Re: [Elecraft] dB
There you go Jim shooting yourself in the foot straight off by referring your dB to power! > and I increase my transmitter power by 4:1 (6 dB) Of course the two entities voltage and power are mathematically related, but unless you say to what reference you are using, they can be somewhat meaningless. In the 17 years I spent in the Cable TV industry pre the advent of satellite technology, the dB was always related to voltage at 75 ohms and was understood to be so. The only occasion I remember using dB related to power was when using multiple phased antenna arrays to work out the total output as the gain was increased by a ratio of 3dB in power every time the number of separate arrays was doubled. With a sideways shift into telecoms for the last 20+ years I had to start thinking about dB related to power where 4 times gain or loss when related to power is 6dB as you say. The same 4 times gain or loss is 12dB when related to voltage as used in Cable TV. Irrespective of how the measuring systems for the two industries work, they are calibrated in dB relative to the system you are working with and as such are not directly compatible, thus making a reference when referring to dB gain or loss essential. Perhaps a topic to be discussed further off the Elecraft Reflector if needed. Bob, G3VVT ___ 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] K2 Filters
At 09:57 PM 10/13/2004, Joe - aa4nn wrote... >I wish there was a K2 button you could push to see what filter is active. Push AGC and XFIL together. ___ 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] K2 Filters
Joe, push XFIL and AGC at the same time and you'll see what you want to know. 73, Kurt ___ 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] K2 Filters
I wish there was a K2 button you could push to see what filter is active. As it is, any filter button you push advances to the next filter so you are left with the knowledge of the filter you had been using, so you push the button three more times to get back to where you were when you wanted to know where you were in the first place. k2 is a great radio, tho, I love it. 73, Joe, aa4nn ___ 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] One more re:Atomic Clocks
Whatever you'all do, don't buy TWO atomic clocks. Otherwise you'll never know what time it is. I have two MFJ Radio Controlled clocks that after two years have finally synced in with UTC but even now they are two seconds apart. Go figger. You can manually set the Hours on these clocks but not the minutes & seconds. 73, Joe, aa4nn ___ 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] Serial port keying via the K2 (Logger32)
On Wed, 13 Oct 2004 19:24:17 -0400, john wrote: >I wonder if other K2 owners (with the KI02 option of course!) >are using computer keying? If so, did you implement >it using the DTR or PTT method via the serial port, or >via the parallel port? I have been using DTR keying with WriteLog quite successfully. Depending on your antenna system and the power level at which you are operating, it may be necessary to rebuild the serial interface cable using shielded twisted pair cable. It also helps to correct the pin 1 problems at both ends of the serial keying cable by connecting the shield to the DB9 shell, not the so-called "signal ground." The condition under which I had to take these measures are when I use a long wire that puts a lot of RF in my shack and have my K2/100 fired up. (I do this on 160 and 80, and it gets out pretty well). This would probably NOT be an issue with a good resonant antenna 30+ feet from the shack and fed by a reasonably well matched line. Jim Brown K9YC ___ 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] Serial port keying via the K2 (Logger32)
Hi John: During the last couple of Field Days, using the K2/100, we used the N3FJP FD software and successfully used the serial port for excellent keying. There was really no problem doing this - you just have to build a simple interface in the head of the serial plug. There are a few ways to do this as I'm sure you know. I used a two transistor, two resistor interface so as to use the program or a keyer or just fill in with the paddles (and on-board keyer). I'm sure the limitations of port availability will determine many things. For us, we used a USB-serial interface. Others will use the 'printer' port. BTW, the N3FJP software also allows this. 73, Jamie WB4YDL -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of john Sent: Wednesday, October 13, 2004 6:24 PM To: elecraft@mailman.qth.net Subject: [Elecraft] Serial port keying via the K2 (Logger32) I wonder if other K2 owners (with the KI02 option of course!) are using computer keying? If so, did you implement it using the DTR or PTT method via the serial port, or via the parallel port? Are there advantages to one method over another? Thanks! John K5MO ___ 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] Serial port keying via the K2 (Logger32)
