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Date: Fri, 18 Feb 94 04:30:02 PST From: Info-Hams Mailing List and Newsgroup <info-hams@ucsd.edu> Errors-To: Info-Hams-Errors@UCSD.Edu Reply-To: Info-Hams@UCSD.Edu Precedence: Bulk Subject: Info-Hams Digest V94 #174 To: Info-Hams Info-Hams Digest Fri, 18 Feb 94 Volume 94 : Issue 174 Today's Topics: ARRL Letter available via FTP Base Station Power Supply DJ-580 UHF receive ragne Foot race across desert? FT-530 Firmware Problems (epilogue) Golf Causes Cancer! Help wanted Iambic keyer paddles Keyboards at testing sessions QSL info for Cuba Send Replies or notes for publication to: <Info-Hams@UCSD.Edu> Send subscription requests to: <Info-Hams-REQUEST@UCSD.Edu> 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: Thu, 17 Feb 1994 13:57:05 GMT From: ucsnews!sol.ctr.columbia.edu!howland.reston.ans.net!europa.eng.gtefsd.com!library.ucla.edu!csulb.edu!csus.edu!netcom.com!marcbg@network.ucsd.edu Subject: ARRL Letter available via FTP To: info-hams@ucsd.edu As part of an experiment, I am making the ARRL letter, which I have been posting to this and rec.radio.info, available via anonymous FTP. I plan to keep a repository of ARRL letters (we'll see how it goes). Future plans also are for the W5YI letter. If this proves to work without too much hassle, I'll keep it up. ftp to: netcom8.netcom.com /pub/marcbg Enjoy! -- ================================================ Marc B. Grant Voice Mail: 214-246-1150 marcbg@netcom.com Amateur Radio N5MEI marcbg@esy.com ================================================ ------------------------------ Date: Thu, 17 Feb 94 00:35:15 GMT From: pacbell.com!amdahl!netcomsv!netcomsv!vitsemi!rob@network.ucsd.edu Subject: Base Station Power Supply To: info-hams@ucsd.edu One of my current projects is to set up a base station for VHF/UHF using a mobile rig. This means I need a 13.8V power supply that can supply up to 12 Amperes. I know the supply should not have too much ripple, but I do not know how much is acceptable. Initially, I was planning on building/purchasing a 12V/14A supply. But now I am considering using a deep discharge marine lead-acid battery that is continuously charged for my power supply. Are there any safety issues associated with keeping this type of battery on continuous charge? Using such a battery has the advantage of being a good emergency backup. The batteries cost much less than power supplies, so if the charger is inexpensive, the cost will be about the same. The 1993 ARRL Radio Amateurs Handbook has a circuit for a 12V charger. It appears to be suitable for my needs. It appears to be intended to be used as a charging circuit, but not while the battery is in use. Is it suitable for continuous operation? I would expect that the battery would keep ripple quite low. In addition, I would rather not make my own PC board. The Handbook does not give a source for the PC boards. Does anyone have any PC boards for this available? Advice and suggestions for this project are welcome. -- ------------------------------------------------------------- Rob Eccles KD6VYW | Disclaimer: The statements made here rob@vitsemi.com | do not represent my employer. "Hope for the best, but prepare for the worst." -unknown ------------------------------ Date: 17 Feb 1994 23:23:33 GMT From: olivea!koriel!news2me.EBay.Sun.COM!jethro.Corp.Sun.COM!maverick!ruentien@uunet.uu.net Subject: DJ-580 UHF receive ragne To: info-hams@ucsd.edu hi, guys: I recently purchase a ALINCO DJ-580, it is a great radio. The quality of audio is great. I have no complaint about this rig. I got one question here, the menu stated the receive range for UHF is from 430 to 470 Mhz, but what I found is that I can make it from 400 to 520 Mhz. I didn't make any modification on this rig, I don't know this is misinformed on menu? or ..... Any answer will be appreciated!! PS. I don't have call-sign yet, just pass the test last week. ------------------------------ Date: Thu, 17 Feb 1994 15:23:37 GMT From: swrinde!cs.utexas.edu!howland.reston.ans.net!math.ohio-state.edu!news.acns.nwu.edu!raven.alaska.edu!aurora.alaska.edu!nsmca@network.ucsd.edu Subject: Foot race across desert? To: info-hams@ucsd.edu In article <2johsr$r45@garuda.csulb.edu>, byon@beach.csulb.edu (Byon Garrabrant) writes: > In article <jfhCL86vF.tv@netcom.com>, Jack Hamilton <jfh@netcom.com> wrote: >>I remember hearing about a foot race somewhere across the desert in >>Southern California and maybe Nevada. It's run by a police agency as >>a fundraiser for some charity, I think. They have solicited amateur radio >>volunteers in the past, but I heard about it only after the event (and I >>don't remember where). >> >>Does anyone have more information about this event? >> > > > It is called the Challange Cup Relay Race - also know as the Baker to Vegas > race. It's a 120 mile