[Elecraft] USB Support - K3, K2?
John, I think that is a very small fee per device or may be per some sort of assignment ID codes to be kept unique. Primarily the USB standards cater to the mass production market. Most of the options for a design expect thousands of units to be produced in a production run. The USB interface is a nasty little complicated thing and requires a large investment in study time to get familar with it. Also, there's no telling for just how long a time it will remain valid. It is a product of the modern PC age. The serial interface is slow and cumbersome and lacks many standards which tend to constrain things rather than help sometimes. It predates personal computers and to some extent, predates computers, going back to the days of the teletype. While not offering high speed and not being suitable for transferring large amounts of information quickly, it can be superior to the USB in some ways - specifically - wired interfaces for distances longer than 10 or 20 feet. For some 'secondary' hardware standards like RS485 instead of RS232, it can provide interfaces in excess of 1000 feet. Although USB style to RS232 interface devices may eventually become specialty products not found at the local computer store due to a lack of need from most users, they should remain around as specialty items. If RS232 is suitable for the job, then it might even be a safer bet than USB to use for a product that should be expected to be around for a decade or more rather than the typical life expectancy of 10 weeks for the usual computer junk. Most of my USB/serial ports were from the office supply place and labeled as USB interfaces for PDAs. I'm sure there are better suited ones for RF environments and probably cheaper ones too. But as long as USB survives, they should provide me with the ability to connect to real devices I need, such as radios, telescopes, TNCs, and gizmos that I can build and program PCs to operate without having to read several hundred pages of barf just to do something simple - like a dual azimuth antenna rotator controller. Such a homebrew project is impractical with USB, if not virtually impossible, with most options having development kits that would cost more than buying a commerical rotator in the first place. As for USB, it's the best thing that's happened to RS232 serial ports since willard gates succeeded in getting the native ones banned because now there's no seriously low limit as to how many you can stick on your PC and they are the size of a pigtail cable with a long connector housing on the end. What's more, they are finally well supported as serial port devices by the OS. best regards, Charles wb5izd Date: Tue, 07 Aug 2007 13:23:26 -0400 From: John Huggins [EMAIL PROTECTED] Subject: Re: [Elecraft] USB Support - K3, K2? To: Richard Kent [EMAIL PROTECTED] Cc: Elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=ISO-8859-1; format=flowed I am not sure, but can point to one example that does include a USB chip in its design that takes care of the conversion from USB to serial. It is the WinKeyUSB interface from K1EL. It is quite possible the purchase of the chip might pay such fees indirectly. If it does the fees must be low as the cost of the kit is under $50. Richard Kent wrote: I thought I heard or read that including an USB controller into a piece of equipment requires one to pay a licensing fee to the organization that maintains the USB definition. If this is true that could be why many devices do not include USB compatibility. The cost may be too much for the number of devices to be sold. Anyone know for sure?? Rick Kent WD8AJG ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] vibroplex bug
- Original Message - From: Charles Allison To: elecraft@mailman.qth.net Sent: Friday, July 27, 2007 8:20 AM Subject: RE: [Elecraft] vibroplex bug Chris, My wife got the bug bug, the straight key bug, the iambic key bug... fairly recently too. She is a dedicated but fairly slow cw operator as well and keeps a 1960 vintage vibroplex, a blackwidow iambic and a modern russian knockoff of the world war II Junkers german key all tied to her K2 at the same time. She's also got 3 or 4 more bugs, mostly Vibroplex. One can buy weights for the Vibroplex to slow it down and I think she's got 2 weights on her regular key. One of the keys had a 4-40 screw hole tapped in the side of the weight. It was explained that this used to be done by some operators that installed a copper tube, squashed and drilled, to provide an extra weight as a lever that could be used to immediately change speeds by pushing the top outward or inward - without having to loosen the weight screw, position the weight and then tightening the weight screw down again. best regards, Charles wb5izd Message: 1 Date: Thu, 26 Jul 2007 18:08:38 -0700 (PDT) From: Chris Kantarjiev [EMAIL PROTECTED] Subject: RE: [Elecraft] vibroplex bug To: elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] I got the bug bug about a year ago, and found a 1923 Vibroplex in decent shape. Yeah, the dot rate is way too fast to learn with. After exploring many options for slowing it, I went to a local hobby shop and got a bit of brass tubing that has an ID that is a slip fit over the rod. About 6 did it for me - slows the dots right down and still allows me to do some adjusting. 73 de chris K6DBG ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: Detecting the LO [was: plexiglass] (Vic K2VCO) clarification
