From wang!elf.wang.com!ucsd.edu!info-hams-relay Mon Apr 1 18:00:25 1991 remote from tosspot Received: by tosspot (1.64/waf) via UUCP; Mon, 01 Apr 91 21:01:19 EST for lee Received: from somewhere by elf.wang.com id aa22842; Mon, 1 Apr 91 18:00:24 GMT Received: from ucsd.edu by relay1.UU.NET with SMTP (5.61/UUNET-shadow-mx) id AA10274; Mon, 1 Apr 91 10:18:57 -0500 Received: by ucsd.edu; id AA04458 sendmail 5.64/UCSD-2.1-sun Mon, 1 Apr 91 04:30:32 -0800 for brian Received: by ucsd.edu; id AA04453 sendmail 5.64/UCSD-2.1-sun Mon, 1 Apr 91 04:30:29 -0800 for /usr/lib/sendmail -oc -odb -oQ/var/spool/lqueue -oi -finfo-hams-relay info-hams-list Message-Id: <9104011230.AA04453@ucsd.edu> Date: Mon, 1 Apr 91 04:30:27 PST From: Info-Hams Mailing List and Newsgroup Reply-To: Info-Hams@ucsd.edu Subject: Info-Hams Digest V91 #256 To: Info-Hams@ucsd.edu Info-Hams Digest Mon, 1 Apr 91 Volume 91 : Issue 256 Today's Topics: ARRL BULLETIN 17 ARLB017 ATV: AM or FM DX BULLETIN 15 ARLD015 Looking for info on a specific freq. band N8EMR_BBS_INFO SPECIAL BULLETIN 6 ARLX006 Send Replies or notes for publication to: Send subscription requests to: Problems you can't solve otherwise to brian@ucsd.edu. Archives of past issues of the Info-Hams Digest are available (by FTP only) from UCSD.Edu in directory "mailarchives/info-hams". We trust that readers are intelligent enough to realize that all text herein consists of personal comments and does not represent the official policies or positions of any party. Your mileage may vary. So there. ---------------------------------------------------------------------- Date: 1 Apr 91 06:01:23 GMT From: swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!tut.cis.ohio-state.edu!n8emr!@ucsd.edu Subject: ARRL BULLETIN 17 ARLB017 To: info-hams@ucsd.edu ============================================================== | Automatic relayed from packet radio via | | N8EMR's Ham BBS, 614-895-2553 1200/2400/9600/V.32/PEP/MNP5 | ============================================================== ZCZC AG82 QST DE W1AW ARRL BULLETIN 17 ARLB017 FROM ARRL HEADQUARTERS NEWINGTON CT MARCH 29, 1991 RELAYED BY KB8NW/OBS & BARF-80 BBS TO ALL RADIO AMATEURS Effective April 1, 1991 W1AW voice bulletins will be coming on the air 15 minutes later. Look for the phone bulletins to start at 45 minutes past the hour rather than on the half hour. This change allows more time for the transmission of bulletins on digital modes. ------------------------------ Date: 31 Mar 91 17:47:26 GMT From: usc!rpi!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv!gary@ucsd.edu Subject: ATV: AM or FM To: info-hams@ucsd.edu In article <1991Mar29.005013.29370@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu (Phil Howard KA9WGN) writes: >Some of the ATV equipment on the market for 23cm uses FM instead of AM or >VSB as its modulation. > >I'd like to know what the merits in doing this are. I note that the ARRL >bandplan for 23cm includes 5 "channels" for ATV that are only 6 MHz wide. > >One maker of FM equipment tells me that the picture is a lot less noisy >and the bandwidth is the same as AM. I don't see how the picture can be >a lot less noisy. FM gets its advantages when the deviation is high enough >that noise will not (at a detectable level) modulate the phase of the >carrier since the amplitude is constant after limiting. Once the "FM improvement" threshold is passed, FM is the big winner. For example, on satellite TV, all satellite TV is FM, a C/N ratio of 10 db yields a 42 db signal to noise ratio in the picture. This is considered "broadcast quality". Hint: We rebroadcast our network signal from a satellite distribution system with a C/N of about 10 db on rainy days. When it's not raining we get a C/N of 40 db, but the signal to noise ratio of the picture only improves to 50 db. So, once the threshold is passed there is little improvement in the picture for huge increases