Video Amplifiers for the Mirror Screw
The light sources for mirror screws based on my work, consist of a dozen or more of high brightness LEDs, in
colors or white, typically connected in parallel or series-parallel. Shown here are two amplifiers, capable of
handling the full range of video frequencies for as many as 40 LEDs in various series/parallel hook-ups. The
upper circuit is one developed by Peter Smith of Scotland, member of the NBTV and has been well proven by the
successful use by of many of the members in the NBTV. In its original form, the circuit could also separate sync
pulses from the video signals. In my method of operation however, sync is not required, so those associated
components have been removed. Club members are able to purchase printed circuit boards for Peter Smith's
amplifier at very low cost.
The amplifier in the lower portion of this schematic is one I developed that uses an operational amplifier capable
of providing up to 3 amperes output along with a wide frequency range. I have actually used this amplifier
successfully more than a dozen times and for as many as 36 LEDs.
produces positve 15 volts at a relatively high current of .3 amperes peak. It also provides a negative 5 volts
at .1 amperes. (PY)