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#1
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I have only used the MFJ 259B. It meets all my needs.
Capabilities as listed in manual: VSWR, coaxloss, capacitance, inductance, impedance [magnitude], return loss, reflection coefficient, distance to fault, resonance mode, percentage of transmitted power, test of stubs, velocity factor, Zo of transmission lines, beverage antennas, adjust tuners, adjust matching networks, test rf transformers, test baluns, test rf chokes. Deacon Dave, W1MCE |
#2
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I only have experience with the MFJ, I have an older 259. Very happy with
it, so much so that at some point I'd like to "upgrade" to the 269. Not sure the 269 is much of an upgrade. I have had two, first one I sent back because the UHF part did not work right. The second was exactly the same. I know of others that had the same problem. The older 259 had problems with the selector switch. The 259B fixed that problem. I like the 259B, works just fine. The Autek is ok, a little harder to use, I think. Needs a new battery every time I go to use it. The switches takes a little getting use to. 73 Al Lowe N0IMW |
#3
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![]() "Arrow146" wrote in message ... Not sure the 269 is much of an upgrade. I have had two, first one I sent back because the UHF part did not work right. The second was exactly the same. I know of others that had the same problem. Bummer. I wanted it to add 440 to my tuning abilities. sigh Well, maybe by the time I can afford one they'll get the bugs worked out. The older 259 had problems with the selector switch. Bingo! I've been having said problems, on some bands I have to hold the switch just right in order to get it to work. Is there a simple fix, other than to send it back to the factory? The 259B fixed that problem. I like the 259B, works just fine. That's good to hear. The Autek is ok, a little harder to use, I think. Needs a new battery every time I go to use it. The switches takes a little getting use to. Not familiar with the Auteks, may have to look at them. 73's de Robert / N4IXT |
#4
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![]() "Tarmo Tammaru" wrote in message ... Jacques, You might want to do what I did, which is to download both the MFJ and Autok instruction manuals. I ended up getting the 269. Compare the specs, but as I recall, the MFJ has a wider impedance range, and if you want to cover VHF, you have to buy two Auteks. I have had no problems with the 269. That includes using it on 432 MHz. There is also a Japanese one, which looks more professional than either of the others, but it only measures up to 300 Ohms. Might be the Kuranishi ? |
#5
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Regarding the sign of reactance.
The MFJ does NOT display the sign. But, I don't find this to be a problem because decreasing reactance with increasing frequency is CAPACITIVE and increasing reactance with increasing frequency is INDUCTIVE. So, a minor variation in frequency tells me the type of reactance. Deacon Dave. |
#6
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![]() The MFJ does NOT display the sign. But, I don't find this to be a problem because decreasing reactance with increasing frequency is CAPACITIVE and increasing reactance with increasing frequency is INDUCTIVE. Hi Dave, The MFJ-259B manual states this is "usually" the case, and that is what I always do. Usually and always are not exactly the same. I do seem to remember this discussed a few years back, and someone provided evidence this was not always the case. They quoted Smith Chart proof. For the life of me I can't find the thread, and haven't had time to play with the chart to confirm. This method always (so it seems) works for me, but there are always exceptions. 73 Gary N4AST |
#7
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Jim, the reactance at the antenna can be any value. The reactance at the
input to the transmission line, with VSWR, can be any OTHER value. The point is ... at the measurement point, where ever that is, at the antenna or at the transmission line, a determination of either Inductive or Capacitive reactance can be measured with the MFJ 259B. Deacon Dave, W1MCE + + + JGBOYLES wrote: SNIP I do seem to remember this discussed a few years back, and someone provided evidence this was not always the case. They quoted Smith Chart proof. SNIP , but there are always exceptions. 73 Gary N4AST |
#8
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The point is ... at the measurement point, where ever that is, at the
antenna or at the transmission line, a determination of either Inductive or Capacitive reactance can be measured with the MFJ 259B. I agree Dave, I just wish I could find that thread, or knew why MFJ said "Usually". 73 Gary N4AST |
#9
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JGBOYLES wrote:
The MFJ does NOT display the sign. But, I don't find this to be a problem because decreasing reactance with increasing frequency is CAPACITIVE and increasing reactance with increasing frequency is INDUCTIVE. Hi Dave, The MFJ-259B manual states this is "usually" the case, and that is what I always do. Usually and always are not exactly the same. I do seem to remember this discussed a few years back, and someone provided evidence this was not always the case. They quoted Smith Chart proof. For the life of me I can't find the thread, and haven't had time to play with the chart to confirm. This method always (so it seems) works for me, but there are always exceptions. For instance, a G5RV's feedpoint reactance is +j160 at 9.17 MHz and +j98 at 9.18 MHz, i.e. decreasing reactance with increasing frequency. As the anti-resonant point is approached, the resistance increases but the reactance decreases with increasing frequency. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#10
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Dear Jacques:
I think that best, portable, self contained analyzer that is presently available is the "CIA-HF" from Tempo. http://www.aea-wireless.com/cia.htm The same company has other (more new) models that might be more suitable for your tasks. I find it is far more easy to measure with the CIA-HF. (I love my old GR bridge, but it is quite a task to use.) 73 Mac N8TT -- J. Mc Laughlin - Michigan USA Hi there, I want to buy an antenna analyser HF and/or VHF. Could be MFJ or Autek. But I don't have experience with theses equipments. Following you what could be the best one ? 73 de ON5MJ - Jacques. |
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