Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  
previous: Murdoch Kevin O'Connor is putting aside the... -- 5/14/2003 4:02 PM View Thread

Re: Opto-Coupler vs LDR

5/15/2003 6:23 PM
Rick Erickson
Re: Opto-Coupler vs LDR
I must be missing something here. What's the difference between an opto-coupler and an LDR?  
Most common opto-couplers I've seen in amplifiers are a package containing an LED and an LDR. The VTL-5C3 is a typical opto-coupler. I don't own any of Kevin's books, maybe I would understand the question better if I did.  
My preference is relay switching. Been using them for many years without problems. Advantages - lower "on" resistance, higher "off" resistance, linear frequency response, able to handle relatively large voltages and currents found in tube preamp circuits, easy to power an led across the relay coil for a simple status indicator. Relays can be very quiet if the circuit is designed properly. Certainly worth considering.  

Murdoch You didn't missed anything Rick, th... -- 5/15/2003 7:49 PM
stephen conner An Opto-coupler is normally taken t... -- 5/15/2003 9:24 PM