Monday, July 16, 2018

FA-VA5 antenna analyzer received, built

I received my FA-VA5 in the mail today after a week-long delay in Chicago. Customs? USPS? Interference from Putin? Who knows, but it arrived today and went together in just under an hour.

The FA-VA5 is almost identical to the FA-VA4 that it replaced. The main difference in construction are the new analyzer's USB jack and the use of a cardboard spacer used when installing/soldering header pins.

The USB jack's small circuit board is insulated from the main board by an almost-transparent mica insulator. The circuit board is then soldered to the main board by flowing solder across 16 pads to their corresponding pads on the main board. Be sure that each pad has a solder bridge to its corresponding pad and that no unintentional bridges exist between adjacent pads.

A small cardboard strip is included in the kit. I threw it out thinking it was part of the packing material. After reading the instructions (and retrieving the cardboard from the wastebasket) I was able to install the headers that connect the main board with the display.

At my own choice, no manual was included with my kit - I opted to forgo the two-week waiting period for them to be printed since a pdf of the manual is available online.

Nothing in the instructions mentions the orientation of the three pushbutton switches in relation to the circuit board. There are 4 pins on each switch and 4 holes for each switch in the board - and the switch's pins will fit into the board in any way they're rotated. Upon closer inspection, I could just barely see how they might be meant to go in this way instead of that way and, taking a leap of faith, flowed the solder.

Either I was right and put them in correctly or it doesn't matter how they're oriented - the analyzer worked on power-up.

Here are a few photos of the kit:
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As it arrived
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German designed, English documentation - Ich weis das zu schätzen!

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The complete kit - not shown (but included) are the BNC calibrating terminations
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USB circuit board next to main board. The mica insulator can be seen in place on the main board

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Solder bridges - intentional ones! - are used to connect the two boards

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Owner callsign and a clock are new to the FA-VA5. An uncalibrated look at my Yagi on 20m.

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9 comments:

  1. Thank you John for posting. I am waiting for arriving my kit too... Aug shipping unfortunately...:)

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  2. The new FA-VA5 model goes to 600 MHz while the older model, FA-VA4 only went to 100 MHz. This certainly benefits the VHF/UHF crowd. The relatively small increase in price seems worthwhile

    73

    Steve Silverman KB3SII ... .. ..

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    1. I like it a lot. The sacrifice you make for the low price is that accessing the menus takes a bit longer than with the RigExpert analyzers due to having only 3 buttons. I like it despite that because of its light weight and small size with accuracy not being compromised.

      73 - John

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    2. Thanks for your review. I ordered this kit after reading it and so far it has been great!

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  3. I bought one, and have been exploring the differences in measurements made following calibration with the standard cal kit (supplied with the unit) versus measurements made following calibration with the "high accuracy" cal kit (available separately at additional cost). I found that the standard cal kit will produce measurements very similar to the high accuracy cal kit across the full frequency range if you enter the following cal model values for the standard kit:
    Open delay: -99 ps
    Short delay: -284 ps
    Load: R = 50 (or use a precisely-measured resistance for yours), L = 4.9 nH, C = 0 fF, delay = -151 ps.

    Assemble the short and open per the photos and instructions on page 37 of the manual. For consistency, when building the short, at steps 6 and 7, keep the wire coaxial (centered) in the body of the connector up to the back end where the bend is formed. After soldering, the main length of the wire should be centered.

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  4. I agonized over the switch orientation too. I finally determined that it doesn't matter as their function seems to be only to take three traces to ground when the respective switch is pressed. After a false start where I actually removed one switch I figured it out. In fact, I only soldered two pins per switch, the grounded one and the opposite one that connects to the active trace.

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  5. Hello all, Just completed the FA-VA5 analyser, however, while there is a polarity mark on the buzzer, there is no mark on the PCB. Which way is the correct polarity ???
    George G4EUF.

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  6. According to the manual (burried quite deep), it is +ve towards the battery cases - mine certainly bleeps that way - David G3XZP

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  7. Interested in the older VA4 if available but their website
    seems to be down. Been checking for a while?
    Any info/help K3VA

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