Hi, I remember reading about the Brits searching for spies who were tuned to certain frequencies that transmitted coded information to the agents who might not have even had transmitters. A quick clarification. The IF stage is 455kc and the LO is an HF oscillator that is offset from the tuned frequency by 455kc so that the difference is fed into the IF stage for amplification. (I decided to use Kc rather than khz as wwii predates the change in terms lol). By searching for the actual LO frequency - the Brits counterintellegence people could identify which radios were listening to the enemy's coded messages and avoid wasting time on those listening to Churchill's speeches. best regards, Charles wb5izd ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: Solar Panels (Douglas Todd)
Hi Doug, My wife has a 50 Watt solar panel she uses for emergency power. They are definitely not the transportable or affordable kind - unless you find one taken out of commercial service and then they tend to be cheaper than buying new small ones. She is a net control station and a local ARES member and we are 30 miles off the water on the lower TX coast. The panel is used to charge a 12V deep discharge marine battery - approximately 100 AmpHr. The panel provides up to about 5 amps. Even that scarcely provides enough power for net control activities 2 to 4 hours per day using the full 100 Watts. One must scale the system to the radio and to use. Obviously, you wouldn't want this setup for a kx1 backpacking system. The most common batteries are called sealed lead acid and provide decent power for size and weight. A 4 AH or 7AH battery is not too unreasonable for man portable usage and can generally power a few watts for a reasonable length of time. In general, one sees the C/10 term for what the battery is rated at. A 7AH battery doesn't mean 7 amps for one hour but rather 7/10 amp per hour for 10 hours and .350 Amps should last for a good 20 hours. Also, charging rates tend to be about this rate also, C/10 although full charge will probably not be reached in just 10 hours at that rate. Once the battery is selected for your requirement, then you need to select a solar panel that can deliver the charging rates needed to charge the battery, typically in aaround 10 hrs. Buying new solar panels is not for most people. Anything affordable is usually too small for any use other than to float charge (keeps a battery from discharging). The surplus stores offer a significant discount on new pricing for larger panels. Once the panel is obtained - one needs a switching regulator for solar panels of that size. Some hams offer them and potted commercial ones are also available for not too much cost as well. These are needed because the open circuit voltage could be 20 VDC for a 12.6 volt panel without the regulator. If you're in ARES RACES emcomm arena, it might be possible to find even the larger panels from your local gov. that has replaced them on those solar powered school crossing lights. best regards, Charles Allison wb5izd (husband of k2/100 and kx1 owner) - Original Message - From: [EMAIL PROTECTED] To: elecraft@mailman.qth.net Sent: Tuesday, July 04, 2006 3:02 AM Subject: Elecraft Digest, Vol 27, Issue 4 Send Elecraft mailing list submissions to elecraft@mailman.qth.net To subscribe or unsubscribe via the World Wide Web, visit http://mailman.qth.net/mailman/listinfo/elecraft or, via email, send a message with subject or body 'help' to [EMAIL PROTECTED] You can reach the person managing the list at [EMAIL PROTECTED] When replying, please edit your Subject line so it is more specific than Re: Contents of Elecraft digest... Message: 8 Date: Mon, 3 Jul 2006 10:56:08 -0700 From: Douglas Todd [EMAIL PROTECTED] Subject: [Elecraft] Solar Panels To: elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=iso-8859-1 I'm interested in using solar panels to power the K2 for emergency/field day operations and am wondering what sort of experience others have had. The panels seem expensive: about $100 for a 5 watt panel but with battery and a low power draw of the K2, they look like they can sustain operations for extended periods of time. How does this work in practice ? Is there enough 'juice' delivered to keep a station operational ? How about portability ? Thanks to everyone in advance for your responses. Douglas Todd (KE7GYQ) -- ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: Elecraft Horizontal Loop Antenna (Kevin Shaw)
