Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
Search
Notes on FA-VA 5 status
|
Dear FA-VA4/FA-VA5 users,
some of you discussed in the forum that the FA-VA 5 has discontinued. As the developer of the antenna analyzers I am happy to comment the current situation.? The exclusive manufacturing of the units was with German BOX73 = Funkamateur. After extending batches of units several times, they decided to stop the production in 2024. Even if there is still relevant demand, their decision reflects the current situation with price increase in components and shortages in components. The pandemic situation changed a lot in the semiconductor business. It is no secret that even today many components are double in price, compared to the situation before 2000. Besides the high prices, changing shortages are still a daily business. One day it is the controller, another day it is the TCXO, then there is a shortage on boost converters or displays and other components. It is quite challenging to test equivalent parts or even change the PCB from batch to batch. However, over the years, BOX73 kept a nearly stable price, potentially leading to decreased profit and additional efforts. I have to say, I can understand such decisions, as involved people have to run a business with a need for enough profit and income. That does not mean that the FA-VA 5 is old iron, it is still an attractive antenna analyzer with many sophisticated features. The goal was to provide a cost effective, accurate measurement unit for ham radio needs. From my perspective this goal has been achieved. The FA-VA 5 is an accurate and mobile device, has a simple but sunlight readable user interface and uses so less power, that batteries last for years. In contrast to user units, the internal mixers are highly resistant against electrostatic discharge. A strong test signal allows to perform antenna measurements even with nearby broadcast stations. For more stationery use cases, VNWA allows detailed one port analysis. Thousands of users enjoy the antenna analyzer and use it on a regular base. Please allow me to highlight the true team approach on the FA-VA 5. Besides my own contribution, Jan (G5BBL), Kurt (OZ7OU) and others provided major support for components, calibration standards and other topics, Tom (DG8SAQ) made it possible to use his sophisticated and comprehensive VNWA software and helped with discussing the mathematics. The result is a true ham radio product for ham radio users. Moving forward there are several options of which feasibility still has to be answered: 1. New production of FA-VA 5 batches with a different manufacturer. Maybe some small changes within a well defined scope. 2. A complete new design for an antenna analyzer, the VA 6, as a mobile unit. 3. A complete new design as a multiport mobile / stationery analyzer which allows enhanced measurements. Maybe we can start a discussion on this. I would be happy to get your thoughts. It is time for a wish-list. Especially for option 1. what would be the most needed changes to the FA-VA 5? For example, it should be quite easy to change the BNC-connector to an N-type connector. More buttons or even a membrane keyboard? Bluetooth connectivity? Some are asking for a TFT-color-display. As you can see, the move from option 1. to option 2. is very fast, as a sunlight readable TFT-display needs lots of power, which drives the need for Li Po-batteries etc. In addition, more RAM and another processor is needed. Happy to get your thoughts on the topic. Regards Michael, DG5MK |
开云体育Hi Michael:A few comments from this side of the ocean.? Let me start by explaining my use of the fa-va5.? I am primarily an HF guy (1-30MHz).? Second, I do a lot of work with transmission lines and some antennas.? I think my uses may be different than many others.? My suggestions do not reflect the practicality of implementing some of these features. So, to start... I would like to see a switch-selectable change between 50 & 75 ohms.? There could be 2 input connectors, one for 50 and the other for 75 ohms.? An F connectors is very often used over here for 75 ohms.? I would prefer an F connector rather than a BNC;? more on this reason in a minute.? For 50 ohms, I would like to see a UHF connector.? I am very aware of the limitations of UHF connectors, but once again, I'm an HF guys.? More important is the fact that I would prefer not to use an adapter.? I often travel with my fa-va5, and what happens if I forget or lose an adapter?? Could a new kit be designed that would allow the user to install either a UHF connector or something like an N connector? The display... keep it as it is.? I live in