KZOB: 120.770 vs 120.775

[eorange]

In just about every online reference, the frequency for the Chardon RCAG - Youngstown Low Sector is listed as 120.775. But Cleveland ARTCC Website shows this frequency as 120.770. Do a Google search on "cleveland artcc 120.770" to see files from the Cleveland Center site defining the frequency as 120.770. In fact these are the only 2 search results. Repeating that same search with 120.775 lists tons of references.

I would have never found this otherwise, but when I listen to Aerial Refueling the pilots clearly declare the Cleveland Center handoff frequency as 120.770.

I've always known it as 120.775. When I tune in with any radio, 120.770 sounds off frequency and 120.775 sounds right on.

I wonder why the discrepancy? It's hard to believe the Cleveland Center website and ARW operations isn't consistent with every other source of info.

 

[RaleighGuy]

In just about every online reference, the frequency for the Chardon RCAG - Youngstown Low Sector is listed as 120.775. But Cleveland ARTCC Website shows this frequency as 120.770. Do a Google search on "cleveland artcc 120.770" to see files from the Cleveland Center site defining the frequency as 120.770. In fact these are the only 2 search results. Repeating that same search with 120.775 lists tons of references.

I would have never found this otherwise, but when I listen to Aerial Refueling the pilots clearly declare the Cleveland Center handoff frequency as 120.770.

I've always known it as 120.775. When I tune in with any radio, 120.770 sounds off frequency and 120.775 sounds right on.

I wonder why the discrepancy? It's hard to believe the Cleveland Center website and ARW operations isn't consistent with every other source of info.

Airline freqs are spacing is 25, (00 25 50 75) many times when the freq is given the last digit either 5 or 0 is not said/listed because those using the radios know this. I often hear something like "Switch to 129.17" meaning 129.175. A couple of examples out of the NC DOT Airport guide, issued by the state....

 

[AI7PM]

I will confirm N1AGW's answer. The third digit is not pronounced in ATC phraseology. Unfortunately, many who create, publish, or otherwise distribute airband frequency information do not understand this and convey inaccurate data.

 

[dlwtrunked]

In just about every online reference, the frequency for the Chardon RCAG - Youngstown Low Sector is listed as 120.775. But Cleveland ARTCC Website shows this frequency as 120.770. Do a Google search on "cleveland artcc 120.770" to see files from the Cleveland Center site defining the frequency as 120.770. In fact these are the only 2 search results. Repeating that same search with 120.775 lists tons of references.

I would have never found this otherwise, but when I listen to Aerial Refueling the pilots clearly declare the Cleveland Center handoff frequency as 120.770.

I've always known it as 120.775. When I tune in with any radio, 120.770 sounds off frequency and 120.775 sounds right on.

I wonder why the discrepancy? It's hard to believe the Cleveland Center website and ARW operations isn't consistent with every other source of info.

Two points:
1. An official FAA document, if you want one, is at the website below--see page 408.

https://aeronav.faa.gov/Upload_313-d/supplements/CS_EC_20201231.pdf

2. when looking at the website you are using, note:
" VATUSA is a division of the VATSIM Americas region comprising of almost all airspace operated by the real world Federal Aviation Administration. The airspace comprises of 20 Air Route Traffic Control Centers (contiguous US and Anchorage), 1 Control Facility (Pacific Control Facility) and 1 CERAP (Guam CERAP, under management of PCF). All information contained within this website is designated for use with the VATSIM network and for flight simulation purposes. Information is not intended nor should be used for real world navigation and its use for real world navigation could be in violation of federal laws. This website is not affiliated with the Federal Aviation Administration or any other governing body. "
So I would not consider the site you referenced as "official".

 

[alcahuete]

And so you know, that is NOT Cleveland Center's website. That is Cleveland Center for VATSIM, which is a virtual pilot/ATC environment. The frequency is 120.77(5) with the 5 not spoken on the radio.

 

[AirScan]

Has has been established above, the actual frequency is 120.775. However about your tanker comment.

when I listen to Aerial Refueling the pilots clearly declare the Cleveland Center handoff frequency as 120.770.

Are the tanker pilots actually saying it with the ZERO at the end ? "Point Seven Seven Zero" ? Was this just a one time thing, slip of the tongue, or are you hearing this as a standard when refueling ?

As most tankers operate worldwide missions they would be equipped with radios that use 12.5 kHz spacing so they can fly in Europe. These radios display the 3rd digit on the selector display, and in areas where they are required the 3rd digit is used and pronounced in standard ATC phraseology.

