[digitalradio] Re: So there I was -
Hi Jose and all, --- In digitalradio@yahoogroups.com, Jose A. Amador [EMAIL PROTECTED] wrote: With packet forwarding, there was noone even attempting to park on a HF forwarding frequency. Common sense prevailed (even when a few crazy contesters sometimes attempted to overpower the BBS forwarding, specially on CW and RTTY contests. Nobody even whined about it). Common sense is what seems to have being lost nowadays I'm afraid Jose. As I remember, packet BBS's were not so few. Quite a few could be found between 14090 and 14115, just to remember the 20 meters activity. I have been a BBS sysop using only radio links since 1991 (three FBB/JNOS BBS's and multiband nodes, and cooperated in setting up another three) and operated in several bands in different seasons. Indeed a big portion of 20m digital subband was full of them. There are still a few around. Jose, CO2JA PS: Doing whatever is interesting, fun or novel in ham radio since 1972. OK Jose, I have been a licensed radio ham since 1983 and an SWL since 1970. Also, hoping this day is not the start of another anti-Winlink rant flood campaign on digitalradio. Please, spare us the undeserved suffering...this is not an appropiate forum for that anti-Winlink whining. Most of us on this list are NOT Winlink 2K MBO operators. It shouldn't start anything since this is really an argument about PACTOR 2 or 3 versus soundcard modes and not about Winlink2000. If anyone wants to argue against Winlink2000, he will start arguing very soon about PSKmail, ALE or any other messaging system that might be developed because they are very similar systems. Arguing against a system one cannot understand, use or does not like, does not promote digital and amateur radio at all. There are many others who want to use messaging systems. After all amateur radio is not only about voice QSOs, RTTY, PSK and all the variants, it has many aspects, many modes and we should all be a bit more tolerant since we are only doing a hobby here and if sometimes we cannot avoid the hidden transmitter syndrome (which by the way does not cause problems all that often) and cause some QRM to each other it is not the end of the world. Some seem to forget the most important Radio Amateur Rule about Courtesy. 73 de Demetre SV1UY
[digitalradio] just a reminder that the sked page exists
Hi folks, just a reminder that the sked page exists http://www.obriensweb.com.drsked/drsked.php Here are a few examples from yesterday... MM/DD UTC 09/16 04:07 KD4ULB K2NCC K0YNE QSO Olivia 500/16 7072.5 09/16 02:30 VK5OA ZL1PHD on Olivia 8-500 09/16 02:29 VK5OA ZL1PHD calling CQ 141095+750 good sig. Got wax in ears!! 09/16 01:12 K3UK 30M KC0HLN de VE7NS PSK31 09/15 21:14 K3UK 140777, CQ MT63 (500 bw) 09/15 20:27 KD4ULB TG9AKH CO2GL QSO MFSK16 14073.4 09/15 19:02 K3UK 14072 Olivia K2MO DE WB2HNP SK CL 09/15 18:35 W8TAH hi andy - you around? 09/15 16:39 K3UK Great Charlie, JT65A very active on 20 today. 09/15 16:36 N0ZC Andy, thanks for the great JT65A guide! I'm on the air at last with it. Charlie 09/15 14:03 G0DJA /cq k3uk You there Andy? 09/15 13:27 K3UK QRV...testing Olivia on 14077 (dial). -
[digitalradio] Re: So there I was -
Hi, I am QRV now and until 15.00z at 14.105 KHZ (center frequency) on PACTOR1, 2 or 3. I plan to do the same every Sunday from now on. You are all invited for a QSO. 73 de Demetre SV1UY
Re: [digitalradio] QRV MT63
[EMAIL PROTECTED] wrote: I will be monitoring 14,077.5 tomorrow. Today the only thing I heard was a noise that sounded like someone playing a flute badly. That was probably JT65A or one of the other WSJT modes. Dave (G0DJA)
[digitalradio] Re: just a reminder that the sked page exists
