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I own the FA-VA5 from 4 years, this is my review and description: https://www.pianetaradio.it/blog/antenna-analyzer-fa-va5/

Hi, I have a FA-VA5 but don't know how to use it for TDR. I am not an EE and just plodding along with half a brain and a lot of Trial and Error. Can someone cook Book a 1,2,3,4,etc list of things to do to measure TDR on my Coaxes? I do not know what S21, S11, IZI, etc mean and do not know how to convert the program from meters to feet... So I would need a basic and simple proceedure to do the above. I have trial and errored all the settings to get to a point where i have something like a TDR graph(I think) but do not know how to place Feet on the screen of VNWA. It just measures Time...which I have to correlate to distance. I do not know how to input or output Memories, etc...if that is necessary. Can I plug in a coax and USB, Calibrate VNWA and get a TDR? HOW? Can Meters be converted to Feet? Where? I have looked far an dwide on the Internet but can't seem to find anything that will help em insert the right parameters and select the proper items to get TDR. Help!!! I am assuming this FA-VA5 can do TDR. I've seen somewhere that it can. Thanks for any help. I need a Walk Through. Val N4RJ I appreciate any feedback

A new chat has been created: Hi Michael My e-mail to your t-online address bounces back. Tried a few times. Please advise. thanks Dieter, VK3FFB By: Dieter VK3FFB (group owner) <dpelz@...> View/Join This Chat Do not reply to this message to post to the chat. You can participate in chats only through the group's website.

Dear FA-VA5 users, We may not be the most active group, but we meet the purpose of this group. Questions coming in from time to time are answered and discussed promptly. It is now my pleasure to inform you that we are soon reaching a member count of 200 (196 now). This will be a great milestone for the FA-VA5 user group. Thanks to all members who posted questions in the past. Any unexplained observations with the FA-VA5 are worth a post. There are no dumb questions :) I'd like to thank all members who responded to posted questions in the past and I encourage you to do so in the future. I also want to ask members to consider becoming a group editor. Just send me a message if you feel inclined to being a group editor. Please feel free to post suggestions for the improvement of the group service. thanks Dieter, VK3FFB Group Owner

Dieter VK3FFB (group owner) <dpelz@...> added the album FA-VA5 BNC connector soldering ( /g/fa-va5-users/album?id=281762 ) : This image was sent by Jan (SDR-KITS) to illustrate the required soldering of a critical BNC grounding pin. "I have seen this issue at least two or three times when FA-VA% Customers complained about poor quality measurements or VA5 locking up. The problem was found by me after a customer return of a faulty FA-VA5. This joint needs to be soldered from the top component side and needs a lot of heat, at least 60W iron with 3mm or 4mm wide solder bit. A badly soldered joint can play up after time because of strain on the BNC connector after regular use. Although the BNC connector may still show connected to GND via the backplane, measurement accuracy may suffer if the BNC ground terminal is not making good contact with the top copper." click on "Photos" left to see the image.

Hi! I have an FA-VA5 since a few years back and would now recalibrate it, but I can't find "Cal/Port Model Master data", is there an opportunity to access them or are they exclusive to every FA-VA5? Regard Roger 73 de SM0LTV

Is there a source or sources for the FA-VA5 in Canada? If not, where would be supplier and a website with information to order for shipping to Canada? VE1VQ/VA6NS

Hi Frank, I own a FA-VA5 and I am more than satisfied with its performance. It is very accurate when carefully calibrated. Admittdedly, the 3-button user interface was slightly frustrating when I started to use it but I quickly learned to live with it. It is not a real problem. However, a rotary knob (encoder) and a button or two would have been better in my opinion. Anyway, don't let this stop you from buying it. FA-VA5 is a very good and solid instrument with impressive performance/price ratio. I don't know about the warranty, ask your dealer. 73 Johan SM6LKM Frank wrote:

This is my first post. I am Old. Licensed for 65 years so my "New Skill" learnin' ain't what it used to be. I have a FA-VA5. I want to use it to do TDR. I need a 1,2,3,4 Cookbook to set it up if that is possible. Can someone help me with this. I have VNWA and can put the FA-VA5 on USB, calibrate it and get the screen readout going but that is about all I have accomplished. I have produced what I "Believe" to be a TDR of my K9AY receive antenna feedline coax. I do not see a linear measurement at the base of the screen like other programs I have see show, it is in nanoseconds which can be transformed to Length. My Length conversions on the hlittle carat markers are in Meters....can I change to Feet? I probably went about the wrong way to setup this reading on the chart/scree, can someone please give me a simple Cookbook tutorial and walk me through the setup to get the TDR screen on and accurrate? I don't even know what S21, S11, Memories, and the like mean in setup S1.p etc....IZI included. but I am trying......But I have somehow maneuvered to a screen in VNWA that shows what I believe to be a TDR but unsure of settings/ohms/meters vs time/feet, etc... HELP!!! Val N4RJ (Old and obviously not prepared to use this nice device properly)