Kevin, I've built 2 low loop antennas that are currently in operation. My wife uses one for 80 and 40m regional communications, essentially the whole state of texas plus surrounding states. It is composed of insulated wire with a current balun fed by rg58 and is up about 15 feet and is diamond shape. She uses a K2 /100 with kat100. In general on those bands, it can function nvis mode and provide up to 2 s-units of improvement over my gap challenger vertical on both transmit and receive. This prompted my other creation for a friend that had just moved into a restricted neighborhood near houston. We created a loop using aluminum electric fence wire and insulators mounted under the eaves of his house, about 8 ft. above the ground. The reason for this was not so much cost but because there are evidently some sort of proximity alarm sensors that use similar materials. Also, even though the wire stretches across the brick facade in front where there are not soffits, it is not visible from the 20 feet away. The wire is fed with several feet of 450 ladder line and a homemade 4/1 balun, The ladderline was cut so as to be run almost to the entrance on the house but not so as to lay on the ground. Tuning is done with an mfj manual tuner and works with a 100 watt ricebox rig. Operation of this antenna is not nearly as good as my wife's but our friends signal rivals that of an attic mounted trap dipole antenna located about 30 miles from there which is owned by a mutual friend. Regional communications on these antennas is exercised every weekday morning at 6am on 80 meters with a group of friends and conditions have ranged from good to unbelievably horrible over the last few weeks. For regional comm. on 80 and 40 I heartily reccomend the loop low down, but 12-18 ft seems to be best. I think it best that the loop be put around the back yard rather than around the house but it's hard to guess what you might get away with if anyone can see it. For dx, there's no beating a vertical in this case, maybe disguised as a flagpole. best regards, Charles wb5izd 21. Horizontal Loop Antenna (Kevin Shaw) Message: 21 Date: Wed, 21 Dec 2005 14:58:05 -0500 From: Kevin Shaw [EMAIL PROTECTED] Subject: [Elecraft] Horizontal Loop Antenna To: Elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=us-ascii I've been thinking about what kind of antenna to put up. With my height and deed restrictions, I'm quite limited. I've thought about putting up a horizontal loop antenna. Basically I was planning to run some enameled magnet wire around the perimeter of the roof (I have no plans on running more than 10 watts). The wire would lay under the shingles so it can't be seen. The antenna will be 1 WL long on 80 meters. I'll run coax down to the K2 + ATU. This is similar to The Loop Skywire described in the November 1985 issue of QST. Anyone have experience (or see a problem) with this antenna? Thanks, Kevin N8IQ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: Algorithm for Tuner (Don)
Date: Fri, 16 Sep 2005 08:51:33 -0700 From: Don [EMAIL PROTECTED] Subject: Re: [Elecraft] Algorithm for Tuner To: Bill Coleman [EMAIL PROTECTED] Cc: elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=response Bill, It's worse than that. Even with my reed relays (very fast compared to conventional relays) I have to allow 10 mS for them to settle and the A/D requires a millisecond or so to read the forward and reflected power. Don, Why not take an approach normal to the manual tuner. That is capacitance to mid scale and adjust L to best. Then adjust C up or down from midscale for min. ? Doing this with a possible repeat for missing the L value by +/- 1 has always yielded me good fast manual results on my old mfj tuners and doesn't require a tremendous number of iterations or complex programming. best regards, Charles wb5izd A reiterative multilevel slope-sensing algorithm using decreasing granularity* is the answer. I have been slowely creeping up on a satisfactory solution and, depending on distractions, hope to have a fairly fast autotuner in a week or so. Suggestions from the list have been very helpful. * my term ... don't try to look it up! ;) Don K7FJ On Sep 15, 2005, at 11:22 AM, Craig Rairdin wrote: In this particular case, if you were to iterate over all possible combinations of L and C it's only necessary to store the best result so far and compare the current result to the best result. If the current result is better, it becomes the new best. Now you have no sorting at all and your time is order N instead of order N^2. The problem with the exhaustive search is there are 2^17 = 131,072 combinations to try. (256 cap and inductor values, plus reversing the whole L network) It takes a few ms for each relay to physically switch. If you can try 100 combinations a second (10 ms), that's still about 20 minutes to try them all. Even with 1 ms switching time, you're still looking at 2 minutes to find a match. A tough problem. Bill Coleman, AA4LR, PP-ASELMail: [EMAIL PROTECTED] Quote: Not within a thousand years will man ever fly! -- Wilbur Wright, 1901 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Fw: [Elecraft] Re: CW in Emergencies