relay race in 20 legs from Baker, in California, > through Pahrumph (sp) and on into Vegas. This year it will be held > on April 8-9. We (Orange County RACES) set up a communications system > for the use of a few county teams. It is an international event, run > by police officers. This is all off the top of my head, so I may be off > a bit, but I gan get you as much info as you would like. > > -- > Byon Garrabrant KD6BCH byon@csulb.edu > There is one in Alaska or was one, between I believe Fairbanks and Anchorage or was it Fairbanks and Valdez. It used to be run, but not sure if its doen any more.. It was run by mostly State Troopers, APD (Anchorage PD), and other Alaskan Police/Law Officers.. Anyone have any info? === Ghost Wheel - nsmca@acad3.alaska.edu also 1@9714 WWIVnet.. ------------------------------ Date: 17 Feb 1994 08:52:39 -0800 From: swrinde!cs.utexas.edu!howland.reston.ans.net!europa.eng.gtefsd.com!library.ucla.edu!csulb.edu!nic-nac.CSU.net!ctp.org!not-for-mail@network.ucsd.edu Subject: FT-530 Firmware Problems (epilogue) To: info-hams@ucsd.edu RGS@gfimda.UUCP (Robert G. Schaffrath) writes: > This is a post of an item I deposited on Compu$erve's HAMNET forum: > > Well I just received my re-repaired FT-530 back today. As I had promised > earlier, here is the finally summary of what was done and the cost if it > is out of warranty. Please note that my radio is Lot #16. All FT-530's > that I have played with suffer from the DTMF code squelch problem: More questions: I got my 530 around 5 or 6 months ago. How long is the warranty good for? I have never tried using the DTMF code squelch. Is this something I should send my radio back for even though I have never tried it out?? If I have performed the jumper 13 removal, will that invalidate the warranty?? Steve Adams sadams@ctp.org ------------------------------ Date: Tue, 15 Feb 1994 16:00:28 GMT From: microsoft!wingnut!edmitch@uunet.uu.net Subject: Golf Causes Cancer! To: info-hams@ucsd.edu I used to be a general aviation pilot. As a pilot, I learned very quickly that there are three things you can find near the end of any runway: 1) A high tension power line, obstructing the approach course, 2) The local sewage treatment plant, 3) and the municipal golf course. I wonder if there is a connection between golf courses, power lines and sewage treatment plants! Maybe this explains an increase in the cancer death rates of golf course managers. Then too, maybe they all smoke cigarettes. Then again, this is all so much conjecture, usually about large percentile differences in very tiny numbers. Ed Mitchell KF7VY@N7FSP.WA.USA edmitch@aol.com edmitch@microsoft.com "The opinions expressed are my own and not necessarily those of my employer." ------------------------------ Date: 17 Feb 94 12:32:46 GMT From: olivea!sgigate.sgi.com!sgiblab!swrinde!cs.utexas.edu!howland.reston.ans.net!pipex!uknet!comlab.ox.ac.uk!oxuniv!laczik@decwrl.dec.com Subject: Help wanted To: info-hams@ucsd.edu Hi, I am thinking about getting a Kenwood TS-440S or a Yaesu FT-757GX. I would be most interested to hear about your experience with either of them, or even better a comparison between the two. Also: any alternative suggestions, e.g. how inferior would a TS-140S or FT-747GX would be? My main requirement is good RX performance and I also need a computer interface to store VFO and mode data, and for the remote control of as many functions as possible. Many thanks, John ------------------------------ Date: Thu, 17 Feb 1994 13:16:06 GMT From: agate!howland.reston.ans.net!news.intercon.com!udel!news.sprintlink.net!nic.hookup.net!hookup!ukma!rsg1.er.usgs.gov!junger@ames.arpa Subject: Iambic keyer paddles To: info-hams@ucsd.edu >I am told that in general, right handed operators use the right paddle >for the dash while the left paddle is used for the dit. OK no problem >so far. > >Is there a rationale behind this convention? > I am left-handed and use a single paddle key set up so that my thumb does dashes. This habit probably originates from my use of right-handed bugs back in the 50's and 60's. It does allow me to use any right-handed ham's keyer without any problems, though. 73's -- John W3GOI ------------------------------ Date: Thu, 17 Feb 1994 14:40:29 GMT From: swrinde!emory!wa4mei.ping.com!ke4zv!gary@network.ucsd.edu Subject: Keyboards at testing sessions To: info-hams@ucsd.edu In article <2970520692.0.p01258@psilink.com> TJA@Panix.Com writes: >> >>Would the VEC's kick me out if I brought a laptop to a code test session or >>should I wait until my paper speed catches up to my keyboard speed? > > I run the VE sessions for our local club here in Stamford, CT >and using a laptop is perfectly fine in a word processor or editor mode. >You may just have to show it to them first. If they give you are hard time >just fly out here and we'll let you use one! Or bring in your Royal or Smith Corona portable typewriter. Even the FCC allowed you to copy by mill back in the 1960s. