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- INFO-HAMS Digest Wed, 8 Nov 89 Volume 89 : Issue 855
-
- Today's Topics:
- Contest log program?
- ftp access for mods database
- How to use the incoming QSL bureau?
- ICOM IC-740
- QSLs and SASEs (2 msgs)
- Tuning dipoles and antennas.
- ----------------------------------------------------------------------
-
- Date: 7 Nov 89 13:17:49 GMT
- From: att!cbnewsj!k2ph@ucbvax.Berkeley.EDU (The QRPer)
- Subject: Contest log program?
-
- >From article <1250@marlin.NOSC.MIL>, by price@marlin.NOSC.MIL (James N. Price):
- > In article <30500273@ux1.cso.uiuc.edu> phil@ux1.cso.uiuc.edu writes:
- >>
- >>I would be interested in seeing or hearing about contest logging programs
- >>that are available as freeware or shareware, with sources.
- >
- > So would I, especially one that's geared for Sweepstakes.
- >
- > And I'd even be willing to PAY (heaven forbid) a nominal amount
- > for a program if it's good (i.e. the non-DX equivalent to the K1EA
- > program for CQWW, ARRL Test, etc).
- >
- > --Jim, K6ZH
-
- Dave, K8CC, has a program similar to K1EA's software except that it
- supports North American Sprint, ARRL Sweepstakes, and (I think) IARU
- HF Champsionship. Dave tried to make the human interface as nearly
- similar to K1EA as he could and I'd say he's been about 90 per cent
- successful in that regard. Like K1EA, you can key your radio from
- the serial port, although unlike K1EA, you can't key it from the
- parallel port. However, K8CC's software enables you to key a digital
- voice keyer from the parallel port, assuming you have a DVK to key.
-
- Dave has said he will make his program available to anybody who wants
- it. I simply sent him a 5.25 inch formatted floppy with a stamped
- self-addressed mailer and he had it back to me in about two weeks.
- I'm not sure he would want to be deluged with mail so, if there is
- enough interest, I could post it.
-
- --
- ===================================================================
- Bob Schreibmaier K2PH | UUCP: att!mtuxo!k2ph or k2ph@mtuxo.att.com
- AT&T Bell Laboratories | ARPA: k2ph%mtuxo@att.arpa
- Middletown, N.J. 07748 | ICBM: 40o21'N, 74o8'W
-
- ------------------------------
-
- Date: Wed, 8 Nov 1989 13:09 EDT
- From: Mark Bramwell 519 661-3714 <watmath!julian!business.uwo.ca!MBramwel@uunet.UU.NET>
- Subject: ftp access for mods database
-
- The mods database is now available through the internet.
-
- IP address: 129.100.22.100 HAMSTER.business.uwo.ca
-
- If you want to post a file, please email it to me.
-
- A separate copy is stored on the IBM 4381 for mail users, therefore
- I need to know if a new file comes in.
-
- Enjoy, let me know if you have any problems.
-
- ------------------------------
-
- Date: 7 Nov 89 13:42:16 GMT
- From: asuvax!anasaz!john@handies.ucar.edu (John Moore)
- Subject: How to use the incoming QSL bureau?
-
- In article <838@soleil.UUCP> gopstein@soleil.UUCP (Rich Gopstein) writes:
- ]
- ]Ok, I admit, I'm one of those people who doesn't have an
- ]envelope at the QSL bureau. How does the bureau work?
- ]I occasionally work DX on the HF bands, and would like to
- ]use incoming and outgoing QSL bureaus. I am an ARRL member,
- ]so that's not an issue.
-
- In fact, why doesn't a knowledgable DX'er post a nice tutorial on
- how to QSL, how to get QSL's from DX, etc. For example, I worked
- MIR last spring. How do I get a QSL? How do I use a bureau. If
- I send a SASE, can I use US stamps, or is there something international
- to put on the return envelope?
-
- I've been a ham 28 years, but have rarely gone after DX, and am
- really baffled. Now that my daughter is interested, I want to know
- what to do.
-
- Thanks in advance.
-
-
- --
- John Moore (NJ7E) mcdphx!anasaz!john asuvax!anasaz!john
- (602) 861-7607 (day or eve) long palladium, short petroleum
- 7525 Clearwater Pkwy, Scottsdale, AZ 85253
- The 2nd amendment is about military weapons, NOT JUST hunting weapons!
-
- ------------------------------
-
- Date: 7 Nov 89 18:13:40 GMT
- From: brutus.cs.uiuc.edu!wuarchive!texbell!texsun!pollux!attctc!mjbtn!root@apple.com (Mark J. Bailey)
- Subject: ICOM IC-740
-
- Hello All,
-
- I recently bought a mint condition Icom IC-740 along with a Ten-Tech 229
- 200w/2kw antenna tuner from a friend. The 740 had the IC-PS740 builtin
- power supply, the IC-EX242 FM option, the IC-EX243 electronic keyer, and
- the FL-52 455kHz CW/RTTY filter installed.