That should be http://www.obriensweb.com/drsked/drsked.php--- In digitalradio@yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: Hi folks, just a reminder that the sked page exists http://www.obriensweb.com.drsked/drsked.php Here are a few examples from yesterday... MM/DD UTC 09/16 04:07 KD4ULB K2NCC K0YNE QSO Olivia 500/16 7072.5 09/16 02:30 VK5OA ZL1PHD on Olivia 8-500 09/16 02:29 VK5OA ZL1PHD calling CQ 141095+750 good sig. Got wax in ears!! 09/16 01:12 K3UK 30M KC0HLN de VE7NS PSK31 09/15 21:14 K3UK 140777, CQ MT63 (500 bw) 09/15 20:27 KD4ULB TG9AKH CO2GL QSO MFSK16 14073.4 09/15 19:02 K3UK 14072 Olivia K2MO DE WB2HNP SK CL 09/15 18:35 W8TAH hi andy - you around? 09/15 16:39 K3UK Great Charlie, JT65A very active on 20 today. 09/15 16:36 N0ZC Andy, thanks for the great JT65A guide! I'm on the air at last with it. Charlie 09/15 14:03 G0DJA /cq k3uk You there Andy? 09/15 13:27 K3UK QRV...testing Olivia on 14077 (dial). -
[digitalradio] Something way cool from HF Link Network
Just in case you missed this recent development Several hams now have full time ALE stations that when they detect an ALE station, they report the reception almost immediately to a web page. Today, I began a ALE sounding from 80 to 10M and within a couple of minutes I had Internet confirmation that two stations heard me. Both stations told me what band and what my signal was. Station that Heard me Signal Report WA3MEZ: [15:02:52][ FREQ 07 MHz] [SND][TWSK3UK] BER 30 SN 08 KM4BA: [15:03:55] [FREQ 10 MHz][ SND][TWS] [K3UK] BER 28 SN 08 Very useful. Check http://hflink.net/qso/ -- Andy K3UK www.obriensweb.com (
Re: [digitalradio] Re: just a reminder that the sked page exists
Still got errors!!! http://www.obriensweb.com/drsked/drsked.php Hopefully no extra characters. On 9/16/07, Andrew O'Brien [EMAIL PROTECTED] wrote: That should be http://www.obriensweb.com/drsked/drsked.php--- In digitalradio@yahoogroups.com digitalradio%40yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: Hi folks, just a reminder that the sked page exists http://www.obriensweb.com.drsked/drsked.php Here are a few examples from yesterday... MM/DD UTC 09/16 04:07 KD4ULB K2NCC K0YNE QSO Olivia 500/16 7072.5 09/16 02:30 VK5OA ZL1PHD on Olivia 8-500 09/16 02:29 VK5OA ZL1PHD calling CQ 141095+750 good sig. Got wax in ears!! 09/16 01:12 K3UK 30M KC0HLN de VE7NS PSK31 09/15 21:14 K3UK 140777, CQ MT63 (500 bw) 09/15 20:27 KD4ULB TG9AKH CO2GL QSO MFSK16 14073.4 09/15 19:02 K3UK 14072 Olivia K2MO DE WB2HNP SK CL 09/15 18:35 W8TAH hi andy - you around? 09/15 16:39 K3UK Great Charlie, JT65A very active on 20 today. 09/15 16:36 N0ZC Andy, thanks for the great JT65A guide! I'm on the air at last with it. Charlie 09/15 14:03 G0DJA /cq k3uk You there Andy? 09/15 13:27 K3UK QRV...testing Olivia on 14077 (dial). - -- Andy K3UK www.obriensweb.com (QSL via N2RJ)
Re: [digitalradio] Re: just a reminder that the sked page exists
That`s better Andrew can read it now , suppose had better start using it also Mike gm6ofo Andrew O'Brien [EMAIL PROTECTED] wrote: Still got errors!!! http://www.obriensweb.com/drsked/drsked.php Hopefully no extra characters. On 9/16/07, Andrew O'Brien [EMAIL PROTECTED] wrote: That should be http://www.obriensweb.com/drsked/drsked.php--- In digitalradio@yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: Hi folks, just a reminder that the sked page exists http://www.obriensweb.com.drsked/drsked.php Here are a few examples from yesterday... MM/DD UTC 09/16 04:07 KD4ULB K2NCC K0YNE QSO Olivia 500/16 7072.5 09/16 02:30 VK5OA ZL1PHD on Olivia 8-500 09/16 02:29 VK5OA ZL1PHD calling CQ 141095+750 good sig. Got wax in ears!! 09/16 01:12 K3UK 30M KC0HLN de VE7NS PSK31 09/15 21:14 K3UK 140777, CQ MT63 (500 bw) 09/15 20:27 KD4ULB TG9AKH CO2GL QSO MFSK16 14073.4 09/15 19:02 K3UK 14072 Olivia K2MO DE WB2HNP SK CL 09/15 18:35 W8TAH hi andy - you around? 09/15 16:39 K3UK Great Charlie, JT65A very active on 20 today. 09/15 16:36 N0ZC Andy, thanks for the great JT65A guide! I'm on the air at last with it. Charlie 09/15 14:03 G0DJA /cq k3uk You there Andy? 09/15 13:27 K3UK QRV...testing Olivia on 14077 (dial). - -- Andy K3UK www.obriensweb.com (QSL via N2RJ) - For ideas on reducing your carbon footprint visit Yahoo! For Good this month.
