Date
1 - 5 of 5
Order to vacate 420 to 430 MHz
|
KC7QY
FYI - From a message sent out by Bill W5YEJ on the repeater owners group. "Per request of the U.S. Army the FCC had ordered that we vacate the 420 to 430 MHz segment of the 70cm band to make way for a new project on WSMR. Area included: All Amateur transmitters within LOS of WSMR and any other location that may cause interference on the Range. Sandia Peak, Manzano Mtns, Capilla, Organ Pass, Benson Ridge, Long Ridge, Buck Mountain & El Paso are all within the area of concern as well as the Tularosa Basin. This list is not all inclusive and may need to be expanded if interference is found at sources outside the LOS area. Note that frequency coordination is primarily used to protect receivers from unwanted signals. In this case the receiver(s) location is not specified and so is a bit difficult to determine which, if any, other locations may need to be included. When: FCC has said we must vacate the band segment or turn off any transmitters within the 420-430 range by May 31, 2021. This doesn't give us a lot of time to rearrange channels. What do you need to do? If you're operating transmitters (links or repeaters) with the range of 420 to 430 please contact me ASAP so I can verify the NMFCC database is up to date. I was officially notified of this order on March 16th and have been trying to come up with a plan to move transmitters. If you have suggestions please let me know. FYI, here is the band plan from the ARRL: 70 Centimeters (420-450 MHz) 420.00-426.00 ATV repeater or simplex with 421.25 MHz video carrier control links and experimental 426.00-432.00 ATV simplex with 427.250-MHz video carrier frequency 432.00-432.07 EME (Earth-Moon-Earth) 432.07-432.10 Weak-signal CW 432.10 70-cm calling frequency 432.10-432.30 Mixed-mode and weak-signal work 432.30-432.40 Propagation beacons 432.40-433.00 Mixed-mode and weak-signal work 433.00-435.00 Auxiliary/repeater links 435.00-438.00 Satellite only (internationally) 438.00-444.00 ATV repeater input with 439.250-MHz video carrier frequency and repeater links 442.00-445.00 Repeater inputs and outputs (local option) 445.00-447.00 Shared by auxiliary and control links, repeaters and simplex (local option) 446.00 National simplex frequency 447.00-450.00 Repeater inputs and outputs (local option) I suggest we use the 433.00-435.00 and 438.00-440.00 segments to move transmitters currently in the 420-430 segment. Paul Choc advises some of his equipment may not go high enough to operate in the 438 MHz range and has suggested we might use 430.00-430.975 MHz and 434.00-434.975 MHz (4 MHz split) for some links. I am soliciting your comments on both of these suggestions whether or not you are affected. I don't want to make unilateral changes that will impact Amateur operation on the 70cm band for so long as we are operating there (and I wont be around that long anyway). I would prefer your comments in writing so I have a record but you are also welcome to call me any time. Bill, W5YEJ" Jim KC7QY |
|
|
|
Daniel Fay
FYI -- I'm currently doing some mesh networking experiments with the LoRa waveform on 420-430MHz. This order shouldn't affect me because:
If you think this order does apply to what I'm doing, let me know, and I'll change frequencies. The LoRa radios can operate anywhere in the 70cm band. Also, is this change permanent? I was considering eventually emplacing a few network nodes across the ABQ metro area to evaluate coverage. Thanks, Dan KG5VBY |
|
|
|
KC7QY
Dan, I afraid what is in the message is all that I know about it. The take-away for me is that if you deploy a system in that range then you are at risk of having to reconfigure your system if you do end up interfering. Jim KC7QY
On Friday, March 19, 2021, 01:50:03 PM MDT, Daniel Fay <daniel.fay@...> wrote:
FYI -- I'm currently doing some mesh networking experiments with the LoRa waveform on 420-430MHz. This order shouldn't affect me because:
If you think this order does apply to what I'm doing, let me know, and I'll change frequencies. The LoRa radios can operate anywhere in the 70cm band. Also, is this change permanent? I was considering eventually emplacing a few network nodes across the ABQ metro area to evaluate coverage. Thanks, Dan KG5VBY |
|
|
|
Brian Mileshosky
Jim and everyone — Please disregard (most) of the original note below. While WSMR is indeed bringing about a capability that is sensitive around that part of the 70cm band, the FCC has *not* issued an order, in any shape or form, for anybody anywhere to vacate that part of the band by anytime. ARRL is working in real-time with FCC, WSMR and DOD’s spectral management office to understand the issue and jointly explore avenues to mitigate interference with minimal impact to the amateur radio community. They are working to limit potential impacts only a few links on specific frequencies in specific areas adjacent to WSMR...not all occupants of an entire sub-band across a broad geographic area. For now, it’s best to treat this as “for awareness only” and await official guidance from ARRL based on what they, WSMR, DOD, and FCC determine is and message the least impactful path forward. The original messaging below has certain inaccuracies that shouldn’t be propagated further to prevent any sort of panic. Bill W5YEJ has since issued a correction stating that no such FCC order exists. 73, Brian N5ZGT On Mar 19, 2021, at 13:29, KC7QY <kc7qy@...> wrote:
|
|
|
|
KC7QY
Brian, Thanks for the clarification. Since I can see WSMR from my shack window (at least the mountains on the west side anyway) I probably am a little more sensitive to what happens there than most. This certainly is a reminder that we are a secondary user on 70cm anyway. Jim KC7QY
On Friday, March 19, 2021, 08:08:11 PM UTC, Brian Mileshosky <bpmiles@...> wrote:
Jim and everyone — Please disregard (most) of the original note below. While WSMR is indeed bringing about a capability that is sensitive around that part of the 70cm band, the FCC has *not* issued an order, in any shape or form, for anybody anywhere to vacate that part of the band by anytime. ARRL is working in real-time with FCC, WSMR and DOD’s spectral management office to understand the issue and jointly explore avenues to mitigate interference with minimal impact to the amateur radio community. They are working to limit potential impacts only a few links on specific frequencies in specific areas adjacent to WSMR...not all occupants of an entire sub-band across a broad geographic area. For now, it’s best to treat this as “for awareness only” and await official guidance from ARRL based on what they, WSMR, DOD, and FCC determine is and message the least impactful path forward. The original messaging below has certain inaccuracies that shouldn’t be propagated further to prevent any sort of panic. Bill W5YEJ has since issued a correction stating that no such FCC order exists. 73, Brian N5ZGT On Mar 19, 2021, at 13:29, KC7QY <kc7qy@...> wrote:
|
|
|