in signal strength. As a point of reference, most broadcast videotape recorders only achieve a 40 to 50 db signal to noise ratio. >Broadcast FM uses a deviation (peak) of 75 kHz for a signal bandpass that >is 15 kHz. I don't know how pre-emphasis actually affects this. The spacing >between stations in the same area is 800 kHz. I take this latter number to >mean that at 400 kHz from the carrier center, the sidebands are weak enough, >but still important enough, that sidebands from an equal level (or maybe >just a little stronger?) signal 800 kHz away can affect the signal. This >might be the point where filtering in the IF should cut off? No. These limits were set by the FCC so that really cheap receivers would work reliably. By law an FM station cannot radiate any sidebands outside it's 200 khz channel assignment. In the case of satellite TV, the normal transponder channel is 30 Mhz wide. Increasingly we are using "half transponder" modulation of 15 Mhz so that the other half of the transponder can be used for *another* TV signal. So deviation ratios of 3 are quite usable with FM TV. If you can tolerate a little degradation of the picture, a deviation ratio of one should be practical. >Another aspect of FM that bothers me a lot is the fact that, as the signal >gets weaker and weaker, the quality of the resultant signal drops even >faster. The point at which AM and FM equal out will probably be a noisy >picture, but below that, FM declines very rapidly. Using techniques such >as frame averaging on the demodulated video won't work, and applying such >averaging to the IF before demodulation cannot work because the signal is >not a truly coherent one, and may never be over some paths. With AM, there >is at least a reasonable hope of using frame averaging if you have enough >signal to syncronize to, or another means of syncronizing. One of the things Once you drop below the FM threshold, the signal does degrade very rapidly. But get just a little above the threshold and the picture gets about as good as it can get. Also, modern phase locked loop detectors can really dig down in the noise. Usable broadcast pictures can be had with a C/N of only 3 db. With a good receiver such as the Harris you'd have a 30 db picture signal to noise ratio with a 3 db C/N, that's good enough for a news live shot. I'd like to see usable AM pictures that weak. By the way, all these TV news remote trucks you see scurrying about use FM microwave links too. Our trucks use 10 watt transmitters in the 2 Ghz range and we get routine link range of at least 50 miles. The trucks use 50 foot pneumatic masts mounting 14 db gain circular polarized antennas. Note that the 10 watt signal has to travel through about 60 feet of RG9 to reach the antenna. That's about 12 db loss at 2 Ghz. One final note, I don't know of *any* network affiliate that genlocks his plant to the network signal these days. In the case of NBC affiliates, the network downlink unit contains a frame syncronizer that is referenced to the station's master sync generator. All signals from the plant including the network signal are referenced to that cheap little crystal oscillator. With frame syncronizers cheaper than a decent sync generator these days, most plants have at least a half a dozen syncronizers for retiming incoming feeds from their network, their remote trucks, their helicopters, and any satellite feeds they may be using for their newscast. Nobody would consider genlocking his plant to the unstable signal coming from a news chopper, yet the news producer wants that chopper picture chroma keyed in a window with his on set talent. He also wants to lay fancy news graphic supers over the picture. The frame syncronizer comes to the rescue. Most frame syncronizers will freeze the last good frame they receive until another good one comes along. A recent article about using TV signals to achieve an atomic clock