Re: [digitalradio] QRV MT63
I copy VR10XLN, Hong Kong using RTTY on 14,077.5 Joe WB6AGR ** See what's new at http://www.aol.com
Re: [digitalradio] Re: So there I was -
Unfortunately this statement is only half true. The one thing that concerns me a great deal is that the automated stations are not listening before transmitting and at least here in the U.S. are operating illegally. And they even are open about this with comments made by the administrator of Winlink 2000, that signal detection is not practical because they would never find an open frequency. This may be based upon their experiences with the SCAMP mode that they invented that clearly demonstrated a full ability to provide busy frequency detection. But the automatic users do not want to implement these technologies.
Re: [digitalradio] Re: So there I was -
Dave When a P3 station disconnects there is an ID in P1 or CW or both. John, W0JAB At 07:18 PM 9/15/2007, you wrote: Since Pactor 3 can't be decoded with soundcard software and the SCS decoder is relatively expensive, most hams can't decode Pactor 3 messages. Thus when QRM'd by an unattended Pactor 3 station, most hams can't determine the offending callsign and so can't initiate an appropriate action.
[digitalradio] QRL ? ALE
Has anyone experimented with busy detect in PC-ALE ? I think Bonnie and others have mentioned that it does have such capability. I did notice the other day that my sounding did not activate on 40M , I wondered why but think it may have been related to the busy detect, there was a strong broadcast signal present. I wonder how much signal it takes to postpone a PC-ALE sounding? I may do some experimenting and write a QRG file with some known broadcast signals, see if it goes to sounding while a signal is present. WWV freqs might be worth a test too. -- Andy K3UK www.obriensweb.com (QSL via N2RJ)
[digitalradio] QRL? PACTOR
So, it seems that these PACTOR III modem do have the ability to busy detect before a transmission. I was told recently however (from a knowledgeable source) that the person in charge of the Winlink system refused to incorporate busy detect in to the WINLINk PBO system. Anyone know if this is true ? Can a PACTOR III modem avoid a transmission if QRG is busy BUT AIRMAIL/WInlink refuses to use it ? Andy K3UK On 9/16/07, John Becker, WØJAB [EMAIL PROTECTED] wrote: Unfortunately this statement is only half true. The one thing that concerns me a great deal is that the automated stations are not listening before transmitting and at least here in the U.S. are operating illegally. And they even are open about this with comments made by the administrator of Winlink 2000, that signal detection is not practical because they would never find an open frequency. This may be based upon their experiences with the SCAMP mode that they invented that clearly demonstrated a full ability to provide busy frequency detection. But the automatic users do not want to implement these technologies.
[digitalradio] Re: QRL ? Busy detect ALE
I tested PC-ALE on a 21 meter broadcast signal at S5 (both AM and SSB) , an S3 20M CW signal and and S5 military RTTY signal on 30M-- In each situation PC-ALE listened for a few brief seconds and then switched to transmit. Perhaps there is a setting I am missing ? Andy K3UK digitalradio@yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: Has anyone experimented with busy detect in PC-ALE ? I think Bonnie and others have mentioned that it does have such capability. I did notice the other day that my sounding did not activate on 40M , I wondered why but think it may have been related to the busy detect, there was a strong broadcast signal present. I wonder how much signal it takes to postpone a PC-ALE sounding? I may do some experimenting and write a QRG file with some known broadcast signals, see if it goes to sounding while a signal is present. WWV freqs might be worth a test too.