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Thu, 17 Feb 1994 15:59:42 GMT From: ucsnews!sol.ctr.columbia.edu!math.ohio-state.edu!cs.utexas.edu!swrinde!sgiblab!pacbell.com!sjhawk2@network.ucsd.edu Subject: QSL info for Cuba To: info-hams@ucsd.edu Hello, I would like to know what the best way to QSL to CUBA is? If anyone has the lastest info please Email me. Thanks Steve WV6U ------------------------------ Date: Thu, 17 Feb 1994 15:27:28 GMT From: swrinde!emory!wa4mei.ping.com!ke4zv!gary@network.ucsd.edu To: info-hams@ucsd.edu References <1994Feb14.131000.8706@arrl.org>, <1994Feb15.160936.23577@ke4zv.atl.ga.us>, <1994Feb16.173115.8288@arrl.org> Reply-To : gary@ke4zv.atl.ga.us (Gary Coffman) Subject : Re: Medium range point-to-point digital links In article <1994Feb16.173115.8288@arrl.org> jbloom@arrl.org (Jon Bloom (KE3Z)) writes: > >To talk about a "power dB" as separate from a "voltage dB" is >meaningless, *unless* the two voltages you are comparing occur across >different impedances, which is not the case here. Your statement makes >no sense. Yep. I can only plead brain fade on that one. You're exactly correct. 20log(voltage ratio) is exactly the same thing as 10log(power ratio). It's the power ratio we hear, but it's the voltage ratio we're looking at in the A/D-D/A conversions. (Actual devices are current driven, but it amounts to the same thing.) >So, what's enough SNR, 50 dB or 100 dB? I suggest it's 50 dB. A >compact disk gives you about 90 dB, and I'd hate to think we need >better than CD quality on our voice links! I agree. We strive to achieve CD quality in our broadcast transmission systems, but we rarely achieve it. We count on the 62 db spl of a quiet room to mask the defects in transmission on the lower end. Since 110 db spl is threshold of pain, we only *have* to deliver about 48 db SNR to satisfy the listener. People using good tight sealing headphones can hear the noise, but otherwise it's lost in the ambient room noise. Note that for amateur use, our source is a live mike in an often less than quiet room. So there's no reason to have greater than 48 db SNR in our transmission system since the source SNR will be no better than that. >Of course, to realize the 50-dB SNR from the 8-bit system, the signals >have to use all of the available signal range. If you use less, the >SNR is reduced proportionally, as the signal is closer to the noise >floor. That probably argues for something on the order of a 12-bit >converter for "overhead." But with good ALC ahead of the A/D, 8 bits >might be acceptable. ALC often makes the problems worse if implemented improperly. What we want is enough gain to put the source noise at the floor of the converter, and a gain *reduction* circuit to ride peaks so that we stay in the converter's range. That'll minimize our system noise. If the source has a SNR greater than 50 db, 8 bits will compress it down to 50 db. If the source SNR is worse than 50 db, we can't make it better by scaling gain in front of the A/D. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Thu, 17 Feb 1994 12:28:00 GMT From: pacbell.com!att-out!cbnewst!kt2q@network.ucsd.edu To: info-hams@ucsd.edu References <1994Feb11.001239.2842@ke4zv.atl.ga.us>, <CL1p2x.8s2@news.Hawaii.Edu>, <CL5EDr.3CB@news.Hawaii.Edu> Subject : Re: Whats it got to do with 40 m QRP? Looks to me like this thread should be renamed "Copying whole words on CW" Seems like it has nothing to do with cw QRP. All you have to do is edit the subject line in your followup.... Rick KT2Q ------------------------------ Date: Thu, 17 Feb 1994 14:31:14 GMT From: library.ucla.edu!europa.eng.gtefsd.com!emory!wa4mei.ping.com!ke4zv!gary@network.ucsd.edu To: info-hams@ucsd.edu References <01H8X21VF1N6ECXSL5@tntech.edu>, <CLAz5v.Iss@news.direct.net>, <fred-mckenzie-160294172009@k4dii.ksc.nasa.gov> Reply-To : gary@ke4zv.atl.ga.us (Gary Coffman) Subject : Re: John Ramsey In article <fred-mckenzie-160294172009@k4dii.ksc.nasa.gov> fred-mckenzie@ksc.nasa.gov (Fred McKenzie) writes: >In article <CLAz5v.Iss@news.direct.net>, kg7bk@indirect.com (Cecil Moore) >wrote: >> John Ramsey and I have never met in person. We have exchanged letters and >> e-mail and I perceive him to be a friendly, helpful, and assertive >> businessman who is trying to make a living at his hobby. > >Cecil- > >Over the years, I have seen John at his booth at several hamfests. He may >even be at the Orlando Hamfest this coming weekend, if you happen to be in >the Central Florida area. > >My impression is as yours, that he is a reputable person. While his >products are not in the Kenwood or Icom category, neither are his prices. >I have a nice solid-state, dual trace, 20 MHz oscilloscope, purchased