All posts by Nick
Below are all of Nick's postings, with the most recent are at the bottom of the page.
Chris SE,
Thanks. Whatever the reason, the new arrangement is far better than when we had muxes on c58 and c60.
Do you know about aerials? I am staggered how good the log periodic is. Perhaps they have been improved over the years. Does each element receive the signal, thus adding to performance? For example, the longest and shortest element also increase the signal for c39, albeit they are the wrong length?
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Chris SE,
Thank you. I will study these. Each element is tuned to its frequency but doubtless all the others get a lesser signal too, adding to overall performance, and doubtless the smaller space between the smaller elements gives some of the advantages of a yagi.
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Chris SE.
I have made what I think is an interesting discovery today testing several aerials at only 6ft from the ground. They all have good reception but they ALL are very poor with regard to signal quality, 33%, on channel 37, right in the middle of the range of channels used by Sudbury. This is presumably why 37 is the first to go on my rooftop aerial. if 47 were poor, or 29 were poor, I could understand it was an aerial problem, but this is a mystery. Any ideas please?
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Chris SE, thanks. I follow your reasoning here. This must be some form of interference, and I suspect from your notes, that it must be that Holland has a troublesome transmitter on this channel.
It is almost impossible to locate my test aerials elsewhere, but I have made further discoveries. Signal quality on 37 improves after dark.
Some of my aerials, during the day, show the quality jumps up from 30 to 90, but then within a second jumps back down..
I have tested several aerials, and the log is second best. The only one that defeats this problem during the day is home made and produces a steady 70 plus quality. Basically it is the old fashioned 18 element group B, but with two parallel groups of 16 directors and a circular dipole about 8 ins diameter. which markedly improves the bandwidth. The directivity may be keeping out the intruder.
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Thursday 18 May 2023 6:15PM
Chris SE
Thank you for your explanation.
Did you see my query about why we did not have the current reasonably close group of channels in the first place?
If it can be done now, why could it not be done then?