In reply to MM0FMF:
In reply to a few posters, I am sure a spark transmitter couldn’t be worse than living next door to someone with a PLT/PLA device, or numerous other things that cause horrendous QRM for users of shortwave. The only difference is that a spark transmitter is (Very) wideband.
Back to the original subject, I have looked at the proposal from the MOD & like many others am concerned by the 5m max antenna height requirement.
I have always given the height of my 80m wire loop as 6m AGL, but today for an unrelated reason I decided to actually measure it. While what could be described as it’s feedpoint in the attic above my head, is indeed around 6m AGL, the antenna wire leaves the building at gutter level which is only 5.4m / 6m AGL depending on which side of the house I measure. From this, it appears that the majority of my antenna is only about 4.5m AGL, which is much lower than I would have thought.
Overall, still over the 5m height limit though.
The 200 Watts EIRP limit would not seriously affect most UK amateurs as most of us only run 100 Watts maximum into nothing more than a dipole. As the gain of a dipole (according to Wikipedia as my memory is a bit slow)is given as 2.15dBi,you would still be fine running your 100 Watt radio into a simple dipole.
I am sure the MOD do not want the band to be used for DX working, which I tend to agree with, as the band is far too useful to become another 40m, which at present exhibits similar NVIS properties. However, as some respondents to the
Litmus test have already said, the 5m height limit would automatically prevent use by stations with antennas located on tall buildings, or even over the ridge of a normal house. This would be a problem when assisting the relevant services during any emergency / disaster situation.
The offer of additional spectrum is to be welcomed, & the widening of FE to allow AM use suggests that the MOD themselves are becoming more flexible with other services using their portions of the MF/HF spectrum, but of course this does mean that there is more pressure on the UHF/SHF amateur allocations.
I have yet to respond to the Litmus test myself, but I will certainly be putting my views forward as I feel this is a very important part of the spectrum that we as amateurs can, and are, making very good use of.
Any changes should take into account that most of us live in houses, with neighbours, & limited space for multiple antennas. In some cases not even room for one!
The above views are my own, & do not represent SOTA in any way.
Apologies for any errors,