Florida and also spend a time in the Caribbean.? Bright sunlight is an on-going problem.? As for changing to a color display, in my opinion that's just an enhancement that does not necessarily add to the functionality.? In other words, just a bell and whistle. Changing batteries... I am not especially fond of this idea.? I do not like the idea of some external battery charger.? You have to worry about having the correct ac plug for the charger.? In October I am going to a country that uses European ac outlets.? I'd rather carry extra batteries than worry about the correct plug on a power cord. New functionality... How about adding a TDR function?? How about a way to measure transmission line loss without having to use the open/short technique?? I seems to remember some analyzer having this capability.? I frequent a Caribbean contest station where we have feed lines for our receive array that are 250-300 meters long.? We have to install these feedlines for each contest.? We'd like to have a "quick and dirty" means to measure feedline (50 & 75 ohms) loss after the lines are rolled out.? The open/short method will work, but it takes 2 people and some other logistics. Please keep the functionality that allows use of the DG8SAQ software.? I also use that device. Bluetooth... not high on my list.? I just think it's another bell or whistle. Keep the VA6 functional and independent of other external bits and pieces like adapters that you will lose or forget. Last thing... I do like the idea of switch selectable bands.? 73 charlie, k1xx On 5/29/2024 8:44 AM, Michael DG5MK
FA-VA5 creator wrote:
Dear FA-VA4/FA-VA5 users, |
|
Hi Charlie, |
|
One item of the VA5 that really needs improvement is the On/Off switch. The one in all the units I have bought for myself or for other people has proved to be 'touchy' at best, and intermittent as time goes by and wear increases. A quicker scan rate could be useful, if this doesn't affect battery life too much. And standard, replaceable batteries in the VA5 are a real benefit. One doesn't need to worry about keeping the VA5 in carry-on baggage when travelling by aircraft. Or air-freighting the unit. |
Either one has my vote provided the mass of the new variant does not increase.? I like the fact the connector is mechanically attached to the enclosure and not the pc board.
This jostled the memory and reminded me I needed to check the batteries. Any device I own I now remove the carbon-zinc or alkaline cells due to the risk of leakage. Whatever choice you select, please pick one that minimizes the risk of damage that accompanies the generic AA and similarly constructed cells. Also, if some method can be implemented to limit lateral forces applied to the proposed USB-C connector, it would be greatly welcomed by this old goat. USB-C is ok on cell phones, but devices with more mass and prone to being dropped, I find the USB-C to be just as susceptible to tearing from the PC board with the abrupt lateral jerking that frequently occurs.? Thank you for asking for end user input. Regards Chuck WD4HXG |
开云体育I knew when I made my suggestion regarding changing to a UHF connector that I'd get push back from some folks.? I also tried to qualify my use as being HF oriented as well as a lot of use in the field.? I would dare say that if you want to connect to the antennas/feedlines of today's amateurs, >95% would be UHF connectors.? There's a place for other connectors in other situations and geographical locations.? Even that all purpose TNC (?).Recently there was an email on another reflector that showed prior testing results for UHF connectors.? If you want to read the full email, it was sent by Kimo Chun on the Tower Talk reflector on 6/17/2024 at 12:53 PM.? The original testing results were published by K7FR in the 1996 time frame.? Some of the results were: f (MHz) Loss (W) dB 0.1 1 -0.00435 1 1.2 -0.00521 10 1.3 -0.00565 20 1.5 -0.00652 30 1.8 -0.00782 50 2.2 -0.00957 100 2.6 -0.01131 200 3.5 -0.01523 300 5 -0.02177 400 7 -0.03051 500 10 -0.04365 1000 15 -0.06564 1250 18 -0.07889 1500 28 -0.12334 1750 39 -0.17277** 2000 100 -0.45757** ** Connector failed before calorimeter stabilized. When testing in the field, I can live with a UHF connector and that bump in impedance. Sure beats forgetting that all important adapter. In a somewhat static environment on the bench at home, almost any connector will suffice if it fits your test situation and environment. If a new FA-6 came out with an N connector, I'd be looking to swap it out for a UHF connector. But again, that's me. 73 charlie, k1xx On 6/30/2024 10:40 AM, Chuck WD4HXG via
groups.io wrote:
|
to navigate to use esc to dismiss