I wonder if other K2 owners (with the KI02 option of course!) are using computer keying? If so, did you implement it using the DTR or PTT method via the serial port, or via the parallel port? Are there advantages to one method over another? Thanks! John K5MO --- Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.727 / Virus Database: 482 - Release Date: 7/26/04 ___ 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] One more re:Atomic Clocks
I don't have enough pockets for another device, so I just use the alarm in my Verizon phone. Their CDMA network is synched to GPS, so most of the time the alarm rings within seconds of when it is set to go off. My awakening is usually less precise... N7WY > > From: Daniel Reynolds <[EMAIL PROTECTED]> > Date: 2004/10/13 Wed PM 10:11:56 GMT > To: elecraft@mailman.qth.net > Subject: [Elecraft] One more re:Atomic Clocks > > The newest and smallest Oregon Scientific Atomic Alarm Clock can be had for as > little as $6-7 (www.froogle.com ... search for RM982A - click on Price: Low to > High). This clock has the same features as my little RM103A - except the > 'indiglo' style light - although the small manual page from Oregon > Scientific's > web site suggests that it does have a back-lit display (punch the snooze > button > on top for the light). > > - Daniel / AA0NI > > ___ > 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 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] RS sale items (more)
Michael, N4NMR wrote: "They (RS) had a special sale on the RS version of an Atomic portable alarm clock. Only $20. And it is a nice size for packing or for on the desk. Normally $30, I think. Nice clock with super lighting. Number is 63-964. Only drawback is that you can't set it for UTC." == >From time to time WalMart sells an "atomic" desktop alarm clock made by Oregon Scientific (model RM103A). It can be set to display UTC with no problem and it's ideal for the ham shack I bought one for $11.98. 73, de Earl, K6SE ___ 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] One more re:Atomic Clocks
The newest and smallest Oregon Scientific Atomic Alarm Clock can be had for as little as $6-7 (www.froogle.com ... search for RM982A - click on Price: Low to High). This clock has the same features as my little RM103A - except the 'indiglo' style light - although the small manual page from Oregon Scientific's web site suggests that it does have a back-lit display (punch the snooze button on top for the light). - Daniel / AA0NI ___ 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] RS sale items (more)
I picked up a small bedside LCD atomic alarm clock with Indigo style lighting about 2 years ago at WalMart for about $10-15. It is silver with black and runs off a single AA battery. I am able to adjust it for UTC, but I must readjust it with each time change. I think it was made by Oregon Scientific. Here's one just like it for $17. http://donrowe.com/oregon_scientific/rm103a.html When I figured out the model number, I used google.com and froogled for RM103A. I found this same model for $13. http://www.buyreliant.com/oregon/rm103a.htm The RM103A lets me set it to 24 hour mode. Here's another one I stumbled upon for $8 - although I can't vouch as to whether or not it will allow for UTC time. http://www.softwareandstuff.com/CES10290.html To keep this post On-Topic ... I find that the RM103A clock fits fairly nicely next to my portable digital thermometer, MH2 mike, and Palm-key when I pack my K2 in its aluminum tool case. - Daniel / AA0NI --- Michael Bower N4NMR <[EMAIL PROTECTED]> wrote: > They had a special sale on the RS version of an Atomic portable alarm clock. > Only $20. And it is a nice size for packing or for on the desk. Normally > $30, I think. Nice clock with super lighting. Number is 63-964. > (www.radioshack.com didn't show it as a sale item (still shows $20) but the > sign at the store did). Only drawback is that you can't set it for UTC. > Not a biggy in my mind. ___ 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] RS sale items (more)
