[digitalradio] Re: Noise
A couple of things from experience... First, cable internet service does use HF frequencies. I forget which direction is down there, but one is. Second, your power company is a rare find these days. Ten years back it seems most truimmed the fixit guys to cut expenses. I've gone thru it with two power companies now. Time was when all power companies did just that, look for problems. If it is an insulator breaking down, for example, that's current being spent that isn't being billed to anyone. Add up enough of it and its real money to them. but wideband noise like that may not be power company related. Here at my place I've had that now for a few years, making HF pretty useless. But don't discount wall warts. Most of them now are switchers, and make lots of noise. Just not wideband constant level noise so much. And since the energy bill last year, more to come, the feds now mandate efficiency of those things. My two cents. GeorgeC W2DB
[digitalradio] SSTV
Been monitoring 14.230 all day, heard some SSB up just a bit and was W1AW using voice.. Fred VE3FAL
Re: [digitalradio] Re: Noise
It is usually so, but there are also return channels to the headend below 54 MHz in some places. A loose conector or a broken shield might allow it to leak out. 73, Jose, CO2JA -- John Taylor escribió: Ron, as a semi direct answer to your question, as a general rule cable tv frequencies typically are well above hf radio. It is not impossible for there to be interference, but generally it will be some other source. One thing to remember with most cable systems is that the line and trunk amps need to be powered and are usualy done through the cable itself with pole mounted power supplies every so often in the system. If there is a connection breakdown somewhere near you, itcould cause your symptoms. You did provide a clue to your own situation. You mentioned a bucket truck in the area when the noise suddenly stopped and then started again. If he was working at a particular pole, you might try physically walking to that pole and see if you hear any arcing, especially if this is also a power pole carrying primary voltages. It is not uncommon for the insulators to start breaking down due to dirt and grime in the air getting on the insulators and forming a path for the current to travel. This manifests itself frequently as strong intermittant static. Your noise blanker typically only works on impulse noise such as ignition, etc. Have you also eliminated all noise sources in your own home, such as televisions, computers and monitors, etc.? A great way to chase the source is to take a small portable shortwave receiver with a small antenna and follow the noise to it's source. You can usually get very close very quickly with a little leg work. Just some thoughts Best of Luck --- In digitalradio@yahoogroups.com, w4lde [EMAIL PROTECTED] wrote: If this question is inappropriate for the reflector I apologize but as of last Friday I started to experience significant noise (S-9) on all bands from 160 through 15M with the lower frequencies much stronger. I thought that it was due to power line noise but it appears to be intermittent in that it completely disappeared last Friday evening but once again showed up last Saturday and stayed this way. On the Ft1000mp the noise blankers are completely ineffective. At the same time I started having internet problems and the cable company indicated they should have the speed issue fixed by Tuesday. The cables are run on poles until they enter a subdivision which then run underground. My question is can cable lines be the possible problem to HF frequencies? The power and cable companies have been installing new poles and running new lines in the area which initially led me to believe it was a power issue however, while I was writing this email the noise completely disappeared for a few seconds and then reappeared. As I was looking out my window I noticed a cable company buck truck through the woods towards the main road, I am off now to talk to them and see what I can discover. Any suggestions? Thanks for the bandwidth if this question is inappropriate for this reflector. 73 de Ron W4LDE Announce your digital presence via our Interactive Sked Page at http://www.obriensweb.com/sked Yahoo! Groups Links -- MSc. Ing. José Angel Amador Fundora Profesor Auxiliar Departamento de Telecomunicaciones Facultad de Ing. Eléctrica, CUJAE Calle 114 # 11901 e/119 y 127 Marianao 19390 Ciudad de la Habana, Cuba Tel: (53 7) 266-3445 Mail: amador at electrica.cujae.edu.cu
Re: [digitalradio] Re: High speed packet
Going too fast on a serial port is not always a bonus. If there are errors, it is another source of retries, without even reaching the air. Go only as fast as it makes sense with very few or no errors. YMMV. Jose, CO2JA --- Bob Donnell escribió: Martin: I'd bet you were thinking of ISA instead of IDE - and probably the dual opto-SCC card developed by your countrymen back then. Ross: JNOS is probably the most actively maintained version of NET which became NOS, back in about 1990/1991 time frame. Current versions of it can be run under either Windows or Linux. JNOS has KISS as one of its historic interface methods. As long as you have a more modern serial communications chip in the computer you're using (16550-compatible) you should be able to configure it to have adequate communications with the TNC at either 57.6kbps or 115.5kbps, if the TNC supports it. The SV2AGW family of programs may also support that fast serial data rate - I don't have an easy way to check where I'm entering this email. The AGW Packet Engine (AGWPE) definitly also understands how to do KISS. My home Airmail station is using a shim to talk to AGWPE, which is talking to an AEA PK-96 using KISS, which is then interfaced with the radio. Perhaps I've not been watching the list carefully - what over-the-air data rate are you using that makes performing serial communications at 57.6kbps an advantage? Unless you're sending quite large AX.25 packets (1k or 2k) on a radio link at 38.4kbps, there's probably not much performance advantage to going that fast. And if your on-air data rate IS that fast, congratulations! 73 Bob, KD7NM -Original Message- From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of martin beekhuis Sent: Tuesday, September 09, 2008 11:38 AM To: digitalradio@yahoogroups.com Subject: [digitalradio] Re: High speed packet Hello Ross Here we have already for years running the packetnode using ax25 drivers in linux. http://sharon.esrac.ele.tue.nl (sorry in dutch) Different speed up to 76800 however we use SCC IDE controlers I think via the serial port ttyS0 ax0 will do also. Before we switched from DOS-6.11 to linux we used NOS or NET No GUI all very basic but reliable from 1987 till now 73 matin pa3dsc I am looking for a packet program, which I can use to operate my Symek TNC3S at 57600 but which has the kiss mode. Any one any ideas. Packet was in favour a few years ago and all the programs I can find are very old, dont like the kiss mode, or cant talk to the TNC3S at 57600. Regards to all Ross ZL1WN . Announce your digital presence via our Interactive Sked Page at http://www.obriensweb.com/sked Yahoo! Groups Links Announce your digital presence via our Interactive Sked Page at http://www.obriensweb.com/sked Yahoo! Groups Links -- MSc. Ing. José Angel Amador Fundora Profesor Auxiliar Departamento de Telecomunicaciones Facultad de Ing. Eléctrica, CUJAE Calle 114 # 11901 e/119 y 127 Marianao 19390 Ciudad de la Habana, Cuba Tel: (53 7) 266-3445 Mail: amador at electrica.cujae.edu.cu
