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SteveOFD

Frequencies

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Check out these frequencies:

453.2000, 458.2000, 460.1125, 465.1125, 462.9500, 467.9500

453.2625, 458.2625

453.0250, 458.0250

154.3400, 453.6750, 458.6750

153.9800

153.8300, 153.8900

153.8300, 154.1600

478.0500, 481.0500

156.0000, 453.1875, 458.1875

460.0125, 465.0125, 460.2375, 465.2375, 460.5875, 465.5875

453.2750, 458.2750, 453.6500, 458.6500

453.4125, 458.4125, 460.0250, 465.0250, 460.2750, 465.2750

472.0500, 475.0500

153.8300, 154.1450, 153.7700

460.1000, 465.1000, 460.4625, 465.4625, 465.5875, 465.6125, 465.6375

460.5875, 465.5875, 460.6125, 460.6375

453.2250, 458.2250, 453.8750, 458.8750

453.7875, 458.7875

453.3500, 458.3500, 453.9750, 458.9750

460.3500, 465.3500

154.2050, 154.3100

154.1000

155.7750

156.2250

472.2500, 475.2500

453.5000, 458.5000, 453.5500

453.3250, 458.3250, 453.5625, 458.5625

484.7125, 487.7125, 453.6625, 458.6625, 465.5500, 465.6000

These are frequencies that individual Westchester County FD's are licensed for according to FCC.gov Database Search. The above list contains 87 individual frequencies. Everyone knows that there is a shortage of frequencies available for Public Safety use. This shortage is the main reason why starting next year everyone will transition to digital TV. This transition will make available frequencies in the 700MHz frequency band that TV broadcasters will be leaving in this switch over. These 700MHz frequencies will be available for Public Safety use.

I did a calculation and found that within each 1MHz of spectrum (i.e. 470.000-470.9875) there are 80 available frequencies (channels). This is calculated on the current standard of 12.5kHz spacing (0.0125) between channels. Of these 80 channels not all can be be used in each area. Adjacent channels to other users (co-channel use) is not allowed due to interference possibilities. This means if you are licensed for 470.5000, the frequencies 470.4875 & 470.5125 are not available for use within a geographical radius around your location.

So, with the individual licensing of these 87 frequencies, these individual FD's are not just using the spectrum of these 87 frequencies, but also preventing the use of the 174 adjacent frequencies. With 80 channels per 1MHz, this means that individual licensing by Westchester Co. FD's is actually affecting the usage of over 2MHz of spectrum. This affects not only users in Westchester, but also adjacent users in Putnam, Rockland, NYC, NJ & CT. If we were to include individual licenses of all other Municipal users (PD, EMS, DPW, etc.) there is a lot of spectrum that is being used just because everyone wants their own channel.

I am not saying that we all need to go to a trunked system (which does increase spectrum efficiency), what I am pointing out is that we all should review our individual communications needs and look at the big picture of why there is a shortage of frequencies.

*Note - no names are listed for the above list because this is an overall problem, not blaming any individual agency.

Edited by SteveOFD

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Check out these frequencies:......

1) I noticed a number of repeats (so it maybe less than 87)

2) NYC has more frequencies on reserve (i.e. not used, but being held incase its ever needed) in additiona to all the ones they do use, then we will ever have. Multiply that figure.

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2) NYC has more frequencies on reserve (i.e. not used, but being held incase its ever needed) in additiona to all the ones they do use, then we will ever have. Multiply that figure.

The points I was trying to make is that when a frequency is assigned, the adjacent two frequencies become unavailable, and that the assignment of that frequency just does not affect us in Westchester, but also adjacent Counties and States that these frequencies become unavailable for use also.

So, yes the reserve of frequencies by NYC affects us by not allowing us that freq and the adjacent channels, and this is also the same with agencies in adjacent Counties and States with reserve and existing frequencies.

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