from >him several years ago. Except for the nameplate, it is identical to one >sold by several other companies. However, the other companies charged a >LOT more for theirs! Actually his pricing was about in line with other resellers of Goldstar scopes, and you can get a very much better used Tek 453A for less money. It's not a ripoff, but it's not that much of a bargain either, even though he cut the price and threw in a digital meter when I bought one from him. >I think the kits he sells are aimed towards people like ourselves, who are >quite willing to go through the ordeal of de-bugging a kit, for the feeling >of accomplishment from getting it to work! Unfortunately, we are like >dinosaurs about to become extinct. > >The modern ham seems to think a kit is something you merely plug the parts >into, like assembling an IBM-clone computer from modules. From that point >of view, I'll admit that John's kits are not "modern". Well I wouldn't object if the kits were marketed as random collections of out of spec parts for a poor design that, if you follow the assembly instructions exactly, won't meet FCC spectral purity requirements, or Ramsey advertised sensitivity, selectivity, and power output specs. Sure you can replace parts, extensively modify the design, and alter tuneup procedures so that the end product is usable and legal, but only if you have a spectrum analyzer and a bench full of other equipment, as well as a good deal of RF experience. Or if you don't care that you're spraying RF over half the band and keying half a dozen repeaters at once. If the kit were advertised as a *starting point* for an experienced builder to develop his own transceiver design, I don't think there'd be much complaint. But as it stands, it's cheaper, and better, to start with a piece of surplus gear that at least met FCC specs at one time, and modify *that* to the amateur band. At least you know up front what you're getting into. Perhaps hams have been spoiled by the good repeatable designs of other kit suppliers such as the defunct Heathkit, or the current kits available from Down East Microwave and some others, where, if you follow instructions, you'll get a finished product that, if not exactly high performance, at least meets published specs and FCC requirements without need of sophisticated test equipment and extensive experience. There's really no excuse for a design that allows transmission with an unlocked synthesizer. Nor is there an excuse for a PA design that emits a spectrum that looks like a comb except at one razor sharp tuning point. Proper unconditionally stable amplifiers with fixed component filtering are too easy to design to tolerate the Ramsey approach of critically tweaked circuits any longer. Note that I had fun discovering what was wrong with the design and engineering fixes for it once I realized that there were serious problems. But I don't think most builders would test their transceiver with a lab grade spectrum analyzer and realize it had serious problems that needed fixing. For the ham whose bench only contains a soldering iron, DVM, and maybe a commercial transceiver, noticing that the Ramsey kit was grossly out of compliance with FCC requirements wouldn't be obvious. They'd likely go ahead and use it until a determined band of T-hunters found them and pinned their coax. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Thu, 17 Feb 1994 14:50:55 GMT From: swrinde!emory!wa4mei.ping.com!ke4zv!gary@network.ucsd.edu To: info-hams@ucsd.edu References <2jqi1t$rer@pegasus.cc.ucf.edu>, <2jt93e$ds9@charm.magnus.acs.ohio-state.edu>, <CLC4Dw.10E@oakhill.sps.mot.com> Reply-To : gary@ke4zv.atl.ga.us (Gary Coffman) Subject : Re: Nude amateur radio clubs In article <CLC4Dw.10E@oakhill.sps.mot.com> ben@yosemite.sps.mot.com (Ben Thornton) writes: >In article <2jt93e$ds9@charm.magnus.acs.ohio-state.edu>, >> >>Even the *thought* of receiving a QSL card with a nude picture of the average >>ham on it is enough to offend me. I mean, seriously, folks. Leaf through >>any QST of recent (or even ancient) vintage, look at the pictures of the >>hams and imagine seeing them nude. > >So, explain to me just how it is that someone is somehow a different person >simply because they wear no clothing. The difference is only in the eye >of the beholder... Of course, all esthetics are in the eye of the beholder. Aside from it's utilitarian aspect, decorative clothing is designed to mask the ugly, not hide the beautiful. And according to the prevailing esthetic, most hams *need* that decorative covering to avoid offending the eye of the beholder. A prime rule of society is that one shouldn't do something in public that frightens the horses. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ End of Info-Hams Digest V94 #174 ****************************** ******************************