I'm going take a wild guess and say that the controller used the standard North American terminology and told them "120.77" (no zero at the end) and then after the pilot selected "77" they just read back what they saw on the radio's frequency display "120.770" (120.775 would be the actual frequency automatically tuned by the radio). Maybe they just came back from a European mission and were still used to using and saying the 3rd digit ? Like I say just a wild guess, more info required.

 

[eorange]

Interesting. So the correct freq representation is 120.77, but the 25 kHz step in the radio will take them to 120.775. Makes sense.

Regarding the web site: I thought it looked a little, well, strange for an official ARTCC site. The term VATSIM sounds vaguely familiar, but I wouldn't have known enough to know what I was looking at.

Regarding the tanker: the pilot had to repeat the frequency about 3 times. It sounded a little broken up to me, but I couldn't tell if the receiver just wasn't copying or if there was some other issue. But on the 3rd time, the pilot said one-two-zero-dot-seven-seven-ZERO, with extra emphasis at the end. Maybe it was just because of bad copy or, well, frustration.

 

[RaleighGuy]

Regarding the web site: I thought it looked a little, well, strange for an official ARTCC site. The term VATSIM sounds vaguely familiar, but I wouldn't have known enough to know what I was looking at.

Gee I hope, after 17 years and 2500 posts on RR, your "secret agent man" assignments don't have you spying on websites or airlines Hahaha

Said in fun, not as a negative comment.

 

[eorange]

BTW, thanks all, this is great info.

 

[AI7PM]

...As most tankers operate worldwide missions they would be equipped with radios that use 12.5 kHz spacing so they can fly in Europe. .....

Radios capable of 8.33khz spacing are required in European airspace now. Why the US hasn't adopted this, at least in the upper flight levels is odd.

 

[xms3200]

VHF frequency congestion is not bad here in the U.S as compared to the frequency congestion in Europe. U.S is such a big country, spacing is not yet that much of a problem.

 

[AirScan]

Radios capable of 8.33khz spacing are required in European airspace now.

Typo on my part, I meant 8.33 not 12.5. D'oh.

 

[spanky15805]

Radios capable of 8.33khz spacing are required in European airspace now. Why the US hasn't adopted this, at least in the upper flight levels is odd.

8.33 is coming. ICAO has a 2020 update to their manual. I still haven't firgured out how the "Climax" offset carrier is going to work.
Heres a chart of how the 25khz is going to be setup.
8.33kHz VCS User Handbook Part I –Operational Considerations
Page 30 released edition: 1.1
5.2 Communication procedures
The radiotelephony communication procedures are established in accordance with ICAO
Annex 10, Volume II, Chapter 5. It is essential, in the context of 8.33kHz VCS
deployment that all Flight crews (including GA pilots), ATS personnel and other ground
personnel are thoroughly familiar with the appropriate radiotelephony procedures.
The introduction of 8.33 kHz channel spacing has resulted in a 6-digit channel
numbering scheme, where the 8.33 kHz channel designators differ from the actual
frequency; e.g. 8.33 kHz channel 132.035 tunes the frequency 132.0333 MHz.
The ICAO Annex 10 VII prescribes the procedure for a 6-digit pronunciation of both 8.33
kHz and 25 kHz channels in VHF radio telephony communications, except in the case of
both the fifth and sixth digits being zeros, in which case only the first four digits should be
used. The following examples illustrate the application of this procedure:
Channel (8.33 kHz/25 kHz) Transmitted as
118.000 (25 kHz) ONE ONE EIGHT DECIMAL ZERO
118.005 (8.33 kHz) ONE ONE EIGHT DECIMAL ZERO ZERO FIVE
118.010 (8.33 kHz) ONE ONE EIGHT DECIMAL ZERO ONE ZERO
118.025 (25 kHz) ONE ONE EIGHT DECIMAL ZERO TWO FIVE
118.100 (25 kHz) ONE ONE EIGHT DECIMAL ONE
Note: the initial proposed use of the term “CHANNEL” in conjunction with 8.33 kHz
channels has been discontinued.
However, caution must be exercised with respect to the indication of transmitting
channels in VHF radiotelephony communications when all six digits of the numerical
designator are used in airspace where communication channels are separated by 25
kHz, because on aircraft installations with a channel separation capability of 25 kHz or
more, it is only possible to select the first five digits of the numerical designator on the
radio management panel. Additional training may be required for pilots to cover for the
use of the radio equipment in such situations.
ATS should maintain in addition to the VHF 2-way radio communications, a continuous
watch on the appropriate VHF emergency channels and if available UHF, in order to
ensure that air traffic controllers are informed about distress transmissions in the area of
responsibility