Re: [digitalradio] QRL? PACTOR
No ! I Don't listing to the audio on my AirMail station but I have noticed many times over the past weeks that in the lower right corner of the screen that it has said busy I can't tell you if it was other Pactor stations or other modes but I can say that it did say that the frequency was busy. The one thing that burns me is the untrue and just plain misinformation that some on this list is spreading as being the fact . John, W0JAB At 02:55 PM 9/16/2007, you wrote: So, it seems that these PACTOR III modem do have the ability to busy detect before a transmission. I was told recently however (from a knowledgeable source) that the person in charge of the Winlink system refused to incorporate busy detect in to the WINLINk PBO system. Anyone know if this is true ? Can a PACTOR III modem avoid a transmission if QRG is busy BUT AIRMAIL/WInlink refuses to use it ? Andy K3UK
Re: [digitalradio] Re: QRL ? Busy detect ALE
Hi Andy, Yes you are missing the key item with this support, its called Voice Detect, not Busy Detect! As such its looking for channel acty that is Voice or Voice like ( which is what I hate about this item) to hold off transmitting. In Amateur Radio as in most applications of ALE, you have scenarios where ALE is used in a multi-mode environment of digital signaling, digital data, digital voice and analog voice, Voice Detect looks for Analog Voice. Thus with respect to Amateur Radio it would not be used in the digital subbands but rather the Voice subbands so as not to transmit where ALE can be used in limited ways due to Amateur rules in many areas, especially here in the U.S. In MARS, and most all Government and Military operations, all modes utilized are done so on the same channels ( for the most part ) and as such Voice Detect keeps an ALE Sounding or Linking Call from stomping on an Analog Voice contact, predicated on the timing the sample period to detect the analog voice and the analog voice channel acty, which is why no form of busy channel, be it Voice Detect or other will ever be perfect unless one is looking to detect a signal that is always active, in which case the channel is for the most part useless ( unless said signal can be overcome by EIRP). I find all this channel busy detect crap rather funny myself, I know such a statement is going to bring out the flames, but intentional interference is one thing, however system automation for digital communications where one end of the equation is automated and the goal is for the Remote Attended station to grab the Automated station for access to send and receive e-mail is not interference, the stations that are operating on the same spectrum should know better, its that simple. Really what should be done at the next WARC is set aside 10, 25, 50 to 100Khz (depending on the spectrum size of each given band in question) off little used Voice spectrum on the bottom of each band that goes mostly unused except for contests of the occasional rare DX station that pops up for much more useful daily Traffic Automation Systems using 3Khz channels ( or better ) with no symbol rate limitations where no peer-to-peer contacts are NOT allowed in my opinion, there is just so much Phone spectrum going to waste its just stupid, especially consider the benefits it provided by Traffic Automation. Such a move would be a move in the right direction for the future of the Amateur Radio Service. Sincerely, /s/ Steve, N2CKH At 05:12 PM 9/16/2007, you wrote: I tested PC-ALE on a 21 meter broadcast signal at S5 (both AM and SSB) , an S3 20M CW signal and and S5 military RTTY signal on 30M-- In each situation PC-ALE listened for a few brief seconds and then switched to transmit. Perhaps there is a setting I am missing ? Andy K3UK digitalradio@yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: Has anyone experimented with busy detect in PC-ALE ? I think Bonnie and others have mentioned that it does have such capability. I did notice the other day that my sounding did not activate on 40M , I wondered why but think it may have been related to the busy detect, there was a strong broadcast signal present. I wonder how much signal it takes to postpone a PC-ALE sounding? I may do some experimenting and write a QRG file with some known broadcast signals, see if it goes to sounding while a signal is present. WWV freqs might be worth a test too. Announce your digital presence via our Interactive Sked Page at http://www.obriensweb.com/drsked/drsked.php Yahoo! Groups Links
[digitalradio] Re: QRL? PACTOR