accuracy reference that appeared in 73 Magazine really made me laugh. I doubt that there is a broadcaster left in the country that doesn't pass his network signal through a frame syncronizer when it enters his plant. Thus your "atomic clock" reference is really a crystal oscillator that probably isn't even in an oven. Indeed the NBC network routinely does live satellite switches inside their programming. From one frame to the next your picture may be coming from the East coast or the West coast. They count on the frame syncronizer in the local affiliate plants to keep the picture from rolling on your set at home. Gary KE4ZV ------------------------------ Date: 1 Apr 91 06:01:47 GMT From: swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!tut.cis.ohio-state.edu!n8emr!@ucsd.edu Subject: DX BULLETIN 15 ARLD015 To: info-hams@ucsd.edu ============================================================== | Automatic relayed from packet radio via | | N8EMR's Ham BBS, 614-895-2553 1200/2400/9600/V.32/PEP/MNP5 | ============================================================== ZCZC AG82 QST DE W1AW DX BULLETIN 15 ARLD015 FROM ARRL HEADQUARTERS NEWINGTON CT MARCH 29, 1991 RELAYED BY KB8NW/OBS & BARF-80 BBS TO ALL RADIO AMATEURS Thanks to Bob Dow, WB2CJL, with the Western New York DX Association and Paul, KB1BE, with the Connecticut DX Association for the following DX information. FROM THE DXCC DESK. The documentation for the recent ET2A operation has been received and accepted by DXCC. QSL cards will be accepted as soon as they are received. BANGLADESH, S2. Jim Smith, VK9NS, is NOT operating as S21U. The station found on 21255 KHz at 1730 UTC and working Europe was not Jim according to Kirsti, VK9NL. Hopefully, Jim will be on Saturday or Monday if he receives his official license, according to the latest FAX from Kirsti. KAMPUCHEA, XU. Boo and Phet, XU1DK, are now active on RTTY. Look for them on 21088 KHz around 1300 to 1400 UTC. They have no commercial power at their site and have been using power from an old generator that is working at night local XU time. Their typing maybe slow, but they will QSO with USA stations when conditions permit. There is no postal system in XU land so log info must be passed by hand to get to Japan. QSL cards will be slow, so please be patient. QSL to PO Box 80, KOUJIMACHI, Tokyo, Japan. Do not send cards to TORU, JG1RVN. MARIANA ISLANDS (SAIPAN), KH0. Look for JA1PGY. During his vacation, he will be operating from Saipan as KH0/JA1PGY. He will be QRV around April 26 to 28. He will have RTTY capability and will be operating with a Zepp halfwave antenna. WARC band operations will be attemped. BAHRAIN, A9. Rich, KI3V, keeps the DX crowd busy with his operation on CW and SSB on all bands. He will be there for two more weeks. QSL via his home call. ST. PAUL ISLAND, CY9. QSL cards for the CY9CF operation are still in the hands of the printers. They will be shipped to FP5DX, around the first week in April. BHUTAN, A51. Jim, VK9NS, and Kirsti, VK9NL are still planning to go to Bhutan in early May for two weeks. Equipment will be shipped earlier as they will bring a beam plus a linear amplifier. NEPAL, 9N1. 9N1MM has been heard and worked in Western New York on 20 meter cw. YEMEN, 7O1. Gabi, DL2BCH, now has the computer disks containing the logs for the 7O1AA operation. It will take a few days to change the computer format and then the cards will be answered. NOTE 1. WB2WOW, QSL manager for ET2A and ST0DX became a silent key on Saturday, March 23. QSL to the same address as cards will be handled by Howard, WA2NHA. Good Luck on DX de KB8NW/OBS ------------------------------ Date: 1 Apr 91 08:30:24 GMT From: sdd.hp.com!usc!neuro.usc.edu!demikhov@ucsd.edu Subject: Looking for info on a specific freq. band To: info-hams@ucsd.edu In article <2412@stsci.EDU> tullos@stsci.EDU (Calvin Tullos) writes: >I'm looking for information on who might be broadcasting >between 174 MHZ and 199 MHZ..... vs. wireless microphone. 