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Welcome Skyler! Congratulations on your Extra ticket. If you're interested in antennas a lot I would obtain the ARRL Antenna Book, either new or used, they're all good. Regarding building a yagi - here are some basics to play with: Driven Element = 1/2 wavelength (468/F (MHz))...

The NB on my IC-7000 does a fantastic job in my mobile. Works as good as the NB on the old FT101E. Mike

Done properly, the center conductor should be the same length as the PL-259's center pin and soldered firmly. In other words you should see the end of the cable center conductor in the PL-259's center pin. Question: If the center conductor doesn't show any solder and you cannot see the...

Attached is a pdf scan from the 1964 ARRL Antenna Book showing a suggested manual antenna rotor system. Page 274 shows a right angled pulley (probably using right-angle gearing) to turn the antenna (Fig 12-12(c), and the next page shows a Mechanical Direction-Indicator System (Figure 12-38)...

Tnx Capt, There usually is a high impedance value for an amp input. May go as low as 10K. Maybe it is 50K to match the transformer impedance value? Memories from my OP Amp days in college. Mike

UxCow, I don't understand the problem/question. There are two resistors and two pots shown in Figure 4. The lower left pot is 100 ohms and is the Amp Control on the base bottom. The other pot is the 500 ohm Audio Output Control on the top of the mic base. The other two fixed resistors are a...

For additional information see Eham reviews: http://www.eham.net/reviews/detail/311. Some say it works, others have comments on tuning. The 11 Meter unit many cover the 40 channels OK without a tuner, however the signal would be no better or worse than a 1/2 wave dipole. Reading some of...

We used to have a saying at work: 100 Watts, 100 feet, 100 miles.

What M42 is implying is to wrap the PL-259 connector where it connects with the UHF Female socket (part E in your diagram) to seal the connection from moisture/weather intrusion. You need to wrap it from the UHF Female socket through the PL-259 and an inch or so on to the coax itself. Remember...

Merry Christmas and Happy New Year to you too BammBamm, and everyone on the forum. 73, Mike

I got around it by feeding the J-Pole with a 4:1 coaxial balun. Also seems to help increase the bandwidth.

Sounds like RF getting in. Is the speaker wire shielded? I had speaker problems with RF with a stereo system, and replaced the 2-conductor speaker wire with shielded microphone wire, (shield with one conductor). Not exactly the same problem, but the RF may be affecting an OP Amp within. Just...

Like Ratso asked: What license class did you pass? We can go from there.

Hi BJ, Go here to make Windows 8 get that Windows 7 Desktop look back: How to Make Windows 8 or 8.1 Look and Feel Like Windows 7

It looks like there is an insulator between the elements. If so, short them out. The dipole needs to be a one piece 1/2 wave length element with the shield of the SO-239 connector mounted at the mid point. Your halo will then start to resonant with a lower SWR. Adjust the gamma match for...

That's about right. Using the RF line-of-sight formula and you'll get a similar result. The formula is: SQRT(2 x Antenna Ht (in ft)) x 1.15. Thus SQRT(2 x 25) x 1.15 = SQRT(50) x 1.15 = 7.07106 x 1.15 = 8.132 miles. If you have a tower at Site A and a tower at Site B, then the antenna...

The UHF antenna should be OK since it is mounted ahead of the metal mast. Regarding the 2-Meter beam, you can mount it with the antenna about 20 degrees off of vertical to minimize any reaction. The antenna does not need to be perfectly vertical to work as a vertically polarized antenna...

Capt, I think the 'direct feed' implied that there are two coax runs: LMR-400 for the 2-Meter, and RG-8X for the UHF antenna. Something else to take into account: Bigloud, you are feeding the 144 MHz antenna with a lower loss cable than the UHF antenna. If anything the UHF antenna...

As long as the guy wires are not resonant at 10 Meters there should be no problem or interaction. It's in your ARRL Antenna Book in the "Building Antenna Systems and Towers" section. There should be a highlighted page labeled "Resonance in Guy Wires" that shows the non-resonant lengths table...

That's not surprising! You see a quarter wave antenna for 2M is a 3/4 wave antenna for 440 MHz (i.e. 148 MHz x 3 = 444 MHz). Same principal as a 33 ft vertical is a 1/4 wave at 7 MHz (40 Meters) and a 3/4 wave at 21 MHz (15 Meters). The 1/4 wave will produce 0 db gain, and the 3/4 wave will...