Message posted by lone wolf on July 14, 2005 at 23:46:50 PST:
Milcom is Larry Van Horn & Bob Grove's list. [You may remember Bob Grove from that Area 51 special, er, need I say more.] I haven't been on the list for a few years (too much irrelevant neocon crap). I've found it more useful to join lists on yahoogroups that are specific to the area that you want to scan. For Nellis, the list on DLR is better. Not all the DLR frequencies are used, but if you have them programmed, you won't miss anything. Anything new in the ranges I find I always post, unless of course it comes from Groom. You can google the scantenna to get opinions. It's a bicone instead of a discone for most of the band. A bicone needs a balun. The impedance match isn't so good (75 ohm versus 50 ohm). The real problem with large discones/bicones and the scantenna is that they pick up FM broadcast signals, and these signals will desense all but the highest end scanners. The AT-197/GR is better for mil air since it is a smaller discone, i.e. cut above the FM broadcast band. It's also what the USAF uses, though they pay the full $1k for new ones. For civil air band, one of the guys on the list (who can speak up if he wants) has a J-pole cut for the civil air band. It can just barely pick up the Janets as they land at Groom, from a location in Vegas I wouldn't consider all that optimal. You will note the scantenna has no specs. The AT-197/GR is spec'd at -0.3dB. It is generally accepted in commercial antennas to specify the gain relative to a 1/2 wave dipole, so the AT-197/GR is just slightly worse than a dipole, but it maintains its gain and impedance over the mil air band. [The dbi gain is relative to a mythical isentropic radiator, and tends to be used on consumer gear since the number is higher.] The glass like thing near the top is a lightning arrestor. Note that the AT-197/GR can be dissasembled, i.e the lower elements unscrew and the top hat pops off. This is so the antenna can be used by the military in the field, that is, it comes apart for easier transport. The AS-1405 is also designed for use in the field. Some of the longer elements can be retracted. The antenna is then placed in a plastic case that is molded to the shape of the antenna. The nice thing about the AS-1405 is that it uses a N connector, which is commonly available. Only the military uses the HN connector, so you either have to modify the antenna or get a HN to N adapter. I know Nellis' 99th Communications Squadron surfs my site, so I assume they read this forum. Come on guy and give us a cool frequency or two...
In Reply to: Re: military/area51 frequency questions posted by truckertom on July 14, 2005 at 14:30:37 PST:
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