Last week I was at my friendly RS getting a new alarm clock. Lost my old one. They had a special sale on the RS version of an Atomic portable alarm clock. Only $20. And it is a nice size for packing or for on the desk. Normally $30, I think. Nice clock with super lighting. Number is 63-964. (www.radioshack.com didn't show it as a sale item (still shows $20) but the sign at the store did). Only drawback is that you can't set it for UTC. Not a biggy in my mind. They also had a special on batteries. Well, the special on batteries is not that super but the batteries come in a nifty case. It is touted as a can holder that says it will hold 4 cans of soda or whatever. But I didn't see it that way. I saw it as a nifty carrier for something like the PAC-12 or MP-1. It is bright red (so it is easy to find) and has a shoulder/carrying strap. Haven't tried it yet but looks like it should work great. Price on the battery pack/cooler says $20 but the sale was for $10. Michael N4NMR ___ 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] dB
On Wed, 13 Oct 2004 07:27:52 EDT, [EMAIL PROTECTED] wrote: >3dB gain reference to what? > >Without a reference decibel values are meaningless. Horse puckey. Without a reference they do not tell you the voltage or power in a circuit, but they can certainly tell you the differences between two voltages or powers, and that can be QUITE meaningful. For example, you are in the UK and I am in Chicago, and I increase my transmitter power by 4:1 (6 dB) and change nothing else. My signal at your location will get 6 dB stronger, independent of the reference used by the voltmeter you choose to measure them, and the signal to noise will also improve by 6 dB, again, independent of that voltmeter's reference. If you must have a reference it is the signal before I increased by power! Once you use the word "gain" you make dB quite meaningful. The most formal definition of gain using dB is for power -- 10 * log (P2/P1), where P2 is the output power and P1 is the input power. But if the impedance is the same for the two powers, the gain in dB is 20 * log (V2/V1). BOTH of these expressions are VERY meaningful, and no reference must be defined! Or, looking at it another way, P1 (or V1) is the reference. Also, many circuits operate as voltage amplifiers, where power is essentially insignificant. Thus it is also entirely correct to speak of the voltage gain in dB, and that is also 20 * log (V2/V1). And, again, no reference level need be defined. Further, if we wanted to MEASURE the gain in dB, we could measure the voltages and do the math, or we could use a voltmeter calibrated to ANY voltage reference for dB, subtract the input voltage in dB from the output voltage in dB, and that would be the gain. Again, the reference is unimportant (so long as we don't change streams in mid- horse). On the other hand, if we want to measure power gain, we would, indeed, need to consider the resistance at both input and output. While the telecom industry was the first to define the Bel and did so in terms of power, virtually all modern instrumentation that gives a readout in dB with respect to any reference is REALLY a voltmeter. That voltmeter may include a load resistor (with a switch to remove it from the circuit), or it may not. Hope this helps. Jim Brown K9YC ___ 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] Curious behaviour of XV50 LEDs
Hi I have completed construction of an XV50, in fact I finished it a while ago, and it all seems ok except for one thing. The Tx power LED display only lights one at a time, even though I have GRPH=BAR and OPT=PERF selected on the K2. It does the same if GRPH=DOT is selected, too. Is this possibly due to an assembly fault? If so I'd be glad of an indication of where to look. I have done very careful inspections of my soldering and can see no dodgy joint that may be the culprit. Is there perhaps one connection that may cause this, or any diagnostic procedure that I can follow to trace the fault? I am using it as the only XV connected to my K2. the K2 software is displayed as '2.01H 1.02', and the XV50 U1 has a label with 1.6e on it. I have K2 #2378 (without the 100W amp etc) with the A to B updates and K160RX, KNB2, KIO2, KDSP2, KSB2 and KAT2 installed. An external meter shows that the power going out to the antenna is what it should be according to the one lit LED. I must have done something silly to get this effect, but I am flummoxed. Has anyone else experienced this phenomenon? I've seen a lot of problems solved on this reflector, and hope that the kind and knowledgeable people out there may be able to help with this one. I normally read any Email -- it's almost only this reflector, in digest form -- once a week on Sunday evening, so please forgive delays in replying to any response to my plea. 73 all Harry Weston M0SOP ___ 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] Mojo!
