Scan Steps

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jasoyeom

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I'm looking for a chart or other information that shows what the step sizes are in the different frequency ranges. I usually scan by 5khz steps in the 140, 150 & 160 ranges and 12.5khz for anything above 400 mhz. I'm probably missing some frequencies when I'm not scanning with the proper steps.
 

Ubbe

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You can download a user manual for a Uniden scanner. They show a bandplan that should match if Uniden have looked at what FCC have assigned to different users. This is from the Uniden SDS200 manual and what is used when the scanner are set to use auto settings.

DEFAULT BAND SETTINGS
FREQUENCY RANGE MODE STEP (KHZ) BAND

25.0000 26.9600 AM 5 Petroleum Products & Broadcast Pickup
26.9650 27.4050 AM 5 CB Class D Channel
27.4100 27.9950 AM 5 Business & Forest Products
28.0000 29.6800 NFM 20 10 Meter Amateur Band
29.7000 49.9900 NFM 10 VHF Low Band
50.0000 53.9800 NFM 20 6 Meter Amateur Band
54.0000 71.9500 WFM 50 VHF TV Broadcast 2 – 4
72.0000 75.9500 FM 5 Intersystem & Astronomy
76.0000 87.9500 WFM 50 VHF TV Broadcast 5 – 6
88.0000 107.900 FMB 100 FM Broadcast
108.0000 136.9916 AM 8.33 Commercial Aircraft
137.0000 143.9875 NFM 12.5 Military Land Mobile
144.0000 147.9950 NFM 5 2 Meter Amateur Band
148.0000 150.7875 NFM 12.5 Military Land Mobile
150.8000 161.9950 NFM 5 VHF High Band
162.0000 173.9875 NFM 12.5 Federal Government
174.0000 215.9950 FWM 50 TV Broadcast 7 – 13
216.0000 224.9800 NFM 20 1.25 Meter Amateur Band
225.0000 379.9750 AM 25 UHF Aircraft Band
380.0000 399.9875 NFM 12.5 Trunked Military Band
400.0000 405.9875 NFM 12.5 Miscellaneous
406.0000 419.9875 NFM 12.5 Federal Government Band
420.0000 449.9875 NFM 12.5 70 cm Amateur Band
450.0000 469.9875 NFM 12.5 UHF Standard Band
470.0000 512.0000 NFM 12.5 UHF-T Band
758.0000 787.99375 NFM 6.25 Public Service Band
788.0000 805.99375 NFM 6.25 Public Service Band
806.0000 823.9875 NFM 12.5 Public Service Band
849.0125 868.9875 NFM 12.5 Public Service Band
894.0125 960.0000 NFM 12.5 Public Service Band
1240.0000 1300.0000 NFM 25 25 cm Amateur Band

/Ubbe
 

DaveH

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You can download a user manual for a Uniden scanner. They show a bandplan that should match if Uniden have looked at what FCC have assigned to different users. This is from the Uniden SDS200 manual and what is used when the scanner are set to use auto settings.
/Ubbe
This is for Canada which has some differences from U.S. in band usage and step size in VHF band.

Dave
 

DaveH

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To my knowledge Canada does not use 12.5kHz channel spacing anywhere in the 138-144 and 148-174MHz
bands, except 25kHz in the marine band 156/157MHz and 161MHz (exact boundaries can be checked).

The U.S. uses 12.5kHz in 138-144MHz, 148-150.775 and 162-174MHz plus marine band. The rail sub-band of course uses 15kHz/7.5kHz across NA including Canada.

The 2m ham band is 144-148MHz and I would use 5kHz step.

Some places in U.S. such as Alaska appear to use 12.5kHz in the 15x.xxx sub-band.

Canada uses 15kHz/7.5kHz in all sub-bands except marine, with odd exceptions; a few cases of "off-grid"
assignments here and there.The grid "alignment" changes in several places in the 148-174MHz band.

VHF searching with 5kHz steps is not bad but could miss some 7.5kHz assignments; therefore 2.5kHz would
be better (assuing the scanner supports it, most newer ones do), but is going to slow down searching. I generally stick to 5kHz, as something off by 2.5kHz can generally be heard but somewhat distorted. Setting to 7.5kHz
could end up with an alignment issue when crossing these "boundaries".

In the UHF bands, use 12.5kHz or 6.25kHz steps for Canada and U.S.

Dave
 
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jasoyeom

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To my knowledge Canada does not use 12.5kHz channel spacing anywhere in the 138-144 and 148-174MHz
bands, except 25kHz in the marine band 156/157MHz and 161MHz (exact boundaries can be checked).

The U.S. uses 12.5kHz in 138-144MHz, 148-150.775 and 162-174MHz plus marine band. The rail sub-band of course uses 15kHz/7.5kHz across NA including Canada.

The 2m ham band is 144-148MHz and I would use 5kHz step.

Some places in U.S. such as Alaska appear to use 12.5kHz in the 15x.xxx sub-band.

Canada uses 15kHz/7.5kHz in all sub-bands except marine, with odd exceptions; a few cases of "off-grid"
assignments here and there.The grid "alignment" changes in several places in the 148-174MHz band.

VHF searching with 5kHz steps is not bad but could miss some 7.5kHz assignments; therefore 2.5kHz would
be better (assuing the scanner supports it, most newer ones do), but is going to slow down searching. I generally stick to 5kHz, as something off by 2.5kHz can generally be heard but somewhat distorted. Setting to 7.5kHz
could end up with an alignment issue when crossing these "boundaries".

In the UHF bands, use 12.5kHz or 6.25kHz steps for Canada and U.S.

Dave
Thanks Dave. I appreciate the information. I did notice that when scanning the 165 freq range I did catch an US frequency of 165.235 which was 165.2375. It's hard to scan so close to the US border but like you said using 5khz will allow me to catch the offset ones after some corrections.
 

DaveH

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165.2375 is familiar, don't normally hear it but believe it's USBP or whatever they are called now.
P25 enc. also.

I regularly get P25 enc. on 168.850 fairly strong though I'm not really close to the border. Should
be in the DB under US federal or NYS.

Dave
 

jasoyeom

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What is the proper scan step for VHF air and UHF air in Canada/North America? I use 5khz for vhf but understand some areas use a different step size.
 
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nd5y

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What is the proper scan step for VHF air and UHF air in Canada/North America? I use 5khz for vhf but understand some areas use a different step size.
118-137 MHz AM aircraft is mostly 25 kHz channel steps in North America. There is some non-ATC use of 8.33 kHz steps in the US. For more on that see my posts in this thread: 8.33 spacing questions

I don't know if Canada uses 8.33 steps at all. Europe is almost all 8.33 kHz steps now.

225-400 MHz AM aircraft is 25 kHz steps everywhere as far as I know.
 
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Ubbe

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I don't know if Canada uses 8.33 steps at all. Europe is almost all 8.33 kHz steps now.
It's true that most frequencies have been changed to 8.33Khz steps but at my location 95% are still at the old 25KHz frequency and can be scanned with that step size. 3 x 8.33=25KHz. In my area it's more or less 2 high altitude frequencies used at 30.000-40.000ft that could interfere with other countries that use a frequency that doesn't match the old step size.

/Ubbe
 
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