225-400 MHz Spectrum Holes

[blantonl]

Larry Van Horn posted this excellent post on his blog today. Anyone want to give these a shot and see what they find?

http://mt-milcom.blogspot.com/2011/08/uhf-225-380-mhz-milcom-spectrum-holes.html

I have written a lot over the years on this blog and other media about what I call spectrum holes in the 225-400 MHz range. In brief a spectrum hole is a legit frequency for assignment based on current channel spacing and the DoD bandplan, but no activity/current assignment has ever been heard/found for a frequency. That is a spectrum hole. If you are interested in exploring the world of 225-400 MHz spectrum holes, I have now created this page for those who want to monitor a challenge. And if you hear something or know something about one of these freqs, I would appreciate an email at the address in the masthead.

And if you don't have room for the complete list, here is the big Milcom challenge: These freqs are the biggest Milair unknowns on the planet. if you hear something on these I would like to really hear from you. Try programming these mystery freqs: 233.600 252.300 252.600 277.300 293.900 298.200 336.700 371.400 MHz.

226.2500 234.1750 236.9250 239.0750 244.6750 244.9250 245.0750 248.5250 248.7750 249.6750 249.7250 250.3750 250.4750 250.5750 250.8750 251.6250 251.6750 252.3750 252.4500 252.8750 253.1750 253.4250 254.6250 254.8750 255.0250 255.3250 255.4750 255.5250 255.6750 256.4250 256.9750 258.0250 258.4750 258.5250 259.0750 259.2750 259.6250 259.7750 264.4750 265.3750 265.4750 265.6250 265.8750 266.8250 266.9250 267.0250 267.1250 267.2250 267.3250 267.9500 267.9750 268.3250 269.8750 269.9250 270.0750 270.4250 270.4750 270.9250 271.0500 271.1500 271.3750 271.7750 271.9250 273.8750 274.0250 274.2250 274.2750 274.9250 275.0750 275.6250 275.7250 276.1750 276.5750 276.7250 276.7750 276.8750 277.1750 277.2750 277.4750 277.5750 277.6750 277.7750 277.8750 277.9500 277.9750 278.0750 278.5250 279.3250 281.2250 284.3250 290.8250 292.7500 292.8250 293.0750 293.5750 297.9250 299.4250 302.3250 305.7750 305.9750 306.2750 306.4750 306.5250 306.6250 306.6750 307.7750 307.8250 307.9250 308.2250 308.3750 308.6750 309.1750 309.2250 310.0250 310.1750 310.2750 310.5750 310.7750 310.8750 311.0750 311.8750 313.9500 313.9750 316.4250 316.4750 318.4250 318.6250 318.7750 319.0750 324.2250 324.5750 324.7750 326.3750 326.4250 326.8750 328.3250 328.4750 339.8750 341.8250 342.6250 346.4750 346.5750 348.0750 349.8750 350.1750 352.1250 355.4250 358.7750 360.1750 361.5250 361.6250 363.5750 365.6750 365.9750 367.5750 368.9250 369.3750 373.6750 375.9750 377.4750 377.7500 377.7750 378.0750

Good luck!

 

[R1VINCE]

I'll take a crack at it!
Will post back with audio when able.

 

[brandon]

I have logged 233.600 here in SoCal. Need to id but sounded like pilot with O2 mask.

 

[MtnBiker2005]

The main Spectrum Holes page on MT MilCom. [The page tab on the top of the blog]
http://mt-milcom.blogspot.com/p/uhf-225-380-mhz-milcom-spectrum-holes.html

 

[gvranchosbill]

Ive heard traffic on:
298.200 Air/Air Fallon NAS/NSAWC

This is on list but i havent heard anything on it yet.
336.700 CVW-1 Air/Air Fallon NAS/NSAWC

The larger freq list will take more time to match with my list.

 

[nd5y]

336.700

I just noticed this today. 336.700 is used at Sheppard AFB, TX.
It's the T-38 Runway Supervisor Unit (callsign "Tinder").
I had seen another frequency 338.900 listed for that but never heard anything on it. They may have changed to 336.700 years ago.

 

[Saint]

I'll listen in

I put all the frequencies into my scanner and will listen in and post anything I find.
Steve
Fort Erie Ont.

 

[krokus]

Tagging in, so I can add some of these, once I get home.

Sent via Tapatalk

 

[NDRADIONUT]

233.6000 NORAD HUNTRESS / AWACS - Duluth ANG

 

[jbsarandolphmonitor]

I will try to see if any of these frequencies are used at Randolph AFB.

Thanks
Don

 

[K5MPH]

Good ol Larry an native of TEXAS love his books,over the past years i have heard spanish traffic on 250.3750 but i live very close to the Mexcan border....

 

[Airboss]

Latest UHF Milair Spectrum Hole List

Greetings from North Carolina.

Since Lindsey posted the spectrum hole list from the Milcom MP blog almost five years ago, more than a few from that original list have been identified and are no longer on the list. Now that list is down to 116 freqs left. Here are the last holdouts that have not had any activity heard on them.

226.250 234.175 236.925 239.075 244.675 244.925 245.075 248.525 248.775 249.675 249.725 250.375 250.475 250.575 250.875 251.625 251.675 252.375 252.450 252.875 253.175 253.425 254.625 254.875 255.025 255.325 255.475 255.525 255.675 256.425 256.975 258.025 258.475 258.525 259.075 259.625 259.775 264.475 265.375 265.475 265.625 265.875 266.825 266.925 267.025 267.125 267.225 267.325 267.950 267.975 268.325 269.875 269.925 270.075 270.425 270.475 270.925 271.050 271.775 271.925 274.225 274.275 274.925 275.075 275.625 275.725 276.175 276.725 276.775 276.875 277.475 277.575 277.675 277.875 277.975 278.525 279.325 293.075 293.575 297.925 305.975 306.275 306.475 306.525 306.675 307.825 307.925 308.375 308.675 310.025 310.175 310.275 310.775 310.875 311.075 311.875 316.475 318.425 318.625 318.775 319.075 324.225 326.375 326.425 342.625 346.475 346.575 348.075 349.875 350.175 358.775 360.175 361.525 365.675 365.975 367.575 368.925 369.375 375.975 377.475 377.750 378.075

The current list is also posted to our Milcom blog page devoted to the UHF spectrum hole freqs at
Milcom Monitoring Post: UHF 225-380 MHz Milcom Spectrum Holes

If you hear anything on any of the frequencies listed above, we would like to hear from you. You can reach me here at RadioRef or via email teakpub@frontier.com.

73 and good hunting,

Larry

Larry Van Horn, ATC (AW) USN (Ret)
President Teak Publishing - Brasstown, NC USA
Twitter: @MilcomMP, Mode-S Monitor
Milcom Monitoring Post http://mt-milcom.blogspot.com/