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Sean, Some of the issues I had with dipole mode was due to Common Mode noise. So, those ferrite torroids helped! If I remember correctly the only jumper (on amplifier board) I changed was the one that

Incidentally, Chavdar mentions jumpers for Dipole mode, I assumed that the switch between modes is all you need? Have you got a close up of all the jumpers set on your device? (as a sanity check)

Hi Simon, Thanks for the info. There is a lot to learn about noise, much of which I simply don't have the tools or instruments to do any real science with, however taking advice and applying some

Hi Sean, I went through similar issues last year. I also have AAA-1 from Chavdar. Here is one of the posts with Chavdar's recommendations: /g/loopantennas/message/19476 I use CAT8

Hi Fred, If I switch to dipole mode, I get an increase in SNR but the noise floor his higher too. Now I have the switch box made, I can do some more testing! Cheers Sean

Hi Fred, Ah! OK, thanks for that. Looks like I will be redoing the FTP cable - such a delightful job with Cat6a - tomorrows tinker time. How many turns you recommend? I think I have 4 on there now.

Sean, all used lines must be wound on the ferrite toroid, or must be choked with separate toroids.? It is not enough to have a common-mode choke in the RF-Feedline only. In this case common-mode

Hi Martin, Something like what I have done here: (the orange pair is the RF pair) /g/loopantennas/photo/302470/3917370?p=Created%2C%2C%2C20%2C2%2C0%2C0

What you might do is run just one loop for testing, then you can null out the strongest noise offenders with a simple azimuth change. The loop configured as you have it isn't going to be able to null

Hi Sean See lz1aq web site for details of cat5/6 common mode choke..its small in size..you use the inner cables, no screen, no outer. A fews caps and small ferrite and in an ip rated box Simon g0zen

Will do, I'm using KiwiSDR monitor to graph SNR across a few different ranges. So I will keep track of it once I have finished tinkering (I know, there is no such thing as "finish tinkering") Cheers

Hi Simon, I do intend to rebuild this at some stage with a new material, as the PVC pipe is possible a bit weak as the intersection point and a fairly strong wind is like going to break it, so will do

Hi Martin, Are you suggesting winding the cat6a through a ferrite core? I'm almost certain, to achieve this, I would need a ferrite the size of a dinner plate :-D It is double shielded, has aluminium

Keep us informed as to how well it works across it's Freq Range. ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?? Garey Wittich

Sorry Fred, The AAA-1C amplifier has two amplifiers: one low input impedance loop amplifier, and one high input impedance amplifier for dipole mode. In orthogonal configuration the two loops are

Simon, the AAA-1C has two independent loop amplifiers between which you can switch remotely. It is not two loops connected together. regards Fred

Sean Try the loop/ a loop with just one loop, ie not 2 at 90.. That way you can adjust loop direction for best nulling of local noise ( if mainly coming from 1 direction ( or 2 if at 180 to each

Even though the loop uses twisted pair network cable, and the amplifier & control boards have a decent amount of on-board filtering, it's still worthwhile adding yet more ferrite cored choke baluns on

Hi Fred, Thanks for the reply. The PSU is actually an iron core linear power supply - took me ages to find! I haven't tried switching modes. I don't have the switch built yet, I have just shorted the

Looks perfect. The poor SND might be a problem of a noisy environment. The antenna actually receives, what's in the air. The AAA-1C allows switching between magnetic loop mode and electric dipole