--------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4D00010 Date: 04/09/97 From: ROY WITT Time: 07:20am \/To: JEFF EDMONSON (Read 5 times) Subj: SWRs & more power DEBATE Hello Jeff. 08 Apr 97 17:45, Jeff Edmonson wrote to Roy Witt: JE> RW>> I build VHF/UHF yagi's for a commercial customer. RW>> Fortunatly, I can tune them while on or 1/2 wave above the RW>> ground. If I tune an antenna with the swr bridge at the RW>> antenna and then place the swr bridge at the other end of the RW>> coax, there's a difference. 1.2:1 at the antenna, 1.9:1 at RW>> the tx. No amplifier, No antenna tuner, no etc.. Now what do RW>> I tune to get 1.5:1 or less at the tx? JE> JE> tune the coax. With what? A pitch pipe or tuning fork... ... Parking is such street sorrow. * Origin: KB6PI's Antenna Farm * San Diego, CA (1:202/909.10) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00000 Date: 04/09/97 From: RICHARD PLASENCIA Time: 12:04pm \/To: STUART LINFOOT (Read 5 times) Subj: Antennas SL>Howdy All - SL> I just got in to ham and am now full of questions. SL> I want to install a radio and antenna in my car but not shure what way SL>to go. SL> I was told to use a maxrad antenna and find a radio that woulden't SL>have a lot of intermod problems. You would also be surprised with more serious problems than intermod. I had a GM compact (leased). One day out of boredom I thought I'd use my hand held 2 meter rig while driving. Imagine my surprise going down the highway at 60 MPH and all of a sudden as I keyed the hand held the engine stopped dead. Sure enough, every time the hand held was keyed the engine died. So much for modern electronic engine controls/ignition. Bah humbug! 73, Dick, W0RPV * SLMR 2.1a * Dyslexia can warn without striking! --- Maximus/2 2.01wb * Origin: Aardvark's Aquarium -- We all live in one fishbowl. (1:283/121) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00001 Date: 04/08/97 From: WAYNE SAROSI Time: 08:36pm \/To: ALL (Read 5 times) Subj: Field day-5 Field day antennas and kits : part 5 Rotor use on field day: Somehow, rotors have been deemed off-limits in some unsaid word by amateurs during field day operations. This is nothing more than pure BS. If you have a beam antenna then get that rotor under the beam and use it, especially if you are running 'A' for field day. If you believe an amp or two draw on a generator for 30 secs is going to ruin your power source, well ... what can I say. Even in an emergency condition, it is not necessary to run a wire antenna and have a car battery as a source of power every time. But that may be all you have. Rotors work and they work well. Pre-preps include quick disconnects on control cables, lubrication of the bearings, U-bolt de-corrosion and lubrication, pre-testing as a MUST before using a rotor on field day or in emergency use. Rotors can be stored in storage boxes made of wood or old luggage. SOME NOTES: o Do not over rate your rotor. - Light duty means light duty. Don't stack a 10m and 20m beam on a rotor built for a TV antenna. o Do tin the wires before attaching them to rotor and/or controller. - Frayed wires are shorts waiting to happen. o Do not attach the control wires with the control box powered. o Do disconnect via the QD connector when lightning storms are in the area. (MOLEX) - Power down the rotor and use the QD. It's the one item we seem to forget in a lightning storm. -WS --- XRS! 4.50+ * Origin: KB4YLY, Moderator (1:374/73.2) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00002 Date: 04/08/97 From: WAYNE SAROSI Time: 08:37pm \/To: ALL (Read 5 times) Subj: Field day-6 Subject: Field day Antennas and Kits - part 6 Kits: (Weather boxes for rigs) Keeping in mind the kit boxes of a previous posting, a box can be made to house your rig, P/S, tuner, and speaker. For example, an old machinary crate box can be used for this purpose. The box should be about 2' X 1.5' ant the top and at least 1.5' deep with a lid. The box can be cleaned out, sanded, and stained or for that rustic look, Placing handles on the sides makes for an easy lift. The lid can be hinged and a clasp placed on the front for locking. Feed through RF connectors can be installed on the back side for antenna attachment. A fan or pair of fans on eith side can be added for cooling. External power connectors round off the field day / emergency kit. The radio kit could look something like this: _________________________________________________________ | | | | | SPEAKER PAIR VHF rig | | | | | | |<--Fan | | Flow | MIC HOLDER | | | | HF Rig | | | | FAN SWITCH | |_______________________________________________________| leg leg Screw on legs can be added to the box if a table is not available. Also the lid can be removed and legs attached for a seat. -WS --- XRS! 4.50+ * Origin: KB4YLY, Moderator (1:374/73.2) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00003 Date: 04/09/97 From: WAYNE SAROSI Time: 07:56pm \/To: HARVEY HARBICHT (Read 5 times) Subj: Field Day -3a In a message to Wayne Sarosi <06 Apr 97 21:12> Harvey Harbicht wrote: >>Field Day Antennas & Kits - part 3 HH> Parts 1 and 2 never showed up here. Did you send them into the Echo? HH> FB on your posts! HH> KG9EV Yep, but I can repost