Re: Topband: New MFJ 259C available
As I looked at things over the years, very few people want VNA's that attach to PC's, and that market is covered anyway. I thought a 259 revision wth direct conversion receivers and a wide frequency range, and a calibrate function, and just basically do what the 259B does now, would have been much better. The RigExpert handheld series of complex impedance analyzers pretty much fit that goal. The AA-54 is in the same price class as the MFJ-259B and has +13 dBm output power. It doesn’t have the frequency range of the 259B but it will accurately cover HF through 6m. At roughly 2x the price, the AA-600 gets you a serious 600 MHz handheld analyzer with OSL calibration and PC graphing connectivity. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Thanks, Jim! That's good information, I'll look into it! Thanks! Most of my VNA work in recent years was in the design, tuning and matching of embedded antennas for 900 MHz, 1.4 GHz and 2.5 GHz for electricity, gas and water meters home-area networks and personal security devices. I mostly used a little Smith Chart program called WinSmith 2.0 that was sufficient for my tasks. Those programs you have listed sound interesting, indeed! I'll check 'em out! Many thanks! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Jim Brown Sent: Wednesday, March 05, 2014 12:25 AM To: topband@contesting.com Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:04 PM, Charlie Cunningham wrote: I'd also like to be able to apply VNA measurements to some of my HF antennas and I might be willing to take a laptop out there to do that, but I could also just calibrate out the feedline to move the measurement plane out to the antenna and do the measurments from indoors! Would be nice to have the capability! Charlie, Virtually all of the major vector analyzers can write impedance data files in a standard plain text format (called Touchstone) that can be imported by modeling programs like SimSmith. They also allow you to do TDR of the system, so you can subtract out the feedline. From there you can design matching networks. There's a piece on my website that lists several decent analyzers, then shows you to use SimSmith to do these things. SimSmith is FREE, and runs in Java. Dan, AC6LA, has some wonderful Excel spreadsheets that work with this data. One of them will take open circuit and short circuit sweeps for a piece of transmission line and compute Zo, Vf, and attenuation vs frequency. Most of his spreadsheets are free. Dan also sells a spreadsheet that automates EZNEC and, I think, will do optimization. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
On 3/5/2014 7:15 AM, Paul Christensen wrote: +13 dBm may be more than adequate depending on that unit's (AA-54) selectivity. I would like to see it's real world performance in the presence of a strong AMBC field. Paul, There is a VNWA users Yahoo group, which is called VNWA. :) Yahoo groups are easy to join. You could ask about AMBC issues there, and there's a good chance that someone in your area owns one and might bring it to your QTH for a test. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Hi Paul, Where is a selectivity spec or a description?? 73 Tom - Original Message - From: Paul Christensen w...@arrl.net To: topband topband@contesting.com Sent: Wednesday, March 05, 2014 10:15 AM Subject: Re: Topband: New MFJ 259C available +13 dBm is nothing. That is only 20 milliwatts or 1 volt across 50 ohms if that is at 50 ohms. +13 dBm may be more than adequate depending on that unit's (AA-54) selectivity. I would like to see it's real world performance in the presence of a strong AMBC field. For the CIA/VNA class of analyzers with their high selectivity, that power level is definitely more than sufficient. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3705/7155 - Release Date: 03/05/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Hello, In my qth you need at least 30 dBm (1 Watt) for reliable measurements with a broadband detector. The 160m antenna picks up such an amount of signals that with less power you do not get correct results. I allways use a selective methode with bridge, receiver and signal source. Kees, PE5T -- From: Tom W8JI w...@w8ji.com Sent: Wednesday, March 05, 2014 7:08 PM To: Paul Christensen w...@arrl.net; topband topband@contesting.com Subject: Re: Topband: New MFJ 259C available Hi Paul, Where is a selectivity spec or a description?? 73 Tom - Original Message - From: Paul Christensen w...@arrl.net To: topband topband@contesting.com Sent: Wednesday, March 05, 2014 10:15 AM Subject: Re: Topband: New MFJ 259C available +13 dBm is nothing. That is only 20 milliwatts or 1 volt across 50 ohms if that is at 50 ohms. +13 dBm may be more than adequate depending on that unit's (AA-54) selectivity. I would like to see it's real world performance in the presence of a strong AMBC field. For the CIA/VNA class of analyzers with their high selectivity, that power level is definitely more than sufficient. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3705/7155 - Release Date: 03/05/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Where is a selectivity spec or a description?? 73 Tom Tom, Apart from the N2PK analyzer, I don't know any published selectivity spec. The detector minimum res. bandwidth of the N2PK unit is 7 Hz and produces +4dBm into 50 ohms. FWIW, RigExpert put together a comparison of analyzers based on measurement topology. For sure, it's a biased piece -- especially when the MFJ product is discussed. So, keep that in mind. http://www.rigexpert.com/index?s=articlesf=aas The plot below shows how well the N2PK analyzer can selectivly ignore a large multi-volt base voltage from three nearby AMBC stations located 2 miles to the south. Two of the AM stations are Non-D in the daytime. One is 15KW, the other is 5KW. Note that the T is resonated to 1420 kHz, right where the stations transmit (look for 1320, 1460, and 1530 kHz). The attached plot shows total RF immunity on the X trace. On the R trace, small blips do show - each representing the local AMBC stations. However, even these can be easily ime-averaged away in the software. http://72.52.250.47/images/N4NN.jpg Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
(look for 1320, 1460, and 1530 kHz). ... and looks like a couple other locals at 1010 and 1060. 73, ... Joe, W4TV On 3/5/2014 2:03 PM, Paul Christensen wrote: Where is a selectivity spec or a description?? 73 Tom Tom, Apart from the N2PK analyzer, I don't know any published selectivity spec. The detector minimum res. bandwidth of the N2PK unit is 7 Hz and produces +4dBm into 50 ohms. FWIW, RigExpert put together a comparison of analyzers based on measurement topology. For sure, it's a biased piece -- especially when the MFJ product is discussed. So, keep that in mind. http://www.rigexpert.com/index?s=articlesf=aas The plot below shows how well the N2PK analyzer can selectivly ignore a large multi-volt base voltage from three nearby AMBC stations located 2 miles to the south. Two of the AM stations are Non-D in the daytime. One is 15KW, the other is 5KW. Note that the T is resonated to 1420 kHz, right where the stations transmit (look for 1320, 1460, and 1530 kHz). The attached plot shows total RF immunity on the X trace. On the R trace, small blips do show - each representing the local AMBC stations. However, even these can be easily ime-averaged away in the software. http://72.52.250.47/images/N4NN.jpg Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
The AIM4170 family is not included in this review? Gregg W6IZT -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Joe Subich, W4TV Sent: Wednesday, March 05, 2014 2:33 PM To: topband@contesting.com Subject: Re: Topband: New MFJ 259C available (look for 1320, 1460, and 1530 kHz). ... and looks like a couple other locals at 1010 and 1060. 73, ... Joe, W4TV On 3/5/2014 2:03 PM, Paul Christensen wrote: Where is a selectivity spec or a description?? 73 Tom Tom, Apart from the N2PK analyzer, I don't know any published selectivity spec. The detector minimum res. bandwidth of the N2PK unit is 7 Hz and produces +4dBm into 50 ohms. FWIW, RigExpert put together a comparison of analyzers based on measurement topology. For sure, it's a biased piece -- especially when the MFJ product is discussed. So, keep that in mind. http://www.rigexpert.com/index?s=articlesf=aas The plot below shows how well the N2PK analyzer can selectivly ignore a large multi-volt base voltage from three nearby AMBC stations located 2 miles to the south. Two of the AM stations are Non-D in the daytime. One is 15KW, the other is 5KW. Note that the T is resonated to 1420 kHz, right where the stations transmit (look for 1320, 1460, and 1530 kHz). The attached plot shows total RF immunity on the X trace. On the R trace, small blips do show - each representing the local AMBC stations. However, even these can be easily ime-averaged away in the software. http://72.52.250.47/images/N4NN.jpg Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
My bad, I see it now. -Original Message- From: Gregg W6IZT [mailto:gregg.w6i...@gmail.com] Sent: Wednesday, March 05, 2014 2:43 PM To: 'topband@contesting.com' Subject: RE: Topband: New MFJ 259C available The AIM4170 family is not included in this review? Gregg W6IZT -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Joe Subich, W4TV Sent: Wednesday, March 05, 2014 2:33 PM To: topband@contesting.com Subject: Re: Topband: New MFJ 259C available (look for 1320, 1460, and 1530 kHz). ... and looks like a couple other locals at 1010 and 1060. 73, ... Joe, W4TV On 3/5/2014 2:03 PM, Paul Christensen wrote: Where is a selectivity spec or a description?? 73 Tom Tom, Apart from the N2PK analyzer, I don't know any published selectivity spec. The detector minimum res. bandwidth of the N2PK unit is 7 Hz and produces +4dBm into 50 ohms. FWIW, RigExpert put together a comparison of analyzers based on measurement topology. For sure, it's a biased piece -- especially when the MFJ product is discussed. So, keep that in mind. http://www.rigexpert.com/index?s=articlesf=aas The plot below shows how well the N2PK analyzer can selectivly ignore a large multi-volt base voltage from three nearby AMBC stations located 2 miles to the south. Two of the AM stations are Non-D in the daytime. One is 15KW, the other is 5KW. Note that the T is resonated to 1420 kHz, right where the stations transmit (look for 1320, 1460, and 1530 kHz). The attached plot shows total RF immunity on the X trace. On the R trace, small blips do show - each representing the local AMBC stations. However, even these can be easily ime-averaged away in the software. http://72.52.250.47/images/N4NN.jpg Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Hi Paul, Reading the link, it looks like there are very few analyzers that use receivers, either superheterodyne or direct conversion. The AA-54 is in the class of broadband detectors, which are all sensitive to external RF. http://www.rigexpert.com/index?s=articlesf=aas Scrolling down the page to near the bottom, we find the superheterodyne or direct conversion frequency selective types. This is the mistake I think MFJ made, not doing a selective detector. The single overwhelming problem is external voltage. 73 Tom . - Original Message - From: Paul Christensen w...@arrl.net To: topband topband@contesting.com Sent: Wednesday, March 05, 2014 2:03 PM Subject: Re: Topband: New MFJ 259C available Where is a selectivity spec or a description?? 73 Tom Tom, Apart from the N2PK analyzer, I don't know any published selectivity spec. The detector minimum res. bandwidth of the N2PK unit is 7 Hz and produces +4dBm into 50 ohms. FWIW, RigExpert put together a comparison of analyzers based on measurement topology. For sure, it's a biased piece -- especially when the MFJ product is discussed. So, keep that in mind. http://www.rigexpert.com/index?s=articlesf=aas The plot below shows how well the N2PK analyzer can selectivly ignore a large multi-volt base voltage from three nearby AMBC stations located 2 miles to the south. Two of the AM stations are Non-D in the daytime. One is 15KW, the other is 5KW. Note that the T is resonated to 1420 kHz, right where the stations transmit (look for 1320, 1460, and 1530 kHz). The attached plot shows total RF immunity on the X trace. On the R trace, small blips do show - each representing the local AMBC stations. However, even these can be easily ime-averaged away in the software. http://72.52.250.47/images/N4NN.jpg Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3705/7155 - Release Date: 03/05/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
I also recommend the VNWA. It is a true network analyzer. The MFJ is basically a SWR meters and does not accurately display Impedance. Mike N2MS - Original Message - From: Grant Saviers gran...@pacbell.net To: Carl k...@jeremy.mv.com, topband@contesting.com Sent: Tue, 04 Mar 2014 02:23:04 - (UTC) Subject: Re: Topband: New MFJ 259C available My VNWA V2.6 factory assembled Vector Network Analyzer, designed by DG8SAQ is available for $400 incl shipping, USA only, as I upgraded to the newer version V3. 1KHz to 1300MHz, 2 port, USB powered, no cables or standards included. see www.sdr-kits.net for full specs Radcom review at http://sdr-kits.net/VNWA/RadCom_VNWA_Review.pdf Grant KZ1W _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
I had a look at the matching Rosenberger calibration standards and for the money, the kit is a bargain. At first, I was disappointed to see what amounts to only 1% resistive load accuracy. The displayed image on the website shows a calibration standard that reads about 49.5 ohms. But, the software automatically compensates for the disparity. It's possible to use a DMM with 4-wire resistance capabilities to measure the exact DC resistance then enter the value in a table to get excellent operating accuracy, certainly better than 0.1%. Depending on the accuracy needed, the VNWA software allows for several other important compensating factors. http://www.hamcom.dk/VNWA/Rosenberger%20Cal%20standards_rev2.pdf My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm still looking for input from anyone who has made such measurements. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Im waiting for N6LF to add that to his review results. http://www.antennasbyn6lf.com/files/vna_comparisons.pdf Carl KM1H - Original Message - From: Paul Christensen w...@arrl.net To: topband@contesting.com Sent: Tuesday, March 04, 2014 10:25 AM Subject: Re: Topband: New MFJ 259C available I had a look at the matching Rosenberger calibration standards and for the money, the kit is a bargain. At first, I was disappointed to see what amounts to only 1% resistive load accuracy. The displayed image on the website shows a calibration standard that reads about 49.5 ohms. But, the software automatically compensates for the disparity. It's possible to use a DMM with 4-wire resistance capabilities to measure the exact DC resistance then enter the value in a table to get excellent operating accuracy, certainly better than 0.1%. Depending on the accuracy needed, the VNWA software allows for several other important compensating factors. http://www.hamcom.dk/VNWA/Rosenberger%20Cal%20standards_rev2.pdf My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm still looking for input from anyone who has made such measurements. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
True!! Check out the prices of the Cal kits for the Agilent VNAs! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Jim Brown Sent: Tuesday, March 04, 2014 1:36 PM To: topband@contesting.com Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
I have made sweeps of my 160m T on many occasions as I tuned it, added elevated radials, and then installed a remote series capacitor switch to tune the entire band per a W8JI suggestion. There was no interference from AMBC, I'd be glad to forward the sweeps. My current QTH does not have a nearby BC transmitter however. At my former QTH in San Jose, CA I had elevated clear line of sight to a 50kw BC 1Mhz at 3 miles. The MFJ269 was useless (sold) and my AIM4170 (pre VNWA, still use it now and then) worked but showed obvious glitches in the sweeps of both 40m and 80m elevated verticals on metal roofs. I had 1v of the BC signal on my power lines. I haven't needed RF measurement of resistance better than 1% in any antenna, choke, or filter testing. There is also a 3rd party VI test kit (and support in the software) for the VNWA that enables more accurate testing of very low and high Z, as the VNWA 50 ohm internal bridge is good for about a 20:1 ratio or so. I have a 6.5 digit 4 lead DMM but never thought I needed to measure a standard that accurately. The yahoo VNWA group gets into very detailed and esoteric (to me) discussions of the psec and fF issues in standards, cables, and connectors for GHz work. There is a raft of good info from basic tutorials to esoterica linked from the posts. Also, HP/Agilent have a large number of excellent VNA technical reports/tutorials also available on the web. Tom's (DG8SAQ) manual is comprehensive, he is continuously adding software enhancements, and is responsive to posts. I've tuned/measured several 5B4AGN filter kits and other off the shelf single band units, some of them went back for re-tuning as they were out of spec. Measuring ferrite chokes is easy. I've probably tuned/checked a dozen different antennas. If you calibrate at the far end of the feedline, then the measurement is accurate at the antenna at its input terminals - cool and no climbing. I'm still a bit of a novice, am learning at lot and working up to retuning a 70cm multicavity filter as I have not yet used the time domain filter tuning technique. Overall, the VNWA is my most frequently used test equipment, a VNA is the RF engineers VOM. Grant KZ1W On 3/4/2014 7:25 AM, Paul Christensen wrote: I had a look at the matching Rosenberger calibration standards and for the money, the kit is a bargain. At first, I was disappointed to see what amounts to only 1% resistive load accuracy. The displayed image on the website shows a calibration standard that reads about 49.5 ohms. But, the software automatically compensates for the disparity. It's possible to use a DMM with 4-wire resistance capabilities to measure the exact DC resistance then enter the value in a table to get excellent operating accuracy, certainly better than 0.1%. Depending on the accuracy needed, the VNWA software allows for several other important compensating factors. http://www.hamcom.dk/VNWA/Rosenberger%20Cal%20standards_rev2.pdf My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm still looking for input from anyone who has made such measurements. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
