I did a quick lash-up of the UHF FM transmitter module I received a few days ago which I was planning to use in a low-power Echolink node, mainly just to see if it worked. It did, but I discovered a small snag. The audio output isn’t squelched.

The Echolink software requires either normal squelched FM audio or a carrier operated squelch signal on one of the serial port control lines. As neither of those is provided I guess I am going to need to generate a squelch signal derived from noise. But as I am not knowledgeable enough about electronics to design my own circuit I am going to have to find one first. This appears easier said than done, though there seem to be a surprising number of patents on the subject.

It isn’t an urgent problem as I’m not in any hurry to build this project. I’ll probably have more enthusiasm for it once the gloomy autumn weather starts.

Julian Moss, G4ILO, is a regular contributor to AmateurRadio.com and writes from Cumbria, England. Contact him at [email protected].

Leave a Comment

Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter
News, Opinion, Giveaways & More!

Join over 7,000 subscribers!
We never share your e-mail address.

Also available via RSS feed, Twitter, and Facebook.

Subscribe FREE to AmateurRadio.com's
Amateur Radio Newsletter

We never share your e-mail address.

Do you like to write?
Interesting project to share?
Helpful tips and ideas for other hams?

Submit an article and we will review it for publication on AmateurRadio.com!

Have a ham radio product or service?
Consider advertising on our site.

Are you a reporter covering ham radio?
Find ham radio experts for your story.

How to Set Up a Ham Radio Blog
Get started in less than 15 minutes!

  • Matt W1MST, Managing Editor

Sign up for our free
Amateur Radio Newsletter

Enter your e-mail address: