cheap ebay antenna analyzers

[nomadradio]

Bought one of these with the express plan to sort through the 455 kHz ceramic filters in stock. Pretty sure I have to put a resistor equal to the filter's input and output impedance on each side of it. Isn't meant to match a 50 ohm source or load.

Still haven't gotten that magic "round tuit".

73

 

[RT431]

Still haven't gotten that magic "round tuit".



I see what you did there.

 

[Mudfoot]

Wonder what tuner it is? 10 years? Would have to be an LDG, MFJ or Palstar. I suppose it could also be an internal auto tuner in a radio.

 

[Mudfoot]

https://www.rudiswiki.de/wiki9/nanoVNA

 

[Mudfoot]

Nice little demo board. Those UFL connectors won't survive repeated disconnects. SMB connectors or similar would hold up better

https://www.passion-radio.com/meter/vna-test-946.html

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/153776932292

 

[Mudfoot]

This thing is so tiny and the edges are sharp and rough. It's hard to hold. I just bought one of these 3D printed cases. It should fit the hand better. Even has a tiny compartment to hold calibration pieces. The plans are available free if you have a printer. I don't know anyone that has one.

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/174039026524

 

[Mudfoot]

HomerBB....

I played around with the software tonight. The interface is quite simple. It is much easier inputting whatever frequency span you wish. The measuring format has a pull down dialog box where you can quickly choose the chart format. I also discovered that there are different firmware versions that let you choose whatever parameters you want it to function as. I haven't download it yet, but one version turns the device into antenna analyzer mode. It eliminates everything else that you don't need, so it removes unnecessary clutter.

The software allows to input different calibrations. The device only allows storage of 5 profiles, whereas the software let's you save however many you want. I'm setting up different saved ranges. Like, HF, VHF and so forth. When using the software you don't need to touch the device except to turn it on and connect/disconnect whatever antenna. I'm far from an expert, but I'm somewhat getting the hang of it. I'm going to load up each FW and play with them.

 

[HomerBB]

Sounds promising.
I would enjoy a more streamlined GUI.
I will have to figure out how to change firmware to get my unit there.
Thanks

 

[Mudfoot]

There are several firmware designers. Two of them are the original designers. There are two firmware file types. Hex and DFU. The firmware on my device is a Hex file. The software that uploads the FW has a utility that will convert each one to the other.

I've loaded several different FW versions. All of them have more features that are very handy. When you first upgrade, you have to short two pins that put the device in upgrade mode. The newer FW versions add a feature that adds a software option that puts the device in FW mode. This makes uploading new firmware much easier.

Certain versions have two and four channels. I'm currently running two channel. The version I'm using make it more of a traditional antenna analyzer. There are versions that add TDR functionality and adds 1.5 gig measuring ability. The 1.5 gig utilizes the 3rd harmonic. I imagine it provides ball park results, but is still useful.

So far, the latest versions have improved the calibration procedures to make it much more accurate. The actual technique to upgrade is very easy and involves just a few clicks of the software. I recommend subscribing to the group.io forum. This group is where all the action is.

 

[Mudfoot]

The following link has all of the firmware from different developers. I have the latest version from Larry Rothman. This version includes larger font, which definitely helps.

https://oristopo.github.io/nVhelp/html/firmware.htm

 

[Mudfoot]

Received my 3D printed case. I had to dremel it in a few place to get it to fit. Nothing to difficult, but it does help to hold it and provide protection. It has a little compartment that holds the calibration standards.

 

[Mudfoot]

If anyone else got one of these, I'd be interested in how you feel about it.

 

[Mudfoot]

http://www.randl.com/shop/catalog/product_info.php?products_id=75127

 

[CB590]

I just ordered the Aursinc (upgraded) from Amzn for $80 in the newer style case with 3.4 Firmware. Supposedly does upto 1.5ghz.

since I'm moving I really don't want to have to go up and down my ladder 9 billion x.

mainly want for SWR for the darn A99 and check my end fed for SWR dips as well for 80/40/20m.

Will put up pics when I get in hand. Paid for 2 days shipping. Should be here Wednesday

 

[CB590]

Got my A99 back up at new location. 20' to the feed point and about 37' to the tip.

Was at this 1.49 when I started. Ended at 1.27 or so. Good enough A99 on 10' of pipe is kinda a pita when standing on a roof to go up an down.

got a radio check on 19. And my crossnedel read the same. So here to hoping.