SMA for the 24GHz, open, thru and short. I also have high end adaptors to N, APC, etc. There may even be an old type N cal kit from back in the eighties Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: 'Carl' k...@jeremy.mv.com; j...@audiosystemsgroup.com; topband@contesting.com Sent: Tuesday, March 04, 2014 2:53 PM Subject: RE: Topband: New MFJ 259C available Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Well, SMA is probably the most generally useful. With the adaptors in place, we just have to make sure that we include the adaptors in our calibrations. When it gets to be really witchy is when we need to calibrate a miniature coax or semi-rigid line to solder into a PC board to measure at the input of an IC, or balun, or printed antenna etc. Then we have to trim the line very carefully and tack tiny surface mount 50 ohm and 0-ohm resistors across the line to calibrate - each step being done under a microscope! Tedious - but it can be done! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 3:01 PM To: Charlie Cunningham; j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available SMA for the 24GHz, open, thru and short. I also have high end adaptors to N, APC, etc. There may even be an old type N cal kit from back in the eighties Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: 'Carl' k...@jeremy.mv.com; j...@audiosystemsgroup.com; topband@contesting.com Sent: Tuesday, March 04, 2014 2:53 PM Subject: RE: Topband: New MFJ 259C available Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
I have the BH microscope, stand, light, table, etc as well as a hot plate and access to a bonder when needed. Plus various knives, blades, scalpels, gold plated needle point iron, etc for fine tuning (-; I still do a bit of prototyping for former employers and stuff for myself to 24 GHz. Its down at HF I need to improve some of the test equipment. Carl KM1H Sent: Tuesday, March 04, 2014 3:19 PM Subject: RE: Topband: New MFJ 259C available Well, SMA is probably the most generally useful. With the adaptors in place, we just have to make sure that we include the adaptors in our calibrations. When it gets to be really witchy is when we need to calibrate a miniature coax or semi-rigid line to solder into a PC board to measure at the input of an IC, or balun, or printed antenna etc. Then we have to trim the line very carefully and tack tiny surface mount 50 ohm and 0-ohm resistors across the line to calibrate - each step being done under a microscope! Tedious - but it can be done! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 3:01 PM To: Charlie Cunningham; j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available SMA for the 24GHz, open, thru and short. I also have high end adaptors to N, APC, etc. There may even be an old type N cal kit from back in the eighties Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: 'Carl' k...@jeremy.mv.com; j...@audiosystemsgroup.com; topband@contesting.com Sent: Tuesday, March 04, 2014 2:53 PM Subject: RE: Topband: New MFJ 259C available Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
This sure doesn't sound like topband to me ! Price W0RI Well, SMA is probably the most generally useful. With the adaptors in place, we just have to make sure that we include the adaptors in our calibrations. When it gets to be really witchy is when we need to calibrate a miniature coax or semi-rigid line to solder into a PC board to measure at the input of an IC, or balun, or printed antenna etc. Then we have to trim the line very carefully and tack tiny surface mount 50 ohm and 0-ohm resistors across the line to calibrate - each step being done under a microscope! Tedious - but it can be done! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 3:01 PM To: Charlie Cunningham; j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available SMA for the 24GHz, open, thru and short. I also have high end adaptors to N, APC, etc. There may even be an old type N cal kit from back in the eighties Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: 'Carl' k...@jeremy.mv.com; j...@audiosystemsgroup.com; topband@contesting.com Sent: Tuesday, March 04, 2014 2:53 PM Subject: RE: Topband: New MFJ 259C available Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