Busy detection in my 8-year old Pactor II modem seems to be functioning fine with Winlink Classic. Perhaps it's only WL2K that is broke? Here is a portion of my recent log: 9/9/2007 9:21:18 AM 07103.30 busy with TFC PctSCS:HF 9/9/2007 1:16:19 PM 07103.30 busy with TFC PctSCS:HF 9/9/2007 1:21:20 PM 07103.30 busy with TFC PctSCS:HF 9/9/2007 6:35:19 PM 10144.00 busy with TFC PctSCS:HF 9/10/2007 8:31:19 AM07103.30 busy with TFC PctSCS:HF 9/10/2007 3:49:29 PM14107.00 busy with TFC PctSCS:HF 9/11/2007 8:15:20 AM07103.30 busy with TFC PctSCS:HF 9/11/2007 1:45:26 PM03594.00 busy with TFC PctSCS:HF 9/11/2007 3:23:54 PM14107.00 busy with TFC PctSCS:HF 9/11/2007 3:28:22 PM14107.00 busy with TFC PctSCS:HF 9/12/2007 2:40:19 PM03594.00 busy with TFC PctSCS:HF 9/13/2007 1:16:20 AM10145.00 busy with TFC PctSCS:HF 9/13/2007 8:15:19 AM07103.30 busy with TFC PctSCS:HF 9/14/2007 2:56:25 PM03594.00 busy with TFC PctSCS:HF 9/14/2007 3:00:24 PM14107.00 busy with TFC PctSCS:HF 9/14/2007 8:00:20 PM03594.00 busy with TFC PctSCS:HF 9/14/2007 8:05:25 PM03594.00 busy with TFC PctSCS:HF 9/14/2007 8:10:20 PM03594.00 busy with TFC PctSCS:HF 9/15/2007 1:00:25 AM10145.00 busy with TFC PctSCS:HF 9/15/2007 8:15:28 AM07103.30 busy with TFC PctSCS:HF ... Duane N7QDN --- In digitalradio@yahoogroups.com, Andrew O'Brien [EMAIL PROTECTED] wrote: So, it seems that these PACTOR III modem do have the ability to busy detect before a transmission. I was told recently however (from a knowledgeable source) that the person in charge of the Winlink system refused to incorporate busy detect in to the WINLINk PBO system. Anyone know if this is true ? Can a PACTOR III modem avoid a transmission if QRG is busy BUT AIRMAIL/WInlink refuses to use it ? Andy K3UK On 9/16/07, John Becker, WØJAB [EMAIL PROTECTED] wrote: Unfortunately this statement is only half true. The one thing that concerns me a great deal is that the automated stations are not listening before transmitting and at least here in the U.S. are operating illegally. And they even are open about this with comments made by the administrator of Winlink 2000, that signal detection is not practical because they would never find an open frequency. This may be based upon their experiences with the SCAMP mode that they invented that clearly demonstrated a full ability to provide busy frequency detection. But the automatic users do not want to implement these technologies.
[digitalradio] Re: Humans as Busy Detectors
First, we should put this so-called busy-channel detection in perspective: Humans are very poor busy channel detectors... whether through human error, or through ignorance, or through intention. Just try to hold a simple voice, CW, image, messaging, or texting QSO on one of the more active ham bands on any weekend will prove this fact to you beyond any doubt. Bonnie KQ6XA
Re: [digitalradio] Re: Humans as Busy Detectors
Bonnie, do you mean 27.185 mHz?
Howard K5hb
- Original Message
From: expeditionradio [EMAIL PROTECTED]
To: digitalradio@yahoogroups.com
Sent: Sunday, September 16, 2007 7:18:32 PM
Subject: [digitalradio] Re: Humans as Busy Detectors
First, we should put this so-called busy-channel detection in
perspective:
Humans are very poor busy channel detectors... whether through human
error, or through ignorance, or through intention.
Just try to hold a simple voice, CW, image, messaging, or texting QSO
on one of the more active ham bands on any weekend will prove this
fact to you beyond any doubt.
Bonnie KQ6XA
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[digitalradio] Busy Detectors
There are down sides to busy-detection: 1. There is no way to know the relative interference temperature threshold for distant co-channel users on HF. SNR at every station is different. A signal that seems in the background at one location, for one mode, may be interference to another mode working at a different SNR or a different mode at another station. 2. What to detect? How sensitive? It is possible to engineer a busy-detector that can be set for a very sensitive threshold, and detect almost any mode or almost any level. That same detector will also falsely show a busy channel most of the time on the HF ham bands. That renders the busy-detector useless for the busy-detector user who wants to have a QSO or send an important message. 3. When does the receiving station with busy-detection know whether the content of such an incoming message is an emergency? A too-sensitive busy detector might prevent such a message from being run in the first place, and the result would not be good. Thus, stations that are on the air specifically with a very likely possible purpose of running emergency traffic should probably not use a busy-detector. It is possible to envision a busy-detector that could be programmed to remotely disengage upon reception of a specific command... but such a system is not readily available at the present time, and the use of it would certainly unnecessarily complicate the sending of an emergency message at a critical time. 4. It may be counter-productive for networks or users to announce what type of busy-detection they use or don't use, because this sort of information can be used nefariously (has been and will be) by individuals on purpose to maliciously interfere or thwart normal operation. 5. We all know that there are many feuds and grudges out there on the air. It seems that certain hams who are most prone to carrying on feuds or grudge-matches may also be the same individuals who clamor most loudly for busy-detectors to be put in place by their enemy :) Bonnie KQ6XA
[digitalradio] Re: Busy detect ALE
