Our email service is still down. It looks like a major problem at Fasthosts. It anyone needs to contact us please use the alternative email address g4hyg@... Regards, Chris

We lost our incoming email service around 