-
- I am interested in trying to locate some of the other options such as the
- FL-44 455 kHz SSB filter, the FL-45 9.0115 mHz CW/RTTY filter, and the
- IC-EX241 marker unit. Also, the manual mentions using a transverter for
- VHF/UHF when the FM unit has been installed. In particular, I would like
- to know what transverter (ICOM #?) could be used with it and if they mean
- theirs or some third party transverter in general, and if it is some third
- party unit, whos would work and where could one be gotten? Of the filters
- mentioned above, I am particularly interested in the FL-44 SSB filter.
-
- Also, the unit has receive only on 17 and 12 meters, but being a micro-
- processor controlled type radio, and that it has specific coverage of those
- bands, I sort of figured that there was probably some sort if transmit
- inhibit diode or something. Can anyone elaborate on this? Has anyone
- succeeded in enabling transmit on these bands?
-
- Any information on anything above would be greatly appreciated. As I
- said the unit is in mint condition and as a new licensee, I am eager to
- gather as much information on it as possible. Any hints and tips from
- other 740 owner would be highly valued too! I noticed that the 740 was
- replaced by the 745 only a year or two after it was introduced (in the
- December 1982 ICOM catalog I think). My guess is that with the new bands,
- and desires for general coverage, and improvements in computer controls
- and memories, the 745 was quickly needed. Does anyone know of any other
- reasons that brought this about?
-
- Please email responses. Thanks in advance!
-
- Mark.
-
- --
- Mark J. Bailey "Ya'll com bak naw, ya hear!"
- USMAIL: 511 Memorial Blvd., Murfreesboro, TN 37129 ___________________________
- VOICE: +1 615 893 0098 | JobSoft
- UUCP: ...!{ames,mit-eddie}!attctc!mjbtn!mjb | Design & Development Co.
- DOMAIN: mjb@mjbtn.MFEE.TN.US CIS: 76314,160 | Murfreesboro, TN USA
-
- ------------------------------
-
- Date: 7 Nov 89 22:39:32 GMT
- From: victim.dec.com!reisert@decwrl.dec.com (Bats aren't bugs!!! 07-Nov-1989 1739)
- Subject: QSLs and SASEs
-
- In article <20598@ut-emx.UUCP>, trey@ut-emx.UUCP (Trey Garlough) writes...
-
- >consider Frank nothing less than discourteous. If you want to "get back
- >at Frank" and his success in contesting because he didn't send you a card,
- >then I suggest that you never call Frank ever again in another contest.
- >Furthermore, I suggest you contact his competitors, giving them a few extra
- >points.
-
- As a member of the YCCC (Yankee Clipper Contest Club), I heartily endorse
- this idea. Work all the W1's and W2's you hear, and leave the W3's behind
- ;-)
-
- jim, AD1C
-
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
-
- "The opinions expressed here in no way represent the views of Digital
- Equipment Corporation."
-
- Jim Reisert Internet: reisert@tallis.enet.dec.com
- Digital Equipment Corp. UUCP: ...decwrl!tallis.enet!reisert
- Littleton, MA 01460
-
- ------------------------------
-
- Date: 7 Nov 89 22:37:38 GMT
- From: victim.dec.com!reisert@decwrl.dec.com (Bats aren't bugs!!!)
- Subject: QSLs and SASEs
-
- In article <20598@ut-emx.UUCP>, you write...
-
- >consider Frank nothing less than discourteous. If you want to "get back
- >at Frank" and his success in contesting because he didn't send you a card,
- >then I suggest that you never call Frank ever again in another contest.
- >Furthermore, I suggest you contact his competitors, giving them a few extra
- >points.
-
- As a member of the YCCC (Yankee Clipper Contest Club), I heartily endorse
- this idea. Work all the W1's and W2's you hear, and leave the W3's behind
- ;-)
-
- jim, AD1C
-
- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
-
- "The opinions expressed here in no way represent the views of Digital
- Equipment Corporation."
-
- Jim Reisert Internet: reisert@tallis.enet.dec.com
- Digital Equipment Corp. UUCP: ...decwrl!tallis.enet!reisert
- Littleton, MA 01460
-
- ------------------------------
-
- Date: 7 Nov 89 17:33:08 GMT
- From: cs.utexas.edu!oakhill!dover!darla!waters@tut.cis.ohio-state.edu (Strawberry Jammer)
- Subject: Tuning dipoles and antennas.
-
- In article <1260002@hpmwtlb.HP.COM> timb@hpmwtd.HP.COM (Tim Bagwell) writes:
- }It is not necessary to have a resonant antenna to efficiently radiate energy.
-
- True
-
- }If an antenna is matched to the source, regardless of how it is matched,
- }all the energy sent down the transmission line is radiated (neglecting,
- }of course, losses in the line , tuner, traps, etc.).