Hi and thanks for including me in the group. I recently bought a FA-VA5 analyser 99% built with the standard 100Mhz calibration plugs and all went well in the assembly phase. However, when I came to calibrate the analyser I couldn't find all the settings for the SOL Master calibration ( there are the open and short settings in the manual but not the load figure.) So, I entered the Open and Short settings in both Master and Actual settings and did the master calibration procedure. This took about half an hour as per the manual. However, when testing the analyser against my MetroVNA I find the measurements totally wrong , even to the extent of a 1.13 :1 SWR on the MetroVNA showing as over 700 :1 with Z of 6500 and no J shown. So back i wnet and removed the Open and Short settings and did the master calibration again - same result. I now wonder what it is I've done or not done and am prepared to be admonished from those who know more about Vector Network analysers than I do. All help gratefully received. Thanks and regards Lawrence G4GZG

Best wishes for 2022 to all group members. I am pleased to announce that we now have 166 group members. While the group activity remains relatively low, all question from FA-VA5 users are answered promptly. I would like to encourage everyone to place new messages on - interesting FA-VA5 applications - interesting measurement observations - "unexplained phenomena" Occasionally, we still get critique related to the FA-VA5 manual. One way to things improve here could be a few condensed pages on certain critical aspects of FA-VA5 usage. For this we could start a document on Google Docs with access for multiple authors and reviewers. Any feedback on this proposal is most welcome. 73 Dieter, VK3FFB

Under SWR Single sweep, based on this practically useless manual, how do you tell which side is plus (+) and which is minus (-)??? Thanks.....Ken

Dear FA-VA5 users, For those of you who may not be so familiar with antenna impedance measurements, here are some points to consider: If a reasonably well-matched antenna is measured via a long feeding coax cable, things are pretty straight forward. You connect the coax cable to the FA-VA5 via suitable adapters and measure in the format of choice. You should see a low VSWR at the antenna's frequency(ies) of operation and when changing the FA-VA5 frequency progressively in suitably small steps you should see a departure from the good VSWR in both directions of frequency change. Measuring the two frequencies where VSWR = 2.0 (outer VSWR band edges) is good practice and noting them down for future reference is even better. Measurements at the feedpoint of the antenna, say the center of a halfwave wire dipole, require a bit more attention. If no balun is available, you can still do meaningful measurements if you connect the FA-VA5 via suitable adapters or a coax socket connected to the dipole wires. In this case it is necessary to not touch the FA-VA5 while you are reading the measured results. The reason is that the FA-VA5 housing carries an RF potential and therefore your hands may load and detune the antenna and thereby falsify the measurement. Using a known good 1:1 balun symmetry transformer is best practice and the "hand problem" should not exist or be negligibly small. A good test of measurement accuracy is simply by "hand-on - hand-off". You might argue that the direct measurement without balun can't be right because the antenna is symmetrical (2 wires) whereas the FA-VA5 is unsymmetrical (BNC socket). That is true in principle but because the FA-VA5 is "electrically small" - at least at HF frequencies - the measurement is still valid and fairly accurate. Vertical antennas which are excited against ground or radial wires can also be measured with the FA-VA5. If a coax connection is present, it's as simple as 1 2 3. Direct connection via suitable adapters and we are done. If the antenna wire is usually connected to a tuner, then we need to disconnect the antenna wire and insert a coax socket with the outer metal body of the socket firmly connected to the grounding terminal that is used during antenna operation. That ground connection must be as short as possible because otherwise it will falsify the measurement results because of its inductive reactance. Alternatively, I sometimes use a simple "BNC-male to banana" adapter for measurements are HF frequencies. A guiding principle should always be that an antenna is a "closed-loop circuit". By that is meant that for example a quarterwave vertical antenna extends from the radiator back to ground (or radials) via the electric near-field and on the ground, the RF current flows back to the feedpoint, thus forming a "closed-loop". This also implies that if we have a poor conductivity ground, the real-part of the antenna impedance increases. Whereas a thin quarterwave vertical antenna has an impedance of about 37 Ohms (half that of a halfwave dipole) the real-part of the impedance increases significantly if the ground is bad. Good luck 73 Dieter, VK3FFB

Hello group, I am considering purchasing a fa-va5. I will mainly use it for antenna and trap meaurements. But: since it is a one port device, is it posssible to do some measurements on low/high/band pass filters? Or do I need a 2 port device? Thanks for your advice Jeroen PF1JM

I've just found the correspondance about measuring CMR of CM filters, and the Impedance option menu(s). However I haven't been able to find advice for a test jig or connection method for doing CMR measurements. I thought I would have to acquire a VNWA3 to play with for these properties. Is there any information available, or can Someone send that to me please? Toys that continually make us think harder and harder hopefully keep Mr Alzheimer at bay! 73 , Peter