Frequency Utilization Plans (FUPs) are a great way to help organize and deconflict radio frequency and channel use not only for the Amateur Radio Service (HAM Radio), but for other radio services as well including the Citizens Band Radio Service (CBRS, better known as “CB”), the Multi-Use Radio Service (MURS), the Family Radio Service (FRS), and the General Mobile Radio Service (GMRS). While adhering to a FUP is not mandatory, it is certainly Good Form and is a great way to enhance the efficient and productive use of our radio spectrum.
The Anchorage Amateur Radio Club has developed a FUP for the HAM bands based on the excellent work of the Southeastern Repeater Association. We are also working with local organizations and agencies who use the other radio services (CB, MURS, FRS, and GMRS), to develop FUPs for each of these appropriate for the South Central Alaska area.
We also provide information about MURS, FRS, and GMRS use of “privacy codes”. Manufacturers refer to these as “Privacy Codes”, “Private Line”, “PL”, Interference Eliminator Codes”, “Quiet Codes”, and maybe other names or terms. What do these codes do? They cause your radio to not open its squelch (not let you hear the other radio’s transmission) unless the other radio is transmitting a designated low-frequency tone or a digital code along with the voice transmission. The low-frequency tones system is actually called “Continuous Tone-Coded Squelch System” or “CTCSS”. The digital code system is called “Digital Code Squelch”, or “DCS. There are 50 tone frequencies that can work with CTCSS (only about 38 of these codes are available on most radios), and 512 DCS codes available (only about 83 of these codes are available on most radios).
The challenge with these “Privacy Codes” is that the manufacturers have not settled on standard identifiers for them. CTCSS Tones are by tone frequency, starting at 67 Hz on up to 254.1 Hz (there are a total of 50 discreet tones in this range). DCS codes are typically represented as an octal number ranging from 023 up to 754 (again, there are a total of 512 discreet codes available. However, the manufacturers typically represent those codes with a number, letter, or number/letter combination. For example, on a Cherokee 465 radio, CTCSS tone 173.8 is represented by “30”, while Radio Shack represents this same tone as “32”. On DCS, Midland identifies code 054 as “9”, while the Retrvis RB15 identifies this same code as “11”. So, it’s not that these radios can’t communicate with each other, it’s that the users need to know how to cross-reference the codes so everyone in the communications group is on the same sheet of music. We provide tables for MURS, FRS, and GMRS radio manufacturers to help you sort this out. Your radio manual should also list the specific tones or codes represented by their specific designator system as well.
If you note any errors in these FUPs, or have recommendations for additions or changes, please send an email to firstname.lastname@example.org.
Amateur Radio 6-Meter FUP
Amateur Radio 2-Meter FUP
Amateur Radio 1.25 Meter FUP
Amateur Radio 70 cm FUP
Amateur Radio 33 cm FUP
FRS FUP — FRS CTCSS and DCS Codes