-
- The same is true in an unmatched condition, the only difference is in line
- loss.
-
- }You need to define what you mean by radiation efficiency. The fact is that
- }the radiation pattern will be different for a non-resonant antenna than for
- }a resonant one. But this may be desirable in certain situations.
-
- The normal "model" uses a concept called radiation resistance, that is the
- equivalent "load" presented by the radiated energy. The ratio of radiation
- resistance to other resitsive losses such as the ohmic resistance of the
- antenna and anything else which is electrically coupled to the antenna such
- as the ground determines the efficiency of the antenna. Very few amateur
- installations get over 50% efficiency BTW.
-
- }If your antenna SWR is 2:1, your losing about 10% of the transmitted power back
- }to the transmitter load! This is power that is not radiated anywhere. Contrast
- }this to a non-resonant but matched antenna which will radiate 100% of the
- }transmitted power (again neglecting losses), albeit, into some different
- }pattern. If the antenna length is only slighty off resonance, the pattern
- }will not be affected significantly.
-
- NOT TRUE! SWR losses are dependant on the line loss, they are IN ADDITION to
- the "matched" loss. If the "matched" loss is under 1db (RG213 at <30Mhz for
- example) then 2:1 or 3:1 SWR will add less than 1db additional loss. See the
- ARRL Antenna Book for a very complete treatement of this including charts.
- This becomes significant at VHF/UHF frequencies or when using smaller coax
- such as RG58/59.
-
- If you run high power (say over 100 watts at HF or 25 watts at UHF) then the
- power rating of the cable becomes significant. RG213 is rated at
- approximately 2Kw RF at 30Mhz with 1:1 SWR, with 2:1 SWR the peak voltages
- and currents are twice their 1:1 values so the line can handle only 1Kw RF
- EVEN THOUGH the losses are not increased this much. It is possible to melt
- coax with enough power and it melts at the current nodes, I have seen this
- with 500W into RG58 coax on 2M. The cable actually melted every 38 inches
- (1/2 wavelength)!
-
- }Even if you tune the antenna exactly to resonance, it is unlikely that it will
- }be matched to the transmission line over any practical bandwidth.
-
- An "exact" match is only possible at one EXACT frequency. As much as 1Hz
- deviation will introduce a reactive component, but you won't be able to
- measure it. What is much more useful is the ACCEPTABLE match, normally under
- 2:1 at HF but some Transmitters require under 1.5:1 for full power.
-
- }This again
- }introduces SWR and a reduction in maximum radiated power.
-
- True, but probably not significant. It is quite possible to design antennas
- with ACCEPTABLE matches over each amateur band. A "cage dipole" on 3.5Mhz for
- example imitates a 3ft diameter element and will have less than 2:1 SWR from
- 3.5 to 4 Mhz when properly tuned.
-
- }So I say use a good quality antenna tuner with parallel wire transmission line
- }and don't worry too much about resonating the antenna length.
-
- Workable iff (if and only if) you can use open wire line properly (min 12
- inches from ANY metal the entire length), and want to fiddle with an antenna
- tuner.
-
- Generally bandwidth is not a problem for a dipole build from reasonable size
- wire (no 12 or no 14) except on 80M. There a cage dipole is needed.
-
- Before you start getting too worried about SWR and antenna tuners you need to
- do two things (from the ARRL Antenna Book BTW), (1) ALWAYS measure antenna
- parameters AT THE ANTENNA! and (2) use a noise bridge that tells you reactive
- (L/C) component as well as resictive (R). Trying to do any serious antenna
- tuning with just an SWR bridge is an excersize in futility, you just don't
- have enough information.
-
- THe "in line" SWR meter has really two uses: check to see that nothing has come
- loose and as a quick check of actual line loss. If you check the SWR
- with NOTHING connected at the antenna end (try both open and shorted) then a
- 1:1 match means ALL the power is being lost in the cable - replace the cable!
- I think the ARRL Handbook has a chart relating SWR to actual line loss using
- this method, from memory 3:1 means 1/2 the energy is being lost, and infinite
- SWR means no loss (and of course never happens).
-
- Oh yes DON'T use "RG8" coax unless it is a "name" brand such as Belden, the
- designation is meaningless any more and there is a LOT of "junk coax" out
- there. If you are buying new then by RG213 or similar which IS MIL Spec.
- Try out some of the "cheap" cable with the SWR checking method and you will
- soon see why you need the better stuff.
-
- Especially at HF, "if it conducts it will radiate" the rest is optimization!
-
- Finally - the ARRL Antenna Book is a gold mine of good information, if you
- don't have it then you need it!
-
- *Mike Waters AA4MW/7 waters@dover.sps.mot.com *
- Justice is incidental to law and order.
- -- J. Edgar Hoover
-
- ------------------------------
-
- End of INFO-HAMS Digest V89 Issue #855
- **************************************
-
-