Peter wrote:
A 25k radio will be modulating the same audio onto the carrier as an 8.33 radio i.e. about 4kHz wide, max, (taking both sidebands),
But a carrier of a 25 kHz radio may be sufficiently off to cause interference with adjacent 8.33 channels.
I know you’ve said that the carrier frequency accuracy of all 25 kHz radios are as good as that of a 8.33 kHz set. I believe you, but the problem is that the standards permit much lower accuracy.
Isn’t that really a debate on how to overtly or covertly force people to throw out these (and similar vintage stuff):
If that really was the objective (and IMHO it probably is a part of the 8.33 initiative to force people to update equipment, because so many people do fly with barely working radios) then it would have been better to issue an AD on all the old junk. What we have instead is people being forced to throw out perfectly good modern stuff e.g. KX155A. American pilots are laughing at Europeans chucking out perfectly good radios worth $2k or so over there, and a lot of them are making nice money selling us KX165A-0201 (8.33) radios for about $4k for a refurb one which cannot be installed anyway on an EASA-reg unless you get an EASA-1 or a dual release 8130-3…
Mand what everyone who even remotely worries about this keeps forgetting that – excuse the shouting – THAT WHERE 25 KHZ FREQUENCIES WILL REMAIN THE CORRESPONDING 8.33 KHZ FREQUENCIES ARE UNALLOCATED SO THERE IS NOTHING TO BE INTERFERED WITH.
Sure, but the other part of this is that even if allocated 130.005 you can just set 130.000 on your 25k radio and nobody will know.
And the two adjacent 8.33 channels will not see any interference (unless your radio is well off calibration).
Cobalt +1…..and WE don’t choose which freqs to use, if you are given a 25khz freq to use, it makes no difference whether you use you 25khz radio, or your new shiny 8.33… as it is in fact an 8.33 + 25 radio !!
Cobalt wrote:
Mand what everyone who even remotely worries about this keeps forgetting that – excuse the shouting – THAT WHERE 25 KHZ FREQUENCIES WILL REMAIN THE CORRESPONDING 8.33 KHZ FREQUENCIES ARE UNALLOCATED SO THERE IS NOTHING TO BE INTERFERED WITH.
I’m not “forgetting” that at all. The thing is that the 25 kHz channels will go away. They must in order to free bandwidth for new channels.
Airborne_Again wrote:
I’m not “forgetting” that at all. The thing is that the 25 kHz channels will go away. They must in order to free bandwidth for new channels.
Will they? Only in the geographic areas that require more freqs. Several countries are delaying/not implementing 8.33, so it’s not going to happen that quickly.
If you look at a chart of channel saturation, the problem exists mainly in Germany, France, Benelux and England. Outside that band there is not really a problem, so Ireland, Scandinavia, Iberia, Italy, Eastern Europe and the Balkans could afford to wait a long time, possibly forever, whereas those core countries need to have completed the process quite soon.
PeteD wrote:
Several countries are delaying/not implementing 8.33, so it’s not going to happen that quickly.
Really? I thought even a partial national exemption from Eurocontrol was difficult to get. Do you have a list of those countries?