I guess Eric didn't get this message sent directly to him the first time with specifics examples concerning CW during Katrina that we are aware of here. best regards, Charles Allison wb5izd - Original Message - From: charles allison [EMAIL PROTECTED] To: EricJ [EMAIL PROTECTED] Sent: Wednesday, September 07, 2005 8:25 AM Subject: Re: [Elecraft] Re: CW in Emergencies? (WAS: Dropping the Code Test) ka5klu sent 10 to 20 hw msgs per night into MS starting monday night Don, ac5xk, did some msgs on monday night via cw also. These are the only ones I know of because my wife is involved in the hw networks and these are the only ones she was interfacing with that were doing cw into the area - at least that she told me about. As for cnn, are you sure they were really there? The media has been known to fake things in the past as well as regularly distorting what they report. In any case, I've never seen a media team doing emergency or hw traffic message handling, except as an occaisional diversion for the tv camera to record. As for bpl, it's an abuse of existing technology that provides inferior results compared to alternatives and causes harmful interference to a lot more than just amateur radio. Just wait til it comes out that it's possible to decode the data going through remotely and that some geek is selling decoding systems on the gray market so that crooks as well as the fbi can monitor what people are doing on it. note that such things have been done by intellegence services all the way back to monitoring emitted noise from the old telex machines. - Original Message - From: EricJ [EMAIL PROTECTED] To: 'charles allison' [EMAIL PROTECTED]; elecraft@mailman.qth.net Sent: Tuesday, September 06, 2005 2:55 PM Subject: RE: [Elecraft] Re: CW in Emergencies? (WAS: Dropping the Code Test) WHOA! Back up the bus, there, Charles. I'd like a citation for that one! I have been searching google (a major investor in BPL) diligently and have not seen a single reference to CW in this disaster. Not one. Actually, Craig fingered the reality. The FIRST communications out of the affected area were via CNN and the major networks who had pre-staged cameras and crews in the area. We're living a myth. All of us. Hams, ham clubs, the ARRL. We're going to get blind-sided. That quote in the WSJ from a BPL rep saying amateurs were nothing, is a WARNING. With all the billions of dollars behind BPL, and hams defending their existence with fairy tales, we are ripe for an attack from powerful, moneyed interests and they will eat our lunch. Eric KE6US www.ke6us.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of charles allison Sent: Tuesday, September 06, 2005 9:17 AM To: elecraft@mailman.qth.net Subject: [Elecraft] Re: CW in Emergencies? (WAS: Dropping the Code Test) The first communications with the affected area from the outside were HF CW. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: An Opportunity for CW Ops K2 use in emergencies
Johnny, My wife's rig is a k2/100 with most or all internal accessories and kat100. She has been quite active in health and welfare traffic handling for Katrina and has been involved on a regular basis with traffic nets since shortly after upgrading to general class. She is just starting to learn CW traffic handling now but is already quite proficient at ssb traffic handling and net control functions. Her K2 has worked admirably for her use on a daily basis for this. It is an excellent rig and is nice, small and powerful. She has it mounted in a portable wood box along with a power supply and a 2m rig. On her desk, she keeps 2 12V 7.5 AH lead acid batteries on a trickle charger and can switch to backup power with a single switch on the front panel of the box. The wood box has antenna cables, ground strap, a battery cable plug (anderson connectors like the k2/100 upgrade), and the power supply ac plug coming out of the back. it takes only a minute or two to disconnect and carry to the car. Additionally, she has a 50 watt solar panel and deep discharge marine battery (about 100 Ah ??) available for long term use without commercial power. This system appears to be able to keep the battery charged on sunny days even with rather heavy use. While she has a small portable vertical 40-10 screwdriver, we tend to prefer setting up either a loop or dipole at 15 ft or below for portable use. These are 80-10 meter antennas that run NVIS on 80 and 40m capable of blanketing the state of TX and beyond with usable signals during just about anything but the poorest of conditions. So in a nutshell. The k2 is capable of being one of the best sort of emergency radios possible for HF. I don't think it is used substantially only because I believe that there are relatively few K2s out there compared to a multitude of other brands and radios from current and previous eras. Also, being a kit or built by an individual, tends to be a disadvantage when considered for purchase by an entity associated with emergency operations. best regards, Charles wb5izd -- Message: 26 Date: Tue, 13 Sep 2005 10:10:59 +0800 From: Johnny [EMAIL PROTECTED] Subject: Re: [Elecraft] An Opportunity for CW Ops To: Ron D'Eau Claire [EMAIL PROTECTED], elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; format=flowed; charset=iso-8859-1; reply-type=original Hi Group, I have read so many message about emergency net in US. I am interested in knowing whether K2 has been greatly used in emergency communication. Can I have your advice? 73 Johnny Siu VR2XMC builder of s/n 1146, 4225, 4165 ... ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: CW in Emergencies? (WAS: Dropping the Code Test)
