Albert, In the 30-50 MHz band, the antennas for a portable radio must be cut for proper operation, over a very narrow range of frequencies. The length of a whip antenna must be changed by 1/4-3/8 inch for every 1 MHz. Motorola still offers the NAB6064B "tunable" antenna for the MT1000 radio, which must be cut to length for the specific frequency needed. In other words, there is no such thing as a broadband antenna for low band, and the radio's PA could be damaged by using an antenna that is not the right length. The NAB6064B antenna costs about $23 from Motorola Parts. Call 800-422-4210 to order.
73, Eric Lemmon WB6FLY -----Original Message----- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Albert Sent: Friday, July 10, 2009 12:56 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Building HT antennas Hey guys, I posted this question over on the HT600e forum but didn't get anything. I was wondering if anyone here could be of assistance. I recently acquired a low band MT1000 for use on the 6m band. It has a nice new commercial antenna but I was wanting to do something a little better. No one that I can find supplies or can supply me with a better antenna for this radio. Even smiley antenna, my usual go to company for custom antennas for the Genesis line can't help me. So I was thinking of building my own. My first thought, since the antenna connector on the MT1000 is basically a 1/4-32 hole, I could thread a piece of aluminum round stock to create a base. Then I could just make a 1/4 wave whip from stainless rod. I know it would be silly long but it is a start. If I do this, do you think I should just use the standard 1/4 wave vertical formula? Would I need to compensate for the HT's lack of a ground plane? Any thoughts would be appreciated. Thanks Albert KI4ORI
