This page was
UPDATED June 01, 2003
by Dr.Ace - WH2T

2 Meter Simplex Frequencies


Two Meter Band Simplex Frequencies

For many years the Repeater Directory has included a 2 Meter Band Plan and list of Simplex Frequencies standardized on 15-Khz splinter channels.

Section 97.101(a) of the Amateur Radio Service rules refers to "good engineering and good amateur practice"--considered to refer to maintaining the highest standards of engineering and on-the-air comportment.

According to FCC Special Counsel Riley Hollingsworth, good amateur practice means: Among other things "respecting band plans..."

Using these standardized 15-Khz splinter channels minimizes interference to other amateur radio operators.
In the interest of promoting good Amateur Practice,
Here is a list of those Frequencies.

146.400***
146.415
146.43
146.445
146.46
146.475
146.49
146.505
146.52 National Simplex Calling Frequency
146.535
146.55
146.565
146.58
147.42
147.435
147.45
147.465
147.48
147.495
147.51
147.525
147.54
147.555
147.57
 
*** The frequency 146.400 MHz is used in some areas as a repeater input.
 
 


 
*** The FCC's position on band plans ***

FCC Special Counsel for Amateur Radio Enforcement Riley Hollingsworth used the occasion of an enforcement letter to commend the value of band plans.

"Although band plans are not mandatory, they exist to enhance the required cooperation and sharing of frequencies in the Amateur Service," Hollingsworth said in an enforcement inquiry to a Connecticut ham.

The FCC wrote Advanced licensee Alan J. Koepke, K1JCL, on October 11, 2000, citing complaints received by the Commission alleging that Koepke's 2 meter operations were causing interference to other amateurs.

"Band plans minimize the necessity for Commission intervention in Amateur operations and the use of Commission resources to resolve amateur interference problems," Hollingsworth wrote in expressing the FCC's position on band plans.

"When such plans are not followed and harmful interference results, we expect very substantial justification to be provided, and we expect that justification to be consistent with Section 97.101."

Hollingsworth said he included the statement to reiterate where the FCC stands on the question of band plans.
 


 

Amateur FM History

If you are a newcomer to VHF-FM, and particularly if you have just arrived from one of Amateur Radio's other bands or modes, you are probably somewhat curious about the high degree of organization that has come about on our VHF bands. While space doesn't permit a complete history of Amateur FM, here is a brief explanation of the Amateur FM structure and how it came to be.

On our FM bands, Amateurs have voluntarily designated certain frequencies as "channels". These channels have not been assigned numbers, like television or CB. Rather they are referred to by their actual frequency such as "one forty seven dot two one" (147.21) or just "two-one". On the 220 MHz band these channels are 20 kHz apart. FM channels on the 440 MHz band are 25 kHz apart, with some new repeaters using 12.5 kHz spacing.

Why have channels at all when we can legally operate on any frequency in the band? The reason is that FM operation was originally crystal controlled, both transmit and receive. While a fully tunable VFO is considered an advantage on the HF bands, on VHF it was difficult and expensive to duplicate a crystals high accuracy and stability in the early days of VHF FM. Also, and perhaps more important, the first equipment in general use on Amateur FM was converted commercial surplus equipment (police or taxi style radios), all of which was crystal controlled to assure reliable, immediate communications.

In the early days with everyone using crystals for transmitting and receiving, specific frequencies (or channels) had to be set aside so FM'ers could talk to each other. 146.94 MHz became a popular frequency nationwide on two meters. A certain spacing was needed between channels to avoid adjacent-channel interference, so at first 60 kHz was used ( a practice borrowed from the nearby commercial band). Later, as narrow band FM became more predominant, spacing was reduced to 30 kHz and again later to 15 kHz.

The channel concept was found to have many advantages. Monitoring was a prime one. Many FM'ers began listening on the popular channels with squelched receivers, and a brief call was all that was needed to establish contact. No more CQ calls or tedious "tuning the band" is necessary on today's busy FM channels.

Besides being divided into channels, the FM bands are further divided into sub-bands, with one set of sub bands dedicated to simplex operation and the other dedicated to repeater use. The repeater sub-bands are further divided into repeater "pairs" for repeater inputs and outputs. The scheme that determines how the frequencies are to be used is called the "Band Plan".

The Band Plan has been endorsed and adopted by the ARRL, and the FCC continues their very strong support. It resulted from the need for orderly growth on two meter FM. Band Plans now exist for 10 meters, 6 meters, 2 meters, 220 MHz, 440 MHz, and above.
 

Special Note

Because of the geographical isolation of the main population centers of Utah they adopted 20 KHz channel spacing on 2 meters. Operation has occurred in a "vacuum" and usually has had little or no impact on neighboring regions.

Two Meter Band FM Channelized Frequencies
Ace's 2 Meter FM Frequencies Info

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