No, Price! Way above Topband in frequency, but the principles of Vector Network Analysis and calibrating out the cables to move the measurement plane to the end of the cable are the same at 1.8 MHz as they are at 2.5 GHz. And the Smith Chart applies at all frequencies from near DC to daylight! J 73, Charlie, K4OTV From: HAROLD SMITH JR [mailto:w0ri...@sbcglobal.net] Sent: Tuesday, March 04, 2014 6:32 PM To: Charlie Cunningham; 'Carl'; j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available This sure doesn't sound like topband to me ! Price W0RI Well, SMA is probably the most generally useful. With the adaptors in place, we just have to make sure that we include the adaptors in our calibrations. When it gets to be really witchy is when we need to calibrate a miniature coax or semi-rigid line to solder into a PC board to measure at the input of an IC, or balun, or printed antenna etc. Then we have to trim the line very carefully and tack tiny surface mount 50 ohm and 0-ohm resistors across the line to calibrate - each step being done under a microscope! Tedious - but it can be done! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 3:01 PM To: Charlie Cunningham; j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available SMA for the 24GHz, open, thru and short. I also have high end adaptors to N, APC, etc. There may even be an old type N cal kit from back in the eighties Carl KM1H - Original Message - From: Charlie Cunningham charlie-cunning...@nc.rr.com To: 'Carl' k...@jeremy.mv.com; j...@audiosystemsgroup.com; topband@contesting.com Sent: Tuesday, March 04, 2014 2:53 PM Subject: RE: Topband: New MFJ 259C available Those should surely be accurate enough, but what kind of connectors? Charlie, K4OT V -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Carl Sent: Tuesday, March 04, 2014 2:41 PM To: j...@audiosystemsgroup.com; topband@contesting.com Subject: Re: Topband: New MFJ 259C available Can HP microwave loads be used? I have a set good to 24 GHz and another to 50 GHz. Carl KM1H - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Tuesday, March 04, 2014 1:35 PM Subject: Re: Topband: New MFJ 259C available On 3/4/2014 7:25 AM, Paul Christensen wrote: My only concern with the VNWA is in its ability to measure Topband antenna systems where sweeps are required into the AMBC band. I'm a VERY happy owner of the 3E model VNWA. I've made measurements on my 160M antennas with no difficulty, but I'm out in the boonies, not close enough to strong BC signals to have seen any issues. As to precision of calibration loads -- after I got the VNWA, I did a search looking for calibration loads, and quickly learned that if you want better than 1% precision, it's easy to spend as much for the load as for the VNWA itself! 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com http://www.avg.com/ Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7150 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
This sure doesn't sound like topband to me ! That's what I was thinking. I don't understand why we have to use microscopes and scalpels for 1.8 MHz. 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
On 3/4/2014 4:10 PM, Mike Waters wrote: That's what I was thinking. I don't understand why we have to use microscopes and scalpels for 1.8 MHz. It all depends on the degree of precision that you need for whatever project you happen to be working on. I work all bands between 1.8 MHz and 900 MHz, and I occasionally need test equipment for all of them. Also, errors can add with either a positive or negative sign, as a phase angle. Impedance measurements with a vector analyzer are done with a mathematical equation that can be the difference of numbers that are nearly equal, so a small error in the raw data can cause a greater error in the measured Z. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
So you can see better to stuff more wire in a binocular core. But I agree with Charlie that the principles are the same and it often may be easier to test an idea about a 160M antenna at say 10 or 6M where a 1/2 wave is only 9' for the latter. OTOH the discussion was also about cal kits and precision loads for the German VNA and some of us with microwave experience were just comparing things. If I intend to buy a portable VNA it certainly wont be for single band use either. Carl KM1H - Original Message - From: Mike Waters mikew...@gmail.com To: topband topband@contesting.com Sent: Tuesday, March 04, 2014 7:10 PM Subject: Re: Topband: New MFJ 259C available This sure doesn't sound like topband to me ! That's what I was thinking. I don't understand why we have to use microscopes and scalpels for 1.8 MHz. 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7153 - Release Date: 03/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