174-216 MHz Television Channels 7-13 (6 Mhz of spectrum for each channel) ------------------------------ Date: 1 Apr 91 06:00:47 GMT From: swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!tut.cis.ohio-state.edu!n8emr!root@ucsd.edu Subject: N8EMR_BBS_INFO To: info-hams@ucsd.edu The N8EMR Ham bbs is online to serve the needs of the amateur radio operators.. 1/26/91 The BBS is now running on the 386 machine. 12/5/90 Columbus and HBBS are now available via PC pursuit dialout. 7/15/90: This BBS is now part of the AMSAT BBS network.. HOW TO ACCESS THE N8EMR HAM RADIO TELEPHONE BBS !!! System Name: N8EMR Phone: 614-895-2553 Login: hbbs Data Settings: 8 Bits, NO Parity, 1 Stop Bit Times: 24hrs IP Address: 44.70.0.1 Amateur radio annonymous ftp access is available via the ohio netrom/ip network. CMHIP is the Netrom node Id and is known by most of the nodes in ohio. (its slow but it works) This is only via the ohio packet network. This sytem is not available via the "INTERNET". To access the system via the dialup, at the login prompt type hbbs (lower case only), you will then enter the BBS program. Follow the directions from the bbs prompts. I attempt to keep the latest and greatest HAM software on-line, and encourage all to upload Here is some of software that is available for downloading. KA9Q TCP/IP Software for various computers, PC,atari-st,Mac, amgia, unix MORSE CODE Tutors Modifications for HAM Rigs and Scanners DX and contesting programs Various amateur Newsletters Packet Terminal programs AMSAT news and satellite keplerian elements Files and messages areas for AMSAT, GENERAL topics, PACKET, KA9Q, MODS to various rigs, TVRO,SCANNER and SWL. Many mb of of file of interest to the radio operator. Question or comments to Gary W. Sanders (gws@n8emr or ...!osu-cis!n8emr!gws), 72277,1325 N8EMR @ W8CQK (ip addr) 44.70.0.1 [Ohio AMPR address coordinator] HAM BBS (1200/2400/9600/V.32/PEP/MNP=L5) 614-895-2553 Voice: 614-895-2552 (eves/weekends) ------------------------------ Date: 1 Apr 91 06:01:26 GMT From: swrinde!zaphod.mps.ohio-state.edu!tut.cis.ohio-state.edu!n8emr!@ucsd.edu Subject: SPECIAL BULLETIN 6 ARLX006 To: info-hams@ucsd.edu ============================================================== | Automatic relayed from packet radio via | | N8EMR's Ham BBS, 614-895-2553 1200/2400/9600/V.32/PEP/MNP5 | ============================================================== ZCZC AX28 QST DE W1AW SPECIAL BULLETIN 6 ARLX006 FROM ARRL HEADQUARTERS NEWINGTON CT MARCH 28, 1991 RELAYED BY KB8NW/OBS & BARF-80 BBS TO ALL RADIO AMATEURS NASA has announced that the all ham crew of STS-37 will fly aboard Atlantis on April 5 at 1418 UTC. The packet callsign to be used is KB5AWP, transmitting on 145.51 MHz. Ground stations transmit on 144.91. Transmit only when the shuttle is in your range. Listen for bulletins concerning random voice and SSTV times from the Goddard ARC, WA3NAN, on 3860, 7185, 14295 and 21395 KHz. ------------------------------ Date: 1 Apr 91 05:52:04 GMT From: suns.UMD.EDU!jph@umd5.umd.edu To: info-hams@ucsd.edu References <9103192122.AA01566@ucsd.edu>, , <1991Mar31.223819.22840@usenet.ins.cwru.edu> Reply-To : jph@suns.UMD.EDU Subject : Re: First No-code Tech? In article <1991Mar31.223819.22840@usenet.ins.cwru.edu> rab@hal.CWRU.Edu (Roger Bielefeld) writes: >K1MAN just broadcast a report that the first no-code tech license >was issued to Robert Williams of Annapolis, Maryland. He was issued >the call N3IFY. > >Roger N8NNK/AE >-- >Roger Bielefeld Case Western Reserve University >rab@hal.cwru.edu Cleveland, Ohio USA Well, I got mine in the mail over a week ago. It is dated 19 March '91. The FCC was faster than I expected. (I took the test 16 Feb 91.) We're already out there. Pat Harrington N3IZV ------------------------------ End of Info-Hams Digest ******************************