Page 1 of 1

Jen HF Modulator with Fuzz and Boost mods

Posted: Tue Aug 12, 2025 11:17 am
by moid
Hi everyone

Hope you're not melting at the moment (the UK is having another dreadful heatwave and I'm hiding indoors so thought why not entertain/annoy the good folks of I Love Fuzz with a demo of a fuzz/ring modulator pedal thatI've built?

[youtube]www.youtube.com/watch?v=KqFIcac1ajM[/youtube]

This a demo of a Jen HF Modulator effect (the original circuit is from the mid 1970s) and is an audio rate tremolo with some fuzz in it - it creates some delicately odd fuzz sounds; I would describe it as being an entry level ring modulator for people that don't like ring modulators! I modified it to have a clean boost and a fuzz option. If you want to build your own then please see the vero layout that I've drawn:

https://imgur.com/EBsNyvn

This is heavily based on the work of Mirosol and Rocket 88 from the https://tagboardeffects.blogspot.com/ site.

Re: Jen HF Modulator with Fuzz and Boost mods

Posted: Tue Aug 12, 2025 11:57 am
by Chankgeez
Who doesn't like ring modulators? :mad: :lol:

(Nice job, moid! :thumb: )

Re: Jen HF Modulator with Fuzz and Boost mods

Posted: Tue Aug 12, 2025 12:13 pm
by moid
Thanks Chank - It's not really a ring mod, but it sounds similar ish and isn't a well known circuit and is pretty easy to build so I'm happy to recommend it.

Re: Jen HF Modulator with Fuzz and Boost mods

Posted: Tue Aug 12, 2025 7:50 pm
by EggSaladKing
This is a really cool circuit! I think I'll have to breadboard it out really soon.

Re: Jen HF Modulator with Fuzz and Boost mods

Posted: Wed Aug 13, 2025 3:37 pm
by moid
Thanks! However please use the below layout - the nice people at DIYStompboxes noted I had forgotten to add a rather important capacitor and resistor (I added them to my build, but not the vero layout!) so please use the below instead. There is some debate about whether the Intensity knob is wired correctly... but it does work as exepcted, so maybe that doesn't matter...

Image