On Wed, 21 Jan 1998 14:43:02 -0600, you wrote:

>I am using a 16C84 PIC to create a light bar for the 5 marker lamps (Cabover
>lights) on top of a Chevrolet Truck. The lights scroll left or right when
>that respective blinker is on. They also all blink in sync with the
>Emergency Flashers and are all on solid with when the parking lamps are on
>(with no blinker or flashers). For the record, I have 3 inputs:  left /
>right blinker, and parking lights.
>
>The 5 light outputs from the PIC are input into a 74LS04, Hex Inverter. The
>5 outputs of the Hex Inverter drive the coils of 5 Radio Shack 5VDC Reed
>Relays (part# 275-232).  The relay contacts are passing 13 to 13.8V to the
>lights. The current for each light is about 275ma (.275 Amps).
>
Reed relays are not really designed for load switching. Remember that
the inrush current for a 275mA lamp load may be a lot more due to the
low resistance of the cold filament. 
Use Transistors or MOSFETs to switch this kind of load - smaller, more
reliable and probably cheaper as well!
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   _/ L_/  Mike Harrison / White Wing Logic / wwl@netcomuk.co.uk  _/ L_/
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