CW

GB46

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544
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British Columbia, Canada
VORs are in the usual aviation band. Some near me are 117 and 112.8 MHz. NDBs, however, are in the kHz to low MHz range.

For BC, look at CYWL (Williams Lake). To the northwest is a VOR on 113.6. Also in BC, is CBBC (Campbell Lake), which has an NDB to the east on 325 kHz.

The way I can easily remember we use the NDB receiver in our local aircraft to listen to local AM stations while moving about.
Thanks for the clarification. So I've been using the wrong term; what we have on 290 kHz is an NDB. A lot of them are about to be decommissioned in Canada.
 

belvdr

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Thanks for the clarification. So I've been using the wrong term; what we have on 290 kHz is an NDB. A lot of them are about to be decommissioned in Canada.
I'm not sure how long the NDBs will be viable in the US. I know if you have an NDB receiver in the aircraft during your checkride, you better know how to use it. Realistically speaking, I would venture it's only used for nostalgic purposes these days. GPS/GLONASS is much easier to use.
 

majoco

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New Zealand
Let's tidy things up here - there is quite a bit of misinformation. "CW" stands for "carrier wave" which is the single frequency which is modulated to give the voice/music you hear on the AM broadcast band - called "amplitude modulation". Now if you turn the carrier wave on and off to send the characters of the alphabet and numbers of the morse code you can send messages with a very narrow bandwidth. However in a normal receiver you cannot hear the tone - so you need to mix the received signal with one generated in the receiver but not quite on the same frequency so you get the 'beat note' of the two signals making it audible - all you need to do now is memorise the morse code!
Navigation beacons for aircraft have three types, NDB's - non-directional beacons in the frequency band below the broadcast band, say 150kHz to 400kHz, VOR's - VHF omni-range in the band 108 to 118 MHz - these beacons radiate two signals which enable you to determine your bearing from the station and ILS's - the Instrument Landing System - the localiser part also works in the 108 to 118MHz VHF band and enables the pilot to find the centre line of the runway. Now all these signals have a unique identification of two or more amplitude modulated morse code letters so if you have a receiver to cover these frequencies then you can hear the 'ident'. The NDB's just have the ident signal so that is all you will hear but the VOR's and ILS's have other signals too - you may hear a wobbly tone on the VOR signal and two tones 90Hz and 150Hz on the localiser. You have to be quite close to the airport to hear these signals.
Now it gets tricky. The NDB signal has a carrier and the modulating tone. The modulating tone, usually 400Hz or 1000Hz, is mixed with the carrier frequency to produce three parts, the original carrier, the lower sideband and the upper sideband. For instance if the carrier is 300kHz and the modulation is 1kHz then the LSB is 299kHz and the USB is 301kHz - but the information carried in the LSB and the USB is identical and the carrier really doesn't do anything - so if you just transmit the USB and if you mix that with a ''carrier'" in the receiver you can hear the tone again - just like the CW signal! There are great advantages to this method of communication - to much to go into here.
Hope this all makes sense!
 

danesgs

Member
Joined
May 21, 2008
Messages
254
Good to know. What are your recommendations for SSB receivers? I have no clue about their prices, but would probably want something in the $75-100 range.
You will get as many replies to that question as members that are here. What is best for your price range and being new is to research the net and look at reviews on places like SWLing.com. Some are better than other others for CW in that range but having had a number of radios, I usually research the reviews first before I plop down the money. The main thing is that a radio with SSB will have a dedicated control that allows you to vary the CW signal to hear it better. It will be marked on the radio as SSB. Hope this helps a bit.
 

JAF27

WRJT427
Joined
Oct 13, 2020
Messages
41
Location
Lower Manhattan, New York City, New York
You will get as many replies to that question as members that are here. What is best for your price range and being new is to research the net and look at reviews on places like SWLing.com. Some are better than other others for CW in that range but having had a number of radios, I usually research the reviews first before I plop down the money. The main thing is that a radio with SSB will have a dedicated control that allows you to vary the CW signal to hear it better. It will be marked on the radio as SSB. Hope this helps a bit.
I will take a look! Do you know what this CW control is called, so I can make sure the one I buy has this feature? Thanks for the help!
 

