Getting A Vanity Call Sign
- Details
Amateur radio operators are issued call signs by the FCC upon qualifying for their Technician license, and have the option to be issued new call signs that reflect their new class when they upgrade to General or Extra. The form of call sign is limited by license class, where higher class of licenses allow simpler/smaller call signs. For instance, a Technician class licensee may be issued something like KX4XTT (often referred to as a two by three, two letters before the number and three after); however an Extra class licensee may have a call sign like W4BK (often referred to as a one by two). There are various call sign formats between these extremes, often limited by license class. You can view the "rules" by going to this link and clicking on "Sequential Call Sign System".
A person with a General, Advanced, or Extra license may have a Technician class call sign, but not the other way around. Most people, when upgrading their license, choose to keep their original call sign, and the rules allow for it. Others may request a new call sign be issued, but most prefer to choose their call sign if they are going to change it, which is where the Vanity Call Sign system comes into play.
Best Power Practices II
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In Best Power Practices I we discussed a variety of issues related to properly powering your gear. We covered the need for dedicated power wiring as well as the desirability of using standard connectors.
Power Wire Gauge
We previously discussed the need to utilize wire of the proper gauge for feeding power to our radios, and also the fact that conventional vehicles do not have wiring from the factory capable of carrying the current required for a typical mobile amateur radio. Utilizing that wiring will likely result in damage to the wiring over time.
So, you've decided to properly power your rig with dedicated wiring for your gear. But what kind? Certainly you want to use stranded wire in a mobile rig, as solid wire eventually suffers from the vibration of the vehicle and will become damaged over time. Stranded wire is also more flexible and tolerate of being routed through the vehicle. The insulation type is important, particularly in automotive applications, where temperatures (even in the cabin) can be quite high. Cross-Linked polyethylene (XLP), and Polyvinyl Chloride (PVC) will do the job, but plain polyethylene will break down at temperatures in the cabin, much less in the engine compartment.
Best Power Practices I
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Operating a mobile rig in a motor vehicle or as a base can create some interesting challenges, and while many installations may work, they may be optimal, and could potentially damage your radio or automobile. We’ll break things down into a few different topics.
Connecting Vehicle Power
Most motor vehicles are not really wired for an accessory that draws the current a typical mobile amateur radio will. Still, many of us have (or do) run our radio using the “Accessory” or “Cigarette Lighter” jack. That jack is typically rated for 10 amps, and for intermittent usage. A conventional amateur radio with 50 Watts of output will consume 11 amps or more. At best, you are maxing out usage, at worst exceeding capacity. Additionally, the adapter connection does not provide a solid ground or hot connection, often increasing current draw. There is little other wiring in the car that can handle that load either.
So, if you’re at or above capacity, why doesn’t the fuse blow? Because fuses require an excess of current for some sustained period of time. Even though the fuse isn’t blowing, the wiring is getting hot, and the insulation will eventually begin to break down.
Running power specifically for your radio is the best practice.
Power Connectors
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One of the interesting things about Amateur Radio is the nearly universal use of PL-259 connectors for base and mobile radio gear, at least that at or below the UHF end of the frequency spectrum. We typically utilize 50ohm cable, even if there are variations of loss across the frequency spectrum, diameter, etc.
One area we see very little standardization, especially across brands, is power connections. Almost all mobile and base gear runs off 12 volts, yet there are a multitude of connectors, having little more than the red for hot and black for ground color coding.
In addition, we will connect that equipment to a variety of sources, some making it obvious which connector is hot and which connector is ground. Others, like car batteries, often require a close look. Also, in some instances the wires are always properly color coded.
Because of these variables we can almost be certain, that if we tinker, change, or rearrange our radio gear very much, we WILL accidentally hook the wires up wrong and let the smoke out of some valuable piece of radio gear.
There are a number of ways to minimize, even virtually eliminate, this hazard. First, ALWAYS using color coded wire is a big plus. Red for hot, Black for ground. Make sure any power sources are similarly color coded, even if that means painting some nail polish on or around a the post of a power supply or battery.
Cross-Band Repeating
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Cross-Band repeating has great potential for use in EMCOMM, extending our ability to utilize handhelds as well as providing gateways to more distant repeaters.
First, a quick explanation of what cross-band repeating is: the use of radio equipment that can simultaneously transmit on one frequency what is received on the other, much as a normal repeater. The twist is that the two frequencies will be on different bands, usually 2M and 70cm. The reason for this, is the significant difference in frequencies allows the simultaneous transmit and receive with simple circuits, rather than large and bulky duplexors required for same-band repeating.
Many in our group, who can't directly reach the repeater with an HT, utilize cross-band repeat capability. To cross-band, merely run an HT in simplex on an appropriate 440Mhz frequency and on your mobile or base station set one VFO to the same simplex frequency as your HT and operate the other VFO as normally for the repeater. When the radio is in cross-band mode it will transmit everything that comes in on the repeater output to the 440Mhz frequency, and repeat everything from the 440Mhz frequency to the repeater. Your HT now has the same range as your base or mobile rig!
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