Hi, One thing that most miss in this debate, especially on the gov. is the realization that communications is a skill that is every bit as important as the technical knowledge required to turn a piece of wire into a working antenna. It seems on the gov. side that communications skills means the glib ability to push BS on a receptive audience and not convey information in an efficient manner. Pushing license renewals, birthday greetings and the like on a regular basis by whatever net means, cw, phone, gives one a great advantage over those who don't While the disadvantage of CW is both speed and accuracy among those of us with little skill, it's advantage is massive. It offers maximum range for minimum power and equipment, conditions that prevail in most bad disasters. While using a computer digital mode can even increase this range / power - it requires a power hog of a computer. Sure vhf is the preferred short range method, maybe 40 - 50 miles max with a good repeater and with a network of repeaters, there's no limit. Guess what happens when there is no repeater and the most you can get is about 15 ft off the ground with a makeshift antenna. You can forget regional communications unless you have a series of stations to relay. The benefit of amateur radio emcomm is that it can function in devastated areas without the necessity of a communications infrastructure. It can function with minimal equipment and there are many skilled communicators who can improvise, unlike button pushing dispatchers. The emcomm classes teach that there are preferred means for various types of messages for desired security, accuracy and speed. They also explain the nature of the situation and how and why the standard infrastructure communications of the gov. fail. Amateur radio emcomm is not obsolete nor is it a simple rudimentary system of obsolete technology. It covers the full range of technology from CW to HF radio links straight into the computer packet radio and even the internet email network via Winlink. It is comprised of vhf and hf, portable, mobile and fixed stations both within and outside the affected area. VHF and HF comm, digital, CW and voice radio comm are merely tools to be selected for use in the particular situation. This disaster, Katrina, and the NOLA levee break the next day - which is its own disaster, a massive localized catastrophe that was precipitated by Katrina but actually happened after the storm went through, is a good example of what is described in those ARRL emcomm courses. Things were made worse by the fact that many hams living there evacuated and were not allowed back in to many areas, some legitimately like NOLA were very dangerous due to two legged predators while other areas were merely storm damaged. The absence of amateur communications during the predictable communications infrastructure failure made things worse, perhaps in NOLA, far worse. The first communications with the affected area from the outside were HF CW. It provides the most bang for the complexity and battery backup power makes for simple but low power operation. Also, the sunspot cycle is near minimum and HF comm has been rather poor for weeks with various propagation problems. The next mode to come up was voice, ssb which works while the generators are running and is down when the ops have to scramble for more gasoline. It took about 3 days for the digital modes to be restored or setup, the direct Winlink internet modes and packet modes. VHF may work ideally inside the affected areas for short ranges but with massively tall antennas and/or repeaters, the coverage of a handitalky is more in city blocks than in miles. Tall antennas and working repeaters in an emergencies are not only rare occurances, they are a scarce resource when things really get going at the local level. In our area, which is flat as a pancake, vhf comm can get us to the nearest city and some of the surrounding counties, comfortably with repeaters, possible without. There are prepositioned VHF/UHF/HF stations at the weather service, emergency op center, some hospitals, and other places. Our regional communications is HF which has greater than the repeater system down here. Amateur radio and amateur volunteers form an essential core of volunteers for the emergency management professionals and are offered formal training for both natural and manmade disasters along with the professional first responders - however that is intended to enhance our abilities at communicating in disasters rather than to put us in the teletubby suits and scba to mop up some toxic spill. A demonstration of communications difficulities was done as a part of a level I or II hazmat class to emphasize the virtual impossibility of detailed communications between responders over the radio. It involved describing how to construct a lego block vehicle out of the blocks in order to match a built one in another room by communicating over vhf handitalki.
