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#1
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While doing some memory scanning of military frequencies tonight, I
was reminded how much I'd like to be able to optimize the squelch setting for each channel individually. As it is, I have to set the squelch to match the noisiest frequency on my scan list--even though that means I might be missing signals on the quieter frequencies. Very frustrating! I'm told that the AOR 7030+ can change the squelch setting automatically as it moves from one scanned frequency to the next. What a great feature! It's a shame this receiver isn't sold in the US anymore. A side note....several months ago I was actually thinking about buying a 7030+ and happened to see it still listed on Lentini's website. I called Lentini to find out if they could really get one for me. The guy I talked to said it would be no problem. It would be shipped to me directly from AOR USA's main facility in California. I didn't know what to make of this, as I'd heard that AOR USA no longer carried the 7030+. So, I called AOR USA and was told that I could not purchase the receiver through them. I then emailed Lentini and told them about this; yet, to this day, the 7030+ is still listed on their website (http://www.lentinicomm.com). Oh well.... Steve |
#2
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Steve wrote:
While doing some memory scanning of military frequencies tonight, I was reminded how much I'd like to be able to optimize the squelch setting for each channel individually. Can some VHF scanners do this? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#3
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While doing some memory scanning of military frequencies tonight, I
was reminded how much I'd like to be able to optimize the squelch setting for each channel individually. Some HF radios offer "syllabic squelch" which is not a response to ANY signal, but looks only for specific characteristics of voice (syllables) Harris 505 has this, (but no scanning) as do the Scientic Radio System units. Such radios do not respond to noise, so you find that you don't have to adjust squelch for day/night differences |
#4
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![]() Radioman390 ) writes: While doing some memory scanning of military frequencies tonight, I was reminded how much I'd like to be able to optimize the squelch setting for each channel individually. Some HF radios offer "syllabic squelch" which is not a response to ANY signal, but looks only for specific characteristics of voice (syllables) Harris 505 has this, (but no scanning) as do the Scientic Radio System units. Such radios do not respond to noise, so you find that you don't have to adjust squelch for day/night differences I was assuming that was why it's not a common feature. Squelch is by definition a threshold, and that threshold changes. That doesn't sit well with something preprogrammed. Michael |
#5
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![]() "Michael Black" wrote Radioman390 ) writes: While doing some memory scanning of military frequencies tonight, I was reminded how much I'd like to be able to optimize the squelch setting for each channel individually. Some HF radios offer "syllabic squelch" which is not a response to ANY signal, but looks only for specific characteristics of voice (syllables) Harris 505 has this, (but no scanning) as do the Scientic Radio System units. Such radios do not respond to noise, so you find that you don't have to adjust squelch for day/night differences I was assuming that was why it's not a common feature. Squelch is by definition a threshold, and that threshold changes. That doesn't sit well with something preprogrammed. Michael In a scan-set of utility frequencies, there are daytime freqs and night time freqs. In between, is a transitional area. A preprogrammed day-set could include from 10 mhz - 25 mhz, with the 10 mhz freq attenuated in memory and the rest of the day-set on pre-amp if desired. Conversely, a night time set could have 2-8 mhz on pre-amp and 10 mhz attenuated. This way, the squelch can be set to allow scanning w/o stopping on high background noise from frequencies in the transitional area. Jack |
#6
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In a scan-set of utility frequencies, there are daytime freqs and night time
freqs. This wasn't what I was talking about. Yes, DOD, CG and other HF users respond to different PROPAGATION characteristics by having "day" and "night" channels. What I was referring to was that the noise level ("noise floor") changes over time. For example on 11175 (which is a day AND night channel) I'd have to adjust the threshhold as the day went on, because an increase in background noise continued until after dusk. And then around midnight, the noise floor would drop and world-wide signals would come in. With my R71, I'd make two or three adjustments a day, at least. The RF 505 NEVER needed adjustment because it "sensed" voice rather than "sound". It, and my Scientific Radio Systems fixed-channel radios, hardly ever responded to lightning. The Icom would be triggered all the time. |
#7
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"Radioman390" wrote
In a scan-set of utility frequencies, there are daytime freqs and night time freqs. This wasn't what I was talking about. Yes, DOD, CG and other HF users respond to different PROPAGATION characteristics by having "day" and "night" channels. What I was referring to was that the noise level ("noise floor") changes over time. Yes and my reply wasn't a response to you alone, but to the poster's question in general.The noise floor changes often correspond to the fading of a band when it's time is done. This is almost always true at the extremities such as 4mhz and 20mhz. They will normally have the least amount of background noise floor durnig their respective best propagation times. Not a rule, just an observation. For example on 11175 (which is a day AND night channel) I'd have to adjust the threshhold as the day went on, because an increase in background noise continued until after dusk. And then around midnight, the noise floor would drop and world-wide signals would come in. With my R71, I'd make two or three adjustments a day, at least. Hard to make a generalization about a transitional frequency. That particular one is pretty quiet all the time, but I too have had loud and clear copy from aircraft over Egypt and Saudi on it, and only during the night here on the East coast. That is however also a feature of when aircraft are most active there, during the daytime in that area. The RF 505 NEVER needed adjustment because it "sensed" voice rather than "sound". It, and my Scientific Radio Systems fixed-channel radios, hardly ever responded to lightning. The Icom would be triggered all the time. Yes those were unique radios. But since that feature doesn't appear to be available in modern receivers, then the tactic of applying a mixture of pre-amp, no pre-amp and attenuation is a system that works well when a wider band of hobbyist scanning than only clear channel (day) or clear channel (night) is desired. The detection feature is used in transceivers today, but it's different because they operate with squelch "off" (all static, all the time) and still detect and hold on receipt of their address, its just not voice they're looking for. If I were guessing, I would say the voice-detect feature might have been abandoned because of its uncertainty in opening the squelch for weak and barely readable voice-calls. Jack |
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