R30 Squelch on HF USB?

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Mike445

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Hey y’all. I’m interested in buying the R30 but would like to ask a question I can’t seem to find an answer to! I want to scan some specific HF USB frequencies (e.g-11.175USB) alongside my UHF military air frequencies. Does squelch work on USB HF frequencies? I can’t do it with my R10. On USB HF it’s open squelch.
Thank you!
Mike
 

AOR-262

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@Mike445

I can't comment on the R30; however I do say that the R30 is the little handheld brother of the R8600 so I believe they kinda work using the same system. I regularly listen to HF (below 30MHz) using my R8600 and turning the Squelch up to lose the background 'hissing' noise pretty much wipes that frequency out. What I do use which works really well is 'VSC' (Voice Squelch Control). You can't adjust the level of the VSC but it does work well in silencing the radio and detecting when audio is present and opening up the frequency when audio is heard. No idea if the R30 has the 'VSC' feature.
 

Mike445

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@Mike445

I can't comment on the R30; however I do say that the R30 is the little handheld brother of the R8600 so I believe they kinda work using the same system. I regularly listen to HF (below 30MHz) using my R8600 and turning the Squelch up to lose the background 'hissing' noise pretty much wipes that frequency out. What I do use which works really well is 'VSC' (Voice Squelch Control). You can't adjust the level of the VSC but it does work well in silencing the radio and detecting when audio is present and opening up the frequency when audio is heard. No idea if the R30 has the 'VSC' feature.
Thank you for the reply. Yes the R30 has VSC and so does my R10! I’ll have to play with it. The same thing happens when I try to squelch on my R10 the channel fades away. Have a great day.
Mike
 

bbo14

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I have an SGC DSP unit that includes a very good voice squelch, using the syllabic detection capability. I switch it ON and nothing opens it except the human voice. I am about to route ALL my radios thru it, FM, AM, SSB. After listening to white noise for 50 years, I'M TIRED !! These units show up on EBAY every once in awhile. I love mine. There are some others out there, but I don't know if they work as well as the SGC.
 

bbo14

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Thanks Mike. Just do an EBAY search for "syllabic squelch" or "voice squelch" and you may score the non-SGC one as well.
 

majoco

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The very popular and common Codan 6801 transceiver down here has a very good voice squelch and I just happen to have the schematic and the layout of the PC board - wouldn't be hard to duplicate as it doesn't use anything special, just OTS components and could well work on a bit of proto board.

PCB and info.jpgSchematic 1.jpg
 

prcguy

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There are kits available for a syllabic squelch circuit with circuit board and all parts. I have a couple and will post the source when I figure out where I got them.

The very popular and common Codan 6801 transceiver down here has a very good voice squelch and I just happen to have the schematic and the layout of the PC board - wouldn't be hard to duplicate as it doesn't use anything special, just OTS components and could well work on a bit of proto board.

View attachment 82780View attachment 82781
 

vagrant

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I believe they were previously sold on eBay by someone out of Canada. I have not found one of late and wish I would. I have forgotten resistor color code values years ago, so it would take me a little bit longer with the kit schematic.

There is one on eBay now that someone built into an enclosure with a speaker. They want $150 plus shipping though. I don't need one at that price. (The VOS is the board on the left)
 

WB9YBM

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Usually squelch needs a carrier that it can detect (like on AM & FM) which will then be used to mute or un-mute a speaker. The last time I investigated squelch circuit for SSB I found nothing that worked all that well (although I admit this was many years ago so something may have been developed since then). Theoretically the background hiss heard in a receiver when there's no signal being received can be amplified and rectified to act as a type of squelch, based upon theory that when there's a strong enough signal to over-ride the background hiss and given the more widely spaced signals represented by speech, the circuit will un-mute the speaker.
 

bbo14

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The squelch used on HF SSB is a "voice activated" or "syllabic" squelch. It is all but impervious to noise, static crashes, tones, etc. It operates on the principle of the 3.5 to Hz syllabic rate of the human voice.