JAF27

WRJT427
Joined
Oct 13, 2020
Messages
41
Location
Lower Manhattan, New York City, New York
Let's tidy things up here - there is quite a bit of misinformation. "CW" stands for "carrier wave" which is the single frequency which is modulated to give the voice/music you hear on the AM broadcast band - called "amplitude modulation". Now if you turn the carrier wave on and off to send the characters of the alphabet and numbers of the morse code you can send messages with a very narrow bandwidth. However in a normal receiver you cannot hear the tone - so you need to mix the received signal with one generated in the receiver but not quite on the same frequency so you get the 'beat note' of the two signals making it audible - all you need to do now is memorise the morse code!
Navigation beacons for aircraft have three types, NDB's - non-directional beacons in the frequency band below the broadcast band, say 150kHz to 400kHz, VOR's - VHF omni-range in the band 108 to 118 MHz - these beacons radiate two signals which enable you to determine your bearing from the station and ILS's - the Instrument Landing System - the localiser part also works in the 108 to 118MHz VHF band and enables the pilot to find the centre line of the runway. Now all these signals have a unique identification of two or more amplitude modulated morse code letters so if you have a receiver to cover these frequencies then you can hear the 'ident'. The NDB's just have the ident signal so that is all you will hear but the VOR's and ILS's have other signals too - you may hear a wobbly tone on the VOR signal and two tones 90Hz and 150Hz on the localiser. You have to be quite close to the airport to hear these signals.
Now it gets tricky. The NDB signal has a carrier and the modulating tone. The modulating tone, usually 400Hz or 1000Hz, is mixed with the carrier frequency to produce three parts, the original carrier, the lower sideband and the upper sideband. For instance if the carrier is 300kHz and the modulation is 1kHz then the LSB is 299kHz and the USB is 301kHz - but the information carried in the LSB and the USB is identical and the carrier really doesn't do anything - so if you just transmit the USB and if you mix that with a ''carrier'" in the receiver you can hear the tone again - just like the CW signal! There are great advantages to this method of communication - to much to go into here.
Hope this all makes sense!
Thanks for the help. As in CW, we are referring to continuous wave, or morse code. Please note that I am new to radio, but I am aware of many aviation topics you discussed. However, I guess the modern radio avionics were so easy that I didn't quite understand all aspects of radio in the sky. :)
 

jwt873

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Dec 1, 2015
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Woodlands, MB
You've never mentioned what scanner you have. You might have the capability to receive CW or SSB, (but it's unlikely).

When searching for a low priced receiver that will receive CW and single sideband (SSB) don't overlook one of those RTL software defined radio dongles that you plug in to a computer. There is a lot of info on this forum on how to set one up. Software Defined Radio

I use CW to communicate on the ham radio 50 Mhz, 144 Mhz and 432 Mhz bands. I often scan the 28 Mhz and 50 Mhz bands and listen for for CW propagation beacons. When I hear them, I log them on DX maps.com DX cluster / DX spots - dxwatch.com When these bands are open you can hear VHF signals from great distances.

There are also CW beacons on the higher bands (Here's a list of them going from 144 Mhz to 10 gHz) VHF/UHF BEACONS by WZ1V

Also, here's a list of ham radio frequencies where CW is used. I only went to 432 Mhz, but note, you'll hear very little when tuning over 50 Mhz.

Code:
28.000-28.070     CW
28.150-28.190     CW
28.200-28.300     Beacons

50.0-50.1         CW, beacons
50.1-50.3         SSB, CW

144.05-144.10     General CW and weak signals
144.10-144.20     EME and weak-signal SSB

222.10-222.15     Weak-signal CW & SSB
222.05-222.06     Propagation beacons

432.07-432.10     Weak-signal CW
432.30-432.40     Propagation beacons
 

GB46

Very radioactive
Joined
Feb 4, 2017
Messages
544
Location
British Columbia, Canada
I'm not sure how long the NDBs will be viable in the US. I know if you have an NDB receiver in the aircraft during your checkride, you better know how to use it. Realistically speaking, I would venture it's only used for nostalgic purposes these days. GPS/GLONASS is much easier to use.
I think the NDBs that will remain in Canada are located where aircraft/airports haven't set up the most up-to-date navigational aids so far. I can hear three in my general vicinity that might remain plus a couple of them farther north that are close to an international airport and could possibly be decommissioned. It's a slow process, however. I read about the decision months ago, but I doubt if anything has been done yet.
 

