Compression Driver protection Circuit

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Compression Driver protection Circuit

Post by ADLOG » Thu Apr 08, 2010 6:29 pm

Back in July 2007, I came across this topic of protecting compression drivers thru some means. I was not a member of this forum. The auther was djk. He suggested to protect a 50-60w driver, one would need the following: A Polyswitch, Pt.# REX110, a 2.2 ohm 15w resistor, and a #1156 automotive lamp. The Polyswitch is in series with the driver hot lead, and the series of the lamp and resistor is in parallel with the Polyswitch.

My application is to protect the Mid-HF driver in our Renkus-Heinz speakers. The power rateing is 15w RMS, or 30w Program, @ 8 ohms. What would be the proper values for the parts used in this protection circuit?

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Re: Compression Driver protection Circuit

Post by tommer » Wed Jan 12, 2011 11:18 am

the concept of using the resistor and "auto lamp" in series
is a similar thingy that HEATKIT used years ago in some
of the kits. It was cheap and effective secure way of
limiting current. Worked good too.

I forgot which kit i built that used the similar idea,
but it did work great !

I believe some of the old Hitchcock and old
Hitchcock built military tube testers used a
lightbulb as a fuse.... and some really early
6-volt car battery chargers used a "lamp"
as a regulator as well.

Pretty slick. Cheap too and reuseable.
I was brought up so po, we couldn't afford the O and R in poor...

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