Woohoo!!! Long Island, NY to Dijon, France...with 3 Watts! I was very excited to work HI with 5 Watts some mos. back, and glad to feel likewise again last night. I didn't think I'd be able to be heard through the other stations calling Paul, F9KP. There's something I feel is worth mentioning. When he came back with a partial call sign followed by a ?, the freq went dead silent and I was allowed to repeat my call a few times completely in the clear...very kewl! I did not use the K1 for this one. Instead, I used it's kissing cousin...a NorCal 40 A. Vy 73 de Bert WA2SI FISTS #9384 QRP ARCI #11782 ___ 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] Re: BL1 Balun
Joe, Todd, Group, It's time for me to get on my soap box again. The BL1 is a great balun, I haven't seen a better one on the market so the answer is not to find a better one, you can't. It should take 100 watts and not overheat, even when running into a SWR of 10:1, provided its load impedance is not too high. What is happening when the balun heats up is that you are did consider the impedance of its place in the feed line, and it is too high for the balun. Actually, the impedance on the open wire feed line varies from near zero to several thousand ohms in the distance of a 1/4 wave on the feed line. For example, take a full wave dipole on 40, 135' long, and feed it with open wire line. The impedance at 1/4 wavelength from the antenna is near zero. Go another 1/4 wavelength along the feed line, and it is several thousand ohms, an impossible situation for any balun. So you need to cut a length off the feed line, in this case on the order of 8', and your impedance will be somewhere in-between. A balun will work there but will not work when the impedance is several thousand ohms. Remember, the impedance of the feed line repeats itself every 180 degrees, or 1/2 wavelength. Just because you are using a 450 ohm line doesn't mean the impedance is 450 ohms, It depends upon the load at the antenna end and its length. 4:1 baluns will work into a SWR of up to 10:1, provided the impedance and voltage is not high. For that matter so will a 1:1 balun. Moving along the feed line changes the voltage and impedance, but does not change the SWR. How do you tell what the losses in a balun are? On the BL1, and other small balun kits, feel the wires after you have been operating a few minutes. If the balun feels hot or even warm to the touch, it is dissipating too much power, and you need to change the position in the feed line where you place it. A good balun will run about 94% efficient into a 7:1 SWR (my measurements) provided the impedance is not too high. Losses of 6% at 100 watts will not melt the balun. At a SWR of 1:1 the losses are half that, so a balun is not lossless, but manageable. How do you cut the feed line? There's a table on page 17 of Practical Wire Antennas, by John D Heys G3BDQ available from the ARRL, that shows lengths of 1/2 the antenna length plus feed line to avoid. My experience is that when you avoid these lengths, you can use a balun. It will amaze you :-) 73, Chas, W1CG At 02:20 PM 10/12/2004, Todd Fonstad wrote: Joe, AA4NN, posted: "With K2/100 100w out after two QSOs on 40m overall about 40 minutes the BL1 balun is quite hot to the touch. This is the first time I have used the BL1 with a CF Zepp. Amazing SWR 1:1 80m-10m, works great. I'm thinking I might need to glue a heat sink on that toroid. Anybody done this or am I too much QRO and heat is normal. hi" I have used the BL-1 at both QRP and 100 watt levels on a couple of ladder-line fed doublets designed for multi-band operation. If you are using the ATU, the 1:1 SWR you are observing is what the K2 is "seeing" courtesy of the tuner. The actual SWR presented to the balun may be very high. The heat you observed from your balun is wasted RF. My BL-1 has quickly heated, then saturated, using 100 watts into both 265' and 176' doublets on 160, 80, and 40 meters. It is fascinating, although dismaying, to see the SWR LEDs on the ATU rise from green (low SWR) to red (high SWR) in a matter of seconds as saturation occurs. I'll continue to use the BL-1 at QRP levels but will "wind my own" more robust balun for QRO operation. 73 Todd N9NE ___ 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 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] Question about K2's T7 windings
3dB gain reference to what? Without a reference decibel values are meaningless. With voltage, 3db gain is a value greater by one half and is only applicable if the impedances remain the same across the item of equipment you are measuring. When referred to power, 3dB gain is greater by x 2 (double). Most of the measurements carried out professionally in telecoms are related to power and do have a specific reference such as dBm (reference to 1mW), etc. which makes life a whole lot easier. Traditionally in the Cable TV industry the decibel is related to the voltage at 75 ohms. Bob, G3VVT ___ 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