them. -WS --- XRS! 4.50+ * Origin: KB4YLY, Moderator (1:374/73.2) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00004 Date: 04/09/97 From: WAYNE SAROSI Time: 09:23pm \/To: STUART LINFOOT (Read 5 times) Subj: Antennas In a message to All <08 Apr 97 9:18> Stuart Linfoot wrote: SL> My problem is this: is a Maxrad 2 meter antenna a good way to go on a SL> mobile instulation and what whould be a good radio to use for 2 meters? SL> While keeping the price realitively inexpensive. Welcome to Ham radio. Not familar with the Maxrod antenna. I like the Larsen Antennas. Radios? All the popular brands are very good. I have a ten year old Alinco 24T and no intermod. It's a dual bander. Bought it new. 25w out and works great. I have a Larsen Dual band mag mount. Goes 50 miles here in FL. -WS --- XRS! 4.50+ * Origin: KB4YLY, Moderator (1:374/73.2) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4E00005 Date: 04/09/97 From: MATT SMITH Time: 07:01pm \/To: WAYNE SAROSI (Read 5 times) Subj: Re: STATS at my BBS WS> Just to let you all know : HAM_TECH BEAT HAM FOR THE FIRST TIME WS> IN HAM_TECH ECHO HISTORY on The Bear's Cave BBS 374/73 in weekly WS> stats, 1.3% to 1.0% I'm happy! :-) Is echomail dead? It sure has dropped way off on most all echoes since AOL went unlimited rates. --- Simplex BBS (v1.07.00Beta [DOS]) * Origin: The Spirit of '76 (1:3644/8) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4F00000 Date: 04/10/97 From: JEFF EDMONSON Time: 06:58am \/To: RICHARD PLASENCIA (Read 5 times) Subj: Kw-1 RP> JE>Just where DOES one find a 40 to 50 Hy choke, at half an amp RP> these days? RP> Don't need one that big. Say 5 Henries will do the job and any RP> more are excess. You will need the 0.5 A though. 5 Henries wont do the job. According to the calculations I erformed when I had the 810's in there, a choke of around 90Hys was needed to pass audio down to as low as 100 cycles. I decided that it wasn't *that* important to get *that* kinda quality audio, so opted to go with 40Hy. Will get the rest later tonight, in the mail editor. 73 = Best Regards, -Jeff KA5THB --- FMail 1.02 * Origin: Electronic Avenue * San Antonio, TX * 210-333-0060 (1:387/510) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4F00001 Date: 04/10/97 From: WAYNE SAROSI Time: 08:03pm \/To: MATT SMITH (Read 5 times) Subj: STATS at my BBS In a message to Wayne Sarosi <09 Apr 97 19:01> Matt Smith wrote: >WS> Just to let you all know : HAM_TECH BEAT HAM FOR THE FIRST TIME >WS> IN HAM_TECH ECHO HISTORY on The Bear's Cave BBS 374/73 in weekly >WS> stats, 1.3% to 1.0% I'm happy! :-) MS> Is echomail dead? It sure has dropped way off on most all MS> echoes since AOL went unlimited rates. Who knows really. HAM_TECH has been gaining people while the rest of the echos are losing. At least what I can see here. I used to get 2-5 per day. Now it's 8-15 per day. I call that an increase. We have already discussed the internet drain on FIDO but Ham-Tech seems to be a place where people can still talk without the crap on the internet. It's civil. Small but civil. -WS --- XRS! 4.50+ * Origin: KB4YLY, Moderator (1:374/73.2) --------------- FIDO MESSAGE AREA==> TOPIC: 188 HAM TECH Ref: E4F00002 Date: 04/01/97 From: RALPH MOWERY Time: 07:49am \/To: CHARLES MOODY (Read 5 times) Subj: SWRs & more power DEBATE CM>RW>I have a Bird, with a variety of elements. Even *it* is affected by a CM>RW>near RF field. I repeat. SWR has nothing to do with *power level*. CM>........................................................................... . CM>I don't know, but so far I have consulted several other hams who have been CM>around a very long time and Ohms law can not be argued. In each case each CM>of my friends have informed me, and demonstrated that more power is more CM>resistance which is more SWR. Our debate is a good one, but when I see it CM>on a scope, and see it one an analyzer, and then on some very nice tuners, CM>and SWRs meters, it has been proven to me in a manner I can accept. While you can see it on the swr meters, the power level has nothing to do with the real swr. What you are seeing is the short commings of the meters. Most of them use some diodes and they are not linear. At low levels of voltage (power on the line) they will act more like square law detectors instead of linear detectors. As the voltage is increaced, they become more linear. That is why you seem to have a higher swr with more power. While most swr meters are not that accurate, most will do a very good job of letting you adjust the antenna system for the lowest swr. This is a case of not how accurate the meter is but one where you get a relative indication. If you really want to blow their mind, get about 100 feet of some coax like rg 58 (the small lossey kind) and leave one end open and check the swr at 2 meters and then again around 440 mhz. Then check the swr at 28 mhz. The swr stays the same ( it has to as there is no load so to speek of and it should be off scale on the high side). The swr meter will not indicate this, but varing ammounts of swr. That just goes to show you that you can not always believe what you see. --- WILDMAIL!/WC v4.12 * Origin: Borderline! BBS Fido_Net Concord,N.C. (1:379/37.0)