[sdiy] Vactrol vs H11F1M optoFET

[Mike Bryant]

On a related note, has anybody experience using these :

https://www.digikey.co.uk/en/products/detail/onsemi/H11F1M/1793945

Upsides and downsides ?
________________________________
From: Synth-diy <synth-diy-bounces at synth-diy.org> on behalf of crystal via Synth-diy <synth-diy at synth-diy.org>
Sent: 23 October 2025 22:31
To: mark verbos <markverbos at gmail.com>
Cc: synth-diy at synth-diy.org <synth-diy at synth-diy.org>
Subject: Re: [sdiy] opto isolator "Vactrol" tester


They're not labeled, but, i think they are that same part. I had some very mixed results , but, since i bought a large bag of them, i just threw the really slow parts in their own envelope. Since they were for my own circuits i liked the (occasional) lower on resistance.

Hadn't though to shine a light on them externally. Next time...

Crystal

On 10/20/2025 5:06 AM, mark verbos wrote:
I have had VERY unreliable experience with the Silonex parts. I used NSL-32SR3 which are meant to be the fast ones but I had places where they would take several seconds to decay. Oddly, it made a difference if I had them in an inline resistor verses as one part of a voltage divider. Also, not necessarily a bad thing, but their on resistance is much lower than in the Vactec/PerkinElmer/Excilitas ones.

Mark




On Oct 19, 2025, at 10:58, crystal via Synth-diy <synth-diy at synth-diy.org><mailto:synth-diy at synth-diy.org> wrote:


Can someone point to a testing circuit for "Vactrols?"

I bought a bag full of Siliconex optos years ago, they are all over the map in response time.

I had tested quite a few in a very crude breadboard setup, mostly just looking at on/off resistance timing and off resistance and then putting them in envelopes with details written on them. I'm sure i could do that again, i'm just wondering if it's been done better.


thanks,

 Crystal

________________________________________________________
This is the Synth-diy mailing list
Submit email to: Synth-diy at synth-diy.org<mailto:Synth-diy at synth-diy.org>
View archive at: https://synth-diy.org/pipermail/synth-diy/
Check your settings at: https://synth-diy.org/mailman/listinfo/synth-diy
Selling or trading? Use marketplace at synth-diy.org<mailto:marketplace at synth-diy.org>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://synth-diy.org/pipermail/synth-diy/attachments/20251023/c4b68733/attachment.htm>