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It's not quite what you want but the old HP 4800A Vector Impedance Meter does 5 Hz to 550 kHz. Manual (as in 'hand operated') sweeping though! DaveB, NZ

Neil, The HP3577A VNA with HP35676A test set covers from 5Hz to 200MHz. Only weighs about 70lb. Some versions of the NanoVNA-H4 firmware work down to 800Hz (I don't know how well). I don't know if

Hi Frank, I'm a huge fan of yours, and very grateful for your countless contributions that continue to elevate the hobby. Many many thanks! Yes, I counted your suggestion of two 1/4-wave sections of

Dave forgot to model what is likely to be the broadest bandwidth solution using coaxial cable: Two 90 degree lengths of 75 ohm coax in parallel 73 Frank W3LPL

To Bill WA2WIO: You received several good suggestions on how to transform 25 ohms to 50 ohms. Here are a few more ideas that use only coax. Method 1: Connect a 70.0 degree length of 50-ohm coax to

Good morning, y'all. There is a fundamental feature of the physics involved in this particular antenna installation. No ground plane indicates a colinear antenna. But, the issue is, from the radio,

Is there any practical way to make a VNA that provides the same measurements over the frequency range of ~10 Hz to maybe 1 MHz? Is that something that could be done with computer or cellphone

k3eui. Barry; Dipole is center fed 1/2 wave 66ft #18 stranded insulated in a rt angle horizontal V. The shape is necessitated by the complicated and crowded attic construction. Interesting idea. I

Using a NanoVNA or a MFJ 259 either is the source of the RF... whereas using a transmitter then a short length of coax to a SWR bridge, changes the length of the source of RF to the antenna.. Larry

Yes, the coax is understood to be part of the antenna so an external meter would have to be at the coax end and not the antenna feed point. Also, Firestik says not to trim the length as it is factory

Perhaps my ignorance is showing, but It occurred to me that the linked "documentation", http://www.firestik.com/Catalog/NGP_3-Way.htm, makes it fairly clear why the Firestick NGP is named as such,

I have a MUCH MUCH less messy solution. Is the dipole (center fed) 130 ft (80m) or 66 ft (40m) or 33 ft (20m)? Center feds will work on the 3rd harmonic, so a 40m can also tune to 15m. So…. try

Actually the firestick NGP does indeed time at the antenna, and it does use the coax as a counterpoise. It does not use the vehicle as ground plane. I have one on a fiberglass bodied vehicle and used

Hello, The Firestick NGP is a mobile CB antenna designed to be mounted on a vehicle. That is why it has NO radials. The vehicle is supposed to make up the ground plane, not the coaxial lead. Without

I'm using a NGP antenna in a camper for reasons. While an in-line SWR meter can cause issues, the VNA is the perfect tool for tuning. Got mine tuned to over 30dB return loss. Chris

Hi all It seems there is only 9 vertical graduation lines on the 4'' H4 version , if it can be configured to 11 graduations as with 4'' F version ?? 73's Nizar

These "No Ground" antennas use the coax feeding it or the ground connections to the radio as the counterpoise to the radiating element hence the recommendation to use the radio's SWR meter. I would

Its a proprietary cable and not just something like a make shift sleeve dipole. The shield isn't connected at the antenna side. Maybe it's somehow a J-pole using the coax?? I fail to understand

Sure sounds like the length of coax is part of the antenna matching.Especially true for an antenna without radials or a ground plane. So that extra length of coax between the radio and the SWR