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THE AM BULLETIN BOARD => Technical Forum => Topic started by: Opcom on August 07, 2015, 11:56:33 PM



Title: audio-sensing squelch circuit
Post by: Opcom on August 07, 2015, 11:56:33 PM
What I want to ask about is the squelch project in this article. It sits between the receiver audio and the speaker, acts on part of the audio band, and looks for the syllable timing in speech to open the audio circuit.

The author says it works well. It's labeled for SSB but since it works only on the audio output can anyone think of a reason it would not do as well on AM?

I believe it is fair to discuss this concept using the material because the operation of the schematic is not so evident at a fast look


Title: Re: audio-sensing squelch circuit
Post by: N1NTE on August 08, 2015, 08:24:52 AM
Bought this kit a little while ago for use in a SSB project. Haven't built it yet but it might be worth a shot asking the seller how it would work on AM. There isn't anything mentioned in the instruction manual about any mode other than SSB.


http://www.ebay.com/itm/VOS-Voice-Operated-Squelch-Audio-Muting-Kit-Form-/321145239752


- Rob


Title: Re: audio-sensing squelch circuit
Post by: Opcom on August 08, 2015, 02:42:47 PM
I did ask. Let's see what comes back from Canada!
If it's the same thing that seems interesting.
Why not build yours? Should not be but one evening's fun.


Title: Re: audio-sensing squelch circuit
Post by: Pete, WA2CWA on August 08, 2015, 05:00:04 PM
You want tube or solid-state?


Title: Re: audio-sensing squelch circuit
Post by: Opcom on August 08, 2015, 11:20:49 PM
Tube is always worth considering first. Got a solution?

Those projects mentioned use ICs but there is no reason tubes could not be used if desired.


Title: Re: audio-sensing squelch circuit
Post by: Pete, WA2CWA on August 09, 2015, 03:09:00 AM
You might want to take a look at the squelch circuit in the Gonset Communicator II. I believe it used a single tube.


Title: Re: audio-sensing squelch circuit
Post by: N1NTE on August 09, 2015, 07:32:34 AM

Why not build yours? Should not be but one evening's fun.


It is on the To Do list along with a hundred other things (family, electronic, etc.) I have a pile of unbuilt kits (Softrocks, regen receivers, etc.) that I am looking forward to building this winter. Reviews for that eBay kit were good. I bought it to use in a 10m SSB remote base.

- Rob


Title: Re: audio-sensing squelch circuit
Post by: Opcom on August 09, 2015, 09:45:52 PM
You might want to take a look at the squelch circuit in the Gonset Communicator II. I believe it used a single tube.

The squelch circuit in the Gonset Communicator II is carrier operated and not the same kind of operation or result. The voice-detecting performance claimed in the article can not be approached with the Gonset circuit.
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