There are several different types of busy channel detection in use by ALE systems. Some of these are hard-coded and some may be switched on/off (such as voice detection). Depending upon the ALE system, the busy detection has names like occupancy polite voice detect channel-busy and various other nomenclature. They each may have slightly different functions. Some are the same, but different names. In order to be practical, there must be a decision-making threshold through some means. That threshold may be user-selected or hard-coded. Generally speaking, some of the various ALE busy detectors work like this: 1. Detection of relative amplitude of in-band signal vs out-of-band signal. This detects the changes in audio within the occupied part of the channel (roughly 700Hz-2800Hz) and compares it, relative to the energy above and below the occupied part of the channel (roughly 200Hz-700Hz and 2800Hz-3300Hz). 2. Voice cadence detection. This uses the relative energy change repetition rate for audio voice frequencies having the majority of the energy in the peak audio voice band of the channel (roughly 400Hz-1300Hz). 3. Similar-signal detection. This detects waveforms that have similar characteristics to the desired modem. Such as sine waves, or FSK waveforms. 4. Relative amplitude threshold detection. This detects difference in instantaneous or time-weighted amplitude relative to overall amplitude. 5. Sync-detection. This detects frequency shifting in-band signals with roughly 100symbols/sec to 150 symbols/sec over some time duration interval. 6. Frequency change detection or windowing. This detects signals that vary in frequency and change over some preset time window and/or multiple frequency windows. 7. Combination detection. This uses a combination of two or more of the above methods. 8. Proprietary mystery detectors. These detectors use methods which are not entirely disclosed by the manufacturer or software designer. Some of them are quite effective and have amazingly accurate and reasonable thresholds... they are likely some type of combination detectors. Bonnie KQ6XA
Re: [digitalradio] Busy Detectors
but Bonnie, a fundamental issue has been the frustration with PACTOR just switching on mid-stream and interfering with a QSO. Other than under contesting conditions, it rarely happens with other modes. Would not it be fairly easy for programmers to build in a variable parameter that allows the user to set a signal to noise ratio and a waterfall bandwidth. If the software detects a signal above the specified SNR within the specified bandwidth, the software refused to xmit? A off setting could be used when emergencies exists. For example MixW and PC-ALE both have a pseudo way of measuring SNR. Andy. On 9/16/07, expeditionradio [EMAIL PROTECTED] wrote: There are down sides to busy-detection: 1. There is no way to know the relative interference temperature threshold for distant co-channel users on HF. SNR at every station is different. A signal that seems in the background at one location, for one mode, may be interference to another mode working at a different SNR or a different mode at another station. 2. What to detect? How sensitive? It is possible to engineer a busy-detector that can be set for a very sensitive threshold, and detect almost any mode or almost any level. That same detector will also falsely show a busy channel most of the time on the HF ham bands. That renders the busy-detector useless for the busy-detector user who wants to have a QSO or send an important message. 3. When does the receiving station with busy-detection know whether the content of such an incoming message is an emergency? A too-sensitive busy detector might prevent such a message from being run in the first place, and the result would not be good. Thus, stations that are on the air specifically with a very likely possible purpose of running emergency traffic should probably not use a busy-detector. It is possible to envision a busy-detector that could be programmed to remotely disengage upon reception of a specific command... but such a system is not readily available at the present time, and the use of it would certainly unnecessarily complicate the sending of an emergency message at a critical time. 4. It may be counter-productive for networks or users to announce what type of busy-detection they use or don't use, because this sort of information can be used nefariously (has been and will be) by individuals on purpose to maliciously interfere or thwart normal operation. 5. We all know that there are many feuds and grudges out there on the air. It seems that certain hams who are most prone to carrying on feuds or grudge-matches may also be the same individuals who clamor most loudly for busy-detectors to be put in place by their enemy :) Bonnie KQ6XA -- Andy K3UK www.obriensweb.com (QSL via N2RJ)
Re: [digitalradio] Busy Detectors
At 08:18 PM 9/16/2007, Andy, K3UK in part wrote: but Bonnie, a fundamental issue has been the frustration with PACTOR just switching on mid-stream and interfering with a QSO. If I may jump in here. Does this not go back to the so called hidden transmitter issue ?? This I think has bee beat to death by many times on this list. Find a fix for that and you will die a very rich man. But I really think a lot has to do with those that just *HATE* the wide modes (RTTY Amtor Pactor) . John, W0JAB
