24-07-2024, 05:42 PM
You'd want several log periodics for 14 MHz to 40 MHz, one for 30 to 150 is large. And then 150 to 400, 400 to 1.2 GHz.
I've seen a big one on a USA embassy roof that looked like part of HF to low VHF.
The Band III only log periodics common here and Band III ended 2012.
10 KHz to 7 or 14 MHz better served by multiple loops.
An untuned HF loop is only good for a coarse wideband spectrum display. I had an HP 141T with 100MHz , 1 GHz and 10 GHz approx plugins. Replaced with a Rigol 9 kHz to 1.5GHz analyser with Tracking Gen (works as sig gen if span = 0). https://www.amazon.de/-/en/dp/B00CLWJA38 You do need to tune an HF loop for actual reception and it's simple.
At zero span you can use the Rigol as an AM or FM radio (has a headphone jack!) at 9kHz to 1.5 GHz. I could have bought the 3.5 GHz version, but it's nearly x2 price and I hardly need more than 450 MHz. Maybe 1.2GHz
Even to get one long wire rather than two working on 1.8 MHz to 30MHz with a match box (ATU) is tricky. Most will not tune (really match) 1/2 wave or integer multiple, though something around the 20m (but not electrically 20m) seems to work even at 50 MHz. I have a flagpole (if anyone asks) at the front gate and a long-wire to back of roof via plastic stand off on the chimney. I did have the remote FC-40 on the roof, but it's moved into the attic this week. However something has gone wrong with the home made vertical for 70MHz (4m) supposedly matched using a nanoVNA. It's working too well on 14 MHz to 50 MHz via FC-40 and about 5:1 on 70 MHz. I connected the VNA with rig on and used remote relay for whip, and the nano-VNA confirms that. So it needs examined. I suspect connection bad at base or connector and that the random coax to it is radiating.
I've seen a big one on a USA embassy roof that looked like part of HF to low VHF.
The Band III only log periodics common here and Band III ended 2012.
10 KHz to 7 or 14 MHz better served by multiple loops.
An untuned HF loop is only good for a coarse wideband spectrum display. I had an HP 141T with 100MHz , 1 GHz and 10 GHz approx plugins. Replaced with a Rigol 9 kHz to 1.5GHz analyser with Tracking Gen (works as sig gen if span = 0). https://www.amazon.de/-/en/dp/B00CLWJA38 You do need to tune an HF loop for actual reception and it's simple.
At zero span you can use the Rigol as an AM or FM radio (has a headphone jack!) at 9kHz to 1.5 GHz. I could have bought the 3.5 GHz version, but it's nearly x2 price and I hardly need more than 450 MHz. Maybe 1.2GHz
Even to get one long wire rather than two working on 1.8 MHz to 30MHz with a match box (ATU) is tricky. Most will not tune (really match) 1/2 wave or integer multiple, though something around the 20m (but not electrically 20m) seems to work even at 50 MHz. I have a flagpole (if anyone asks) at the front gate and a long-wire to back of roof via plastic stand off on the chimney. I did have the remote FC-40 on the roof, but it's moved into the attic this week. However something has gone wrong with the home made vertical for 70MHz (4m) supposedly matched using a nanoVNA. It's working too well on 14 MHz to 50 MHz via FC-40 and about 5:1 on 70 MHz. I connected the VNA with rig on and used remote relay for whip, and the nano-VNA confirms that. So it needs examined. I suspect connection bad at base or connector and that the random coax to it is radiating.
