Senior contributor



Call Sign : 26UK81
Posts : 108
Times Thanked : 2
Join date : 2020-06-06
QTH or Location : Oxford
Equipment Used : ss 6900N, AT5555N, President McKinley
Age : 40

Noise Blanker, causing noise Empty
PostSubject: Re: Noise Blanker, causing noise   Noise Blanker, causing noise Icon_minitimeMon May 31, 2021 12:39 pm

Hi Victor

I've always just left the noise blanker on and not given a it a thought.  I always turn it off on FM now.   I have experienced good results from turning down RF gain.   One night, the person I was talking to was almost being wiped out by noise.   WIth the RF gain backed off, it cut out the noise and brought him down to S0 from S7, but I had him on radio 5.

GaryWilson and Victor like this post

Back to top Go down
Northern Crusader
Major contributor
Major contributor



Call Sign : M0GVZ / 26CT1760
Posts : 537
Times Thanked : 35
Join date : 2019-11-13
QTH or Location : IO94SA
Equipment Used : Icom 7300, TS480, President McKinley, Albrecht AE6110, CRT Mike
Age : 54

Noise Blanker, causing noise Empty
PostSubject: Re: Noise Blanker, causing noise   Noise Blanker, causing noise Icon_minitimeWed Jun 02, 2021 5:58 pm

The noise blanker will make the selectivity of a receiver worse meaning you're more susceptible to interfence and bleedover from stations on nearby frequencies.

Turning down RF gain as you state is the best way to do this as it improves the dynamic range of the reciever, attenuating unwanted noise more than wanted signal. ideally you'd wind the RF gain down so the S meter was reading S0 on an empty channel. On AM/SSB just increase the volume knob to compensate for the quieter audio.
Back to top Go down
Sponsored content





Noise Blanker, causing noise Empty
PostSubject: Re: Noise Blanker, causing noise   Noise Blanker, causing noise Icon_minitime

Back to top Go down
 
Noise Blanker, causing noise
Back to top 
Page 1 of 1
 Similar topics
-
» sideband noise
» CRT SS9900 NB (NB Noise blanker) Question
» What the noise blanker does in your radio and why yours probably isn't broken
» Noise on USB 27.305
» Speaker noise

Permissions in this forum:You cannot reply to topics in this forum
Charlie Tango 11m DX Radio Group Forum :: Help and Discussion Forums :: Multimode, Export and Sideband Radio-
Jump to: