TIPS & LINKS
PROTECT YOUR EQUIPMENT
1. NEVER UNPLUG SPEAKERS WHILE EQUIPMENT IS POWERED UP
Powerful speakers are constructed similar to the coils that ignite the spark plugs in most cars. They typically consist of coils of wire wrapped around a core or magnet. If there is the slightest amount of energy being applied to the speaker when it is unplugged, a voltage surge of several thousand volts can be generated and fed back into the equipment. Every attempt is usually made to bypass that surge without adversely affecting sound quality. However, there is only so much that can be done.
It is very common to have eager “assistants” come up to “help” breakdown after a presentation, and they often start off by unplugging things, including speakers. Please inform those “assistants” NOT to unplug ANYTHING until ALL power had been removed.
2. Always transport your equipment in protective cases designed specifically for the purpose.
3. You may want to check supply voltage and the voltage settings at the equipment power connection BEFORE plugging in your equipment, especially if travelling to different countries. Some equipment has over-voltage and under-voltage protection circuitry, many do not. (Hilton MA220s will shut down the output drivers if over-voltage, over-current, over-temperature or a DC bias are detected.)
4. Check the impedance of your speakers.
As speakers age, the varnish insulation on the windings tends to breakdown, causing potential shorting between windings, which often reduces the impedance of the speaker to the point where they may damage equipment or cause it to go into shutdown mode. This can often be done with a simple ohm meter. However, this may not account for dynamic impedance changes as speakers warm up or are driven at varying frequencies.
SOME USEFUL LINKS
Square Dance Teaching Aids
Caller Lab Definitions - Mainstream (.PDF)
Caller Lab Definitions - Plus (.PDF)
Caller Lab Definitions - Advanced (.PDF)
Caller Lab Definitions - Challenge 1 (.PDF)
Caller Lab Definitions - Challenge 2 (.PDF)
Caller Lab Definitions - Challenge 3 (.PDF)
Round Dance Teaching Aids
Harold & Meredith Sears Round Dance Figures & Styling