GB46

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Location
British Columbia, Canada
No -- after reviewing NavCanada's document I see I was wrong again. All the NDBs that I can currently hear are recommended for eventual decommissioning. No great loss on my end, anyway, because once I've heard and identified them, listening to their CW IDs over and over can get pretty boring after a minute or so.

I know where the towers are, and have driven past one of them many times. It's situated on a nice piece of property with a "no trespassing" sign in English and French in a residential neighborhood, right in between two houses. If the tower is abandoned and left on the property it might be just the place for a ham to build a house!
 

popnokick

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Northeast PA
And you think this one would be good to listen to CW with?
For $600 - $700.... Yes, it will receive CW and all the other modes / bands listed in the prior post. Well out of your $75-100 price range but it will do what you want.
 

GB46

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Messages
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Location
British Columbia, Canada
going by the ham radio band plans, it looks like the majority of CW is below 25.000 MHz...
True. In fact, the only ham CW I've heard recently has been on 80, 40 or 20 meters; in other words, no higher than about 14.1 Mhz. Even on those bands I hear relatively little CW except during contests. When conditions are favorable I'll hear some voice activity, but otherwise most of what I pick up is in the digital modes, esp. FT8, where there's lots of activity all day long. That, too, requires SSB.
 
Last edited:

JAF27

WRJT427
Joined
Oct 13, 2020
Messages
41
Location
Lower Manhattan, New York City, New York
You've never mentioned what scanner you have. You might have the capability to receive CW or SSB, (but it's unlikely).

When searching for a low priced receiver that will receive CW and single sideband (SSB) don't overlook one of those RTL software defined radio dongles that you plug in to a computer. There is a lot of info on this forum on how to set one up. Software Defined Radio

I use CW to communicate on the ham radio 50 Mhz, 144 Mhz and 432 Mhz bands. I often scan the 28 Mhz and 50 Mhz bands and listen for for CW propagation beacons. When I hear them, I log them on DX maps.com DX cluster / DX spots - dxwatch.com When these bands are open you can hear VHF signals from great distances.

There are also CW beacons on the higher bands (Here's a list of them going from 144 Mhz to 10 gHz) VHF/UHF BEACONS by WZ1V

Also, here's a list of ham radio frequencies where CW is used. I only went to 432 Mhz, but note, you'll hear very little when tuning over 50 Mhz.

Code:
28.000-28.070     CW
28.150-28.190     CW
28.200-28.300     Beacons

50.0-50.1         CW, beacons
50.1-50.3         SSB, CW

144.05-144.10     General CW and weak signals
144.10-144.20     EME and weak-signal SSB

222.10-222.15     Weak-signal CW & SSB
222.05-222.06     Propagation beacons

432.07-432.10     Weak-signal CW
432.30-432.40     Propagation beacons
I have a Uniden BC365CRS
 

WB9YBM

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Joined
May 6, 2019
Messages
444
Location
Niles, IL
You will get as many replies to that question as members that are here. What is best for your price range and being new is to research the net and look at reviews on places like SWLing.com. Some are better than other others for CW in that range but having had a number of radios, I usually research the reviews first before I plop down the money. The main thing is that a radio with SSB will have a dedicated control that allows you to vary the CW signal to hear it better. It will be marked on the radio as SSB. Hope this helps a bit.
Actually a "CW" position on the radio's mode control automatically shifts the receive frequency by 1 KHz so a cw signal is heard as a "beep" instead of as a dead momentary carrier...
 

belvdr

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Aug 2, 2013
Messages
883
All this talk about CW has me and my son wanting to learn. I've read that having a practice oscillator that we can use to "send" to each other helps. I'd like to practice on an iambic paddle, as I can see me using that long term.

However, it brings up two questions:
  1. Lame, I know, but in the movie Phenomenon, Nate uses what I would call an iambic paddle, but it looks like a straight key. Are these better than the side-by-side paddles?
  2. Anyone have any experience with any of the practice osciallators?
I could very well not fully understand what a straight key is, mind you.
 
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Boombox

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Joined
Sep 2, 2012
Messages
900
For CW just get a good portable with SSB. Any radio that has SSB will decode CW. And yeah, the HF ham bands is where you'll hear most of it anymore. There used to be maritime CW, but that is mostly gone. Some maritime HF stations put out CW 'markers' (holding the frequency with a CW call), but they are few and far between. Most CW I've heard over the past decade was 40 meters and 20 meters ham band CW (7000-7100 khz or so, 14000-14150 khz or so).
 
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