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Hi Matt Sounds good. Here is some advice regarding the measurement of traps. I have used this method successfully when I made a trapped dipole for 18 and 14 MHz. When measuring a trap, we have to consider that a trap is a parallel-tuned circuit. *It is therefore not advisable to measure traps directly with the FA-VA5*. Any small amount of capacitance will falsify the measurement. I found the best way to measure traps is by using the FA-VA5 like we would use a Dip-meter. We can do this by setting the FA-VA5 to VSWR sweep mode with a narrow sweep width of say 1..2 MHz. You may need to refer to the manual (pages 15 to 17). Then we connect a suitable one or two-winding coupling coil made from solid wire to the FA-VA5 BNC socket. Coil diameter is not critical and should suit the trap coil. The idea is to couple loosely to the trap and observe a small VSWR dip in the VSWR graph at coil resonance. In order to obtain best results, the weakest coupling that still gives a visible VSWR dip will ensure highest accuracy. The marker function may come in very handy. Keep in mind that during marker adjustment, the FA-VA5 does not make new measurements ! This worked rather well here and I found very good agreement with a measurement made with my boat-anchor Agilent 8753 analyser. During trap measurement, the trap should be placed far away from any metal. You can support it with non-metallic supports. If the above is not entirely clear, please let me know. 73 Dieter, VK3FFB

Hi Maybe some of you have used the FA-VA5 for measuring coil "inductance" using the LCR meter function. Maybe you made a trap coil or a loading coil and want to measure it. If you have used the LCR function, then maybe you have encountered what may look like anomalies or mysteries. Perhaps you noticed that for some coils the inductance value changes with frequency. In standard circuit theory, however, the inductance "L" of an ideal inductance is a constant with the unit Henries (mH, uH, nH). Practical inductances possess a so-called winding capacitance. At higher frequencies they may even exhibit higher order properties. Winding capacitance acts like a small lumped capacitor in parallel connection with the coil. While at low frequencies the effect of the coil capacitance may be hardly or not noticeable, it rises slowly and becomes very significant when we move towards the parallel resonance frequency of the coil inductance and the winding capacitance. We first notice this when we measure a coil and increase the FA-VA5 frequency. The displayed inductance value "L" increases slowly with frequency as a consequence of the winding capacitance. If this subject is of some general interest and you would like to learn more, I am happy to elaborate more. For the time being, I end here. vy 73 Dieter, VK3FFB

I would suggest to Michael DG5MK a new feature, if is possible to add a sweep generator function, with these parameters: - start/stop frequency - number of points - sweep time I think it's not too much difficult to implement in the firmware, it is like an SWR sweep without RL measurement.

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