Hi to all,
I have recentky installed a scan king on my house roof top.
It is connected to my Baofeng UVR5H via a 20 meter lengh
Of RG58. The problem is that the reception is no better than
the standard walkie talkie issued antenna.
There are no breakages in cable and all connected via a smaller
adapter into the hand set.
Thanks in advance.
On UHF bands, over half the received signal is lost in the cable. A typical wide band antenna is probably nearly as good as the antenna on your radio - so all it’s advantages come from it’s height, not performance. Net result is often as you have discovered, the performance gain from the height is eaten up by cable loss. thin cable is less bad at VHF, but rapidly gets unworkable as frequency increases. Thick cable is lower loss in general. RG58 is for UHF, OK on your car, but not much cop for a roof mounted antenna.
I would think an RF amplifier would be needed AT the antenna to provide sufficient “gain” for the signal to overcome the coax cable loss and even enhance reception.
That solution is standard when installing a tv antenna to negate signal loss in the coax.
Best wishesđź‘Ť Tom WRQE346
I think we are a long way from peak performance. Masthead preamps can be a good way to go with deeper pockets and a location that works. On top of a hill in a rural area and it gives the scope for distance listening, but if your limited reception is geographic, as in you live in a city like, as a good example, Belfast. It sits low, is surrounded by tall hills and small mountains. These sort of contain RF, but there is lots of it locally. The mast head preamps get overloaded by the very strong local signals, effectively shutting them down, gain wise, so the distant weak signals from just a few miles away die away. You might need serious filtering if, say you want aircraft, but live near a VHF pager. Marine listening just above the pagers suffers too.
The usual rules are antennas with gain, but for listening, wideband zero or lower gain antennas are needed. Losing signal in the cable is the first thing to sort. For receive only, you could even use cheap satellite cable. Its very low loss, thin and handy. Its bad features are you have to bodge the connectors to fit normal antennas. Adaptors are often rubbish outside unless really carefully waterproofed, and of course the impedance is wrong. For receive, that doesn’t really matter. What is well known, is that RG58 is, and always has been, pretty lossy stuff, but bendy, and easily fitted to connectors. Low loss transmit is crazily expensive.