A Short Lesson On Scanners Definitions -
Low band - 30 mhz to 50 Mhz VHF high band - 150 Mhz to 174 Mhz UHF band - 450 Mhz to 512 Mhz 700/800 - 700 Mhz to 900 Mhz Low band frequencies are heard best with straight antennas that are maybe 6 feet long. VHF highband frequencies are best heard with straight antennas that are maybe 2 feet long. UHF freqs are best heard with antennas that are maybe 1 foot long. (I forget what the exact lengths are - you can figure it out using the speed of light and the exact freq - I aint kidding - it is based on the speed of light). Since it is impossible to put a 6 foot antenna on a hand held scanner, some compromises have to be made. Perhaps a coil is added at the base of the antenna, or the antenna is cut to 1/4 or 1/8 of the optimum size. The same general compromises are required for VHF high and UHF antennas. More Definitions PL - Private Line DPL - Digital Private Line NAC - Network Access Code PL, DPL, and NAC are optional settings on some scanners. Older scanners never had these options. These options allow a user to listen to only 1 station on a shared channel. For example, Nantucket MA FD and Plymouth MA FD both use the freq of 154.43. If you have a newer scanner, you can set the PL to just hear Plymouth FD, or to just hear Nantucket FD. or you can leave the PL turned off, and hear both FDs. More Ideas Scanner reception can be very tricky. Generally speaking, you want the antenna as high as possible, and as vertical as possible. But sometimes you can get a better signal if you lean the antenna over. The best answer here is - play around - see what works best. How far can a scanner hear? That is another very tricky question. But consider this. The astronauts talked from the moon to earth with 10 watts of power IIRC. This tells us that very little power is needed when there is nothing blocking the path between the transmitter and the receiver. Us mere mortals on earth have to deal with hills, valleys, walls, basements, etc - all of which enjoy keeping radio waves away from our scanners. OK - class is over for now. -- You received this message because you are subscribed to the Google Groups "massfire" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/massfire. For more options, visit https://groups.google.com/d/optout.
