Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Solid State => Topic started by: tubesornothing on July 07, 2009, 11:30:33 am

Title: Using optocouplers for switching
Post by: tubesornothing on July 07, 2009, 11:30:33 am

I notice mojo makes a generic switch board using roach style optocouplers.  Anyone ever try this?  Care to share what you used for the photocell and LED?



https://www.mojotone.com/item.asp?pid=570930&pg=44991&id=5352105

Title: Re: Using optocouplers for switching
Post by: tubesornothing on July 15, 2009, 05:31:30 pm

So found out some more info.  15 ohms on resistance, 5Mohms off resistance and can handle 150VDC.  Thats pretty good.

Hmm, looking up in digikey, it looks like the best I can find has 5-10k on resistance at 10lux , that might be OK for in series, but for shunt, that'll leak.  I wonder how much lux an LED puts out, and if it can drive it down to like 100R?

With a photocell I found in the bucket it seems to on/off times might be satisfactory.  I guess it'll take some experimenting.

Title: Re: Using optocouplers for switching
Post by: PRR on July 15, 2009, 06:17:37 pm

> 15 ohms on resistance, ..  Thats pretty good.

Also pretty unlikely.

I've worked hard to get a photo-R down to 500 ohms. 100 is possible. 5 is fantastic.