I thought a much more useful item would have been a 259 revision that was totally immune to RFI, and still did about the same stuff over a wider frequency range. As I looked at things over the years, very few people want VNA's that attach to PC's, and that market is covered anyway. I thought a 259 revision wth direct conversion receivers and a wide frequency range, and a calibrate function, and just basically do what the 259B does now, would have been much better. That would have solved all the major issues, and not cost a fortune or required a computer. My 259B does 99% of what I need, but would be a whole lot better with a cal correction (open, short, load), sweep, wide range, and receivers with a phase detector instead of a diode bridge. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Well, I might be willing to use a VNA that attaches to a computer in my Lab, if I could get away with much lower cost than one of the Agilent or Rhode and Schwarz VNAs. I'd like to have the capability to cover the 2.5 GHz band and go considerably higher so I could look at harmonic filters for 2.5GHz. I'd also like to be able to apply VNA measurements to some of my HF antennas and I might be willing to take a laptop out there to do that, but I could also just calibrate out the feedline to move the measurement plane out to the antenna and do the measurments from indoors! Would be nice to have the capability! I have seen a commercial VNA with a lot of capability that attaches to a Computer for considerably less than a good Agilent VNA! I'm thinking about it when some of my invoices get paid! 73, Charlie, K4OTV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Tom W8JI Sent: Tuesday, March 04, 2014 9:48 PM To: topband Subject: Re: Topband: New MFJ 259C available I thought a much more useful item would have been a 259 revision that was totally immune to RFI, and still did about the same stuff over a wider frequency range. As I looked at things over the years, very few people want VNA's that attach to PC's, and that market is covered anyway. I thought a 259 revision wth direct conversion receivers and a wide frequency range, and a calibrate function, and just basically do what the 259B does now, would have been much better. That would have solved all the major issues, and not cost a fortune or required a computer. My 259B does 99% of what I need, but would be a whole lot better with a cal correction (open, short, load), sweep, wide range, and receivers with a phase detector instead of a diode bridge. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: New MFJ 259C available
Another entry into the analyzer battle, the C model covers 530KHz to 230 MHz. http://www.mfjenterprises.com/MFJ-259C_Flyer.php I wonder why it didnt go down to 470 KHz which would include the coming 600M bandthe new Topband. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
There is a lot of CW and digital activity on 474.2 (USB). (Load wsjtx on your computer and see.) MFJ missed the boat. On Mon, Mar 3, 2014 at 7:57 PM, Carl k...@jeremy.mv.com wrote: I wonder why it didnt go down to 470 KHz which would include the coming 600M bandthe new Topband. _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
Nah, it will have to go to at least 136 KHz; the future Topband. Carl KM1H - Original Message - From: James Rodenkirch To: Carl ; Top Band Contesting Sent: Monday, March 03, 2014 9:04 PM Subject: RE: Topband: New MFJ 259C available They'll be offering a 250 kHz to 500 kHZ version later, Carl, to sell ya! From: k...@jeremy.mv.com To: topband@contesting.com Date: Mon, 3 Mar 2014 20:57:22 -0500 Subject: Topband: New MFJ 259C available Another entry into the analyzer battle, the C model covers 530KHz to 230 MHz. http://www.mfjenterprises.com/MFJ-259C_Flyer.php I wonder why it didnt go down to 470 KHz which would include the coming 600M bandthe new Topband. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4335 / Virus Database: 3705/7148 - Release Date: 03/03/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New MFJ 259C available
My VNWA V2.6 factory assembled Vector Network Analyzer, designed by DG8SAQ is available for $400 incl shipping, USA only, as I upgraded to the newer version V3. 1KHz to 1300MHz, 2 port, USB powered, no cables or standards included. see www.sdr-kits.net for full specs Radcom review at http://sdr-kits.net/VNWA/RadCom_VNWA_Review.pdf Grant KZ1W On 3/3/2014 5:57 PM, Carl wrote: Another entry into the analyzer battle, the C model covers 530KHz to 230 MHz. http://www.mfjenterprises.com/MFJ-259C_Flyer.php I wonder why it didnt go down to 470 KHz which would include the coming 600M bandthe new Topband. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
