Thursday, 13 March 2014 01:53

Ham Radio Simplex Frequencies for 2 Meter / 70cm and more...

Written by 
Rate this item
(4 votes)

Reference for VHF/UHF amateur radio FM simplex frequencies for 6 Meter / 2 Meter / 1.25 meter / 70cm

I've compiled some suggested channels and frequencies to use on these bands

Try something new, these frequencies should be stored in every HT or mobile.  I enjoy messing around with VHF/UHF radios but repeaters usually bore me.  These frequencies are compiled from the ARRL "official" band plan as well as other forums and sites I have come across over time.

 

It's a good idea to ensure when using simplex, although there aren't designated channels, that you are spaced out within the frequency band in a way to help eliminate adjacent interference. 

I know there's other bands from 902 MHz and up but I don't have any experience with those bands and these are the most popular.  Keep in mind working simplex on an HT with 5 watts is not only challenging but can be sometimes impossible at anything other than very short distances. Height and antenna can work wonders, experiment, try different locations, build an antenna or two and have fun!

I am planning on doing some experimenting specifically in the 2m band soon and in my research to find the proper frequencies to use I found it a bit challenging to find specific simplex channels to use for 2m FM.  I decided to consolidate a list of what I found to be the correct frequencies to use to avoid causing any interference to others in the band as well as having some fun with simplex.

 

6 Meters (50 - 54 MHz)

ARRL Band Plan MHz
FM Simplex 52.020
FM Simplex 52.040
FM Simplex Primary 52.525
FM Simplex Secondary 52.540
FM Simplex Remote Base 53.000
Misc Sources  
FM Simplex 50.300
FM Simplex 51.1 - 52.0
FM Simplex 51.500
FM Simplex 51.600
FM Simplex 52.490
FM Simplex 52.510
FM Simplex 53.520
FM Simplex 53.900

I personally do not have any experience using FM simplex on the 6 meter band, I just wanted to try to consolidate the most accurate information I was able to find regarding FM simplex operation.  Different frequencies may be more popular than others in various regions but following the above ARRL band plan for FM simplexfrequencies should be a good place to start.

 


2 Meters (144 - 148 MHz)

ARRL Band Plan MHz
FM Simplex *146.40 - 146.58
FM Simplex Calling Frequency 146.52
FM Simplex 147.42 - 147.57
30kHz channel spacing
 
FM Simplex 146.430
FM Simplex 146.460
FM Simplex 146.490
FM Simplex (Calling Frequency) 146.520
FM Simplex 146.550
FM Simplex 146.580
FM Simplex 147.420
FM Simplex 147.450
FM Simplex 147.480
FM Simplex 147.510
FM Simplex 147.540
FM Simplex 147.570

 *146.40 Maybe used as a repeater input in certain regions per the ARRL bandplan so I decided not to include this in the 30kHz channel spacing list.

2 meter FM simplex channels can vary significantly in different regions.  Using the ARRL frequency range allocated for FM simplex is a starting point but 15, 20, or 30kHz spacing is the million dollar question. Many areas use 15kHz spacing, some states (west of the Mississippi?) use 20kHz spacing.  While some areas use 30kHz spacing between channels, this method still provides plenty of channels and helps to eliminate any interference from strong adjacent channels.  The possible problem that can happen with this is if you choose to use 15kHz or 30kHz spacing but the local area may have chosen to use 20kHz spacing you can potentially step over one another.  Since the FM simplex channels spacing is not regulated a good rule of thumb is to ask some local hams, if this doesn't work, stay within the designated ARRL frequency range for FM simplex and as always listen first before transmitting.

I choose to use the 30kHz spacing for the list above for several reasons.  It seems from what I could find that 15/30 spacing model is more popular than the 20kHz spacing and 15kHz in my opinion is too close for 2m FM and can cause you to step over adjacent channels.  I took two different brand HTs (Kenwood TH-D72A and Baofeng F-11 (almost the same as a UV-5R)) to see if I would have interference using the 15kHz spacing model and I did.  The experiment was not very scientific and one day I would like to use my SDR to actually see the signals and do some various tests with different distances but that will be at a later date.  I did find 20kHz spacing to be acceptable as far as not causing interference but again it appears the 15/30 spacing is the more popular choice with 2 meters.  I also found that the start/end frequencies of the ARRL simplex frequency range are 30kHz apart from the next frequency range for repeater inputs/outputs.

 

 

1.25 Meters (222 - 225 MHz)

ARRL Band Plan MHz
FM Simplex 223.40 - 223.52
Misc Sources  
FM Simplex 223.42
FM Simplex 223.44
FM Simplex 223.46
FM Simplex 223.48
FM Simplex Calling Frequency 223.50
FM Simplex 223.52

Notice the 20kHz spacing between channels for the 1.25M band.  I have not used this band myself but this appears to be the most popular spacing to follow in this band.

 

70 cm (420 - 450 MHz)

ARRL Band Plan MHz
FM Simplex Calling Frequency 446.000
Misc Sources  
FM Simplex 446.500
FM Simplex 447.000

Simplex on 70cm is even less popular but these frequencies seems to be the more popular ones around to use.

 

 

References:

http://www.arrl.org/band-plan

http://www.mrc.gen.mn.us/010902/FMSIMP.htm

https://groups.google.com/forum/#!topic/pnwvhfs/H-2qiOVth7Y

http://www.bandplans.com/index.php?band=6

http://www.hamuniverse.com/simplexoperating.html

http://www.n5lxi.com/ham/2meter_simplex.html

 

Read 28057 times Last modified on Thursday, 24 September 2015 15:14
Algis Salys

Creator and owner of algissalys.com.  Linux enthusiast, electronics tinkerer, and likes to spend time in the workshop building and creating new projects.