[Elecraft] Re: K2/100 Portable Battery Pak Question (Gottlieb, Jonathan)
My wife, kd5txd has a k2/100 with a small battery pack backup system at her desk. It is homemade with 2x, 12v, 7.2AH, lead acid batteries in parallel with a 1-2A trickle charger. She normally runs about 90 watts output power on the k2 and has used this power set up as net control for as long as about an hour, doing ubstantial SSB transmitting. Lead acid batteries are rated at 7.2 AH assuming either 10hr or 20hr discharge. Discharging at a faster rate will degrade the AH rating to some extent so that a 7.2AH battery rated for discharging 0.72 A over 10 hours will not deliver 7.2 Amps for the a whole hour or 3.6 Amps for a full 2 hours. Note that 90 Watts SSB is much lower average power than 90 watts of rtty or cw where it is transmitting full power and drawing full current. Since we already have two battery systems, the small 14.4AH unit mentioned above and a 100AH deep discharge battery with 50Watt solar panel, we are not likely to get another system soon. If we were, I'd be inclined to get the larger quickstart unit from WalMart or something similar. That unit offers a 19AH battery along with light, battery booster cables and I believe two 12v accessory plugs. best regards, Charles wb5izd 17. K2/100 Portable Battery Pak Question (Gottlieb, Jonathan) Message: 17 Date: Tue, 2 Aug 2005 13:28:32 -0400 From: Gottlieb, Jonathan [EMAIL PROTECTED] Subject: [Elecraft] K2/100 Portable Battery Pak Question To: elecraft@mailman.qth.net Message-ID: [EMAIL PROTECTED] Content-Type: text/plain; charset=iso-8859-1 Does anybody have any experience using the HFProjects Power-Pak with a K2/100? It is a nice 12v 7ah gel cell with built in trickle charger (www.hfprojects.com). I wouldn't expect it to power the K2/100 at full 100 Watts, but I'm thinking it would be a good way to have a nice power supply for camping or traveling and run the k2/100 at 35-50 watts. Please let me know if anybody has used this successfully. Jonathan Gottlieb WA3WDK k2/100 #4856 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
[Elecraft] Re: stranger than real life
Hi, There's an interesting book called The Measure of All Things which covers the quest for determining the length of the meter for the purpose of creating the ultimate scientifically based system of measurements called the metric system. The author also presents, intentionally or otherwise, additional themes in the book about the migration from what he refers to as savants into what we now call scientists and about some of the pitfalls of bureaucracies and government back 'science'. It's a book that is interesting to read and quite insightful, bordering on being as interesting as the book Longitude which I consider should be a must read for anyone interested in science and technology, especially as a career. One of the observations made in the book was that there are several criteria for a system of measurements. These include practical values for common use and ease of use for the end user and ease of calibration or determination of the validity of the measurement tools. Beyond that, it really doesn't matter. Some things are more convenient to do metric, some are not. Fortunately, only a subset of the original metric system was implemented. We don't have 10 hour days and ten day weeks or 400 degrees in a circle. I'm not sure many could tolerate only 7 more days until the weekend. While there is the claim that the metric system is based upon things physical rather than something arbitrary, like the length of some dead king's foot, this claim is somewhat exagerated. What matters is the ease of reproducing the standard. The meter itself was an attempt to be defined as a particular fraction of the distance from pole to equator at the longitude of Paris, the assumption at the time was that the earth was a perfect sphere which it wasn't. Also, the ultimate accuracy of the measurement was off by several thousands of an inch. The claim of absolute reference to natural phenomenon become questionable when one asks why that fraction and why the meridian through Paris, accuracy aside. It's nice to use meters for wavelength because for us in the states,it's really more abstract than feet and inches and depending on the speed of propagation in the wire/coax, this distance in terms of wavelength can change significantly. As for adapting the metric system, I may use watts and occaisonally meters and grams when appropriate but I have no interest in changing it all for no real benefit. best regards, Charles ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
