Hi Mark, According to my old Antenna Specialist catalog, what you have is a MINI-PAK series, half-wavelength, economy base station antenna. The photo shows the radials coming straight out, but I would guess there would be some drooping due to their weight. Here's some info on the ASPA2010 Frequency Range: 30 to 40 MHz Power: 500 watts maximum Gain: Unity Bandwidth: 2% of operating frequency Beamwidth: 75 degrees Matching Coil: dc grounded PVC jacket Feedpoint Impedance: 50 ohms VSWR: <1.5:1 Rated Wind Velocity: 67 MPH To use this antenna on 10 meters you may have to ADD length to the radials, not cut them. And you may have to add length to the vertical antenna portion as well in order to get it to resonate on 10 meters. If you shorten the antenna element and radials, it would work fine on 6 meters. FYI, their ASPB2010 product covered the range from 40 to 50 MHz. I don't have the instruction manual or cutting chart. What I would do is leave the radials alone and adjust the antenna for the longest possible length. Then hook it to a transmitter through an SWR meter and take some readings at various frequencies like 29.6, 29.3, 29.2, and 29.0. Based on that you can tell if the antenna element is too long or too short and go from there. If you luck out, the SWR will be acceptable. If the SWR gets higher as the frequency gets lower, then you'll have to figure out a way to lengthen the element and radials and try again. 73 and Good Luck! Eric KH6CQ
--- On Mon, 8/11/08, mark_n2mh <[EMAIL PROTECTED]> wrote: From: mark_n2mh <[EMAIL PROTECTED]> Subject: [Repeater-Builder] Low Band Base Antenna Info Wanted To: [email protected] Date: Monday, August 11, 2008, 2:57 PM Hello to the Group, Does anyone have any information or a cutting chart for the following antenna? I have one and would like to put it into service on 10 meters. It was given to me without any info or radials. It is definitely used but appears to be intact. A quick web search turned up nothing. Sticker Info on antenna: Antenna Specialists Dallas TX 75247-6780 ASPA 2010 30-40 MHz 9209508 Serial xxxxx-x It looks like a commercial version of a CB base antenna. The vertical radiator is a series of telescoping aluminum tubing pieces held in place with hose clamps. Maximum extended length of the vertical element is approximately 21 feet. Minimum contracted length is approximately 5 feet. The antenna uses 4 radials and the radial clamps appear to accept 5/16 inch rods. (I'm not sure if the radials are supposed to stick out straight or droop at some desired angle.) If nobody has any info, does the following tuneup procedure seem correct? 1. Cut a set of radials for 1/4 wL at 35 MHz. 2. Adjust the vertical radiator for best SWR within 30-40 MHz. 3. Measure and record vertical element, radial lengths, and frequency. 4. Scale recorded dimensions to the desired 10 meter frequency. Thanks and 73, Mark, N2MH