The usual squelch operates on an AGC voltage change, or, in the case of FM, an amplification and detection of noise, usually 7-8Khz or above, and application of that to silence the audio until an incoming signal overcomes the noise, reducing the applied detected voltage and opening the squelch, thus passing the audio.

The syllabic squelch was developed for the transoceanic aircraft industry and maritime industry; both of whose users had better things to do than listen to white noise constantly. It interfered with their more important duties of navigation and safety.
 

prcguy

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A syllabic squelch operates by sampling noise in the 4KHz or above range, then two or three voice range frequencies like 400Hz, 1KHz, etc. Each frequency range is tightly filtered, rectified then applied to a switch, then to an "and gate". When there is presence of voice range audio and absence of noise the squelch opens. A couple of radios stand out with excellent syllabic squelch, the military PRC-70 manpack and all the Harris RF-5000 series including the RF-5020/RF-5022 and the PRC-138 manpack.

I found my syllabic squelch kit which I assembled into a box then found I bought a spare kit still in package. I'll open the package later and post the company info if its there.

The squelch used on HF SSB is a "voice activated" or "syllabic" squelch. It is all but impervious to noise, static crashes, tones, etc. It operates on the principle of the 3.5 to Hz syllabic rate of the human voice.

The usual squelch operates on an AGC voltage change, or, in the case of FM, an amplification and detection of noise, usually 7-8Khz or above, and application of that to silence the audio until an incoming signal overcomes the noise, reducing the applied detected voltage and opening the squelch, thus passing the audio.

The syllabic squelch was developed for the transoceanic aircraft industry and maritime industry; both of whose users had better things to do than listen to white noise constantly. It interfered with their more important duties of navigation and safety.
 

majoco

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What prcguy said. If you look at the schematic diagram in my post #7 you see that there are two channels which pass the frequencies in the bands 590 to 1040Hz and 2.0 to 2.7kHz. If an incoming signal has some energy both of these bands then the original audio is passed through to the output. One disadvantage is that on weaker signals you lose the first few syllables.
 

vagrant

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I read the manual for the R30 and it does not list VSC for SSB. Can you confirm it does? Perhaps there was an update, or perhaps not. The R8600 notes that VSC is an option for SSB, but there is a price difference between the two devices.
Thank you for the reply. Yes the R30 has VSC and so does my R10! I’ll have to play with it. The same thing happens when I try to squelch on my R10 the channel fades away. Have a great day.
Mike
 

Mike445

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I read the manual for the R30 and it does not list VSC for SSB. Can you confirm it does? Perhaps there was an update, or perhaps not. The R8600 notes that VSC is an option for SSB, but there is a price difference between the two devices.
I never bought it. Not yet. My R10 has VSC on USB. I cannot confirm.
Mike
 

vagrant

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Thanks for that. I wasn't sure if you had and this seemed like the best thread to check versus a new one.
 

ridgescan

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@Mike445

I can't comment on the R30; however I do say that the R30 is the little handheld brother of the R8600 so I believe they kinda work using the same system. I regularly listen to HF (below 30MHz) using my R8600 and turning the Squelch up to lose the background 'hissing' noise pretty much wipes that frequency out. What I do use which works really well is 'VSC' (Voice Squelch Control). You can't adjust the level of the VSC but it does work well in silencing the radio and detecting when audio is present and opening up the frequency when audio is heard. No idea if the R30 has the 'VSC' feature.
VSC in my experience with my R8600 is useless in HF. Even using NB random pops will open VSC constantly.
I can utilize squelch on my old faithful R75 though, IF I engage NB, and combine ATT and preamp 1 then put squelch right up to the very edge of opening. Most of the time the stars will align and only voice will open squelch. This enables me to monitor an HF utility with total quiet. Good old R75 surpasses the R8600 in this respect.
 

vagrant

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What about when you scan HF AM/SSB freqs (memories) with VSC enabled? Like you said a pop will open it, but for the most part is it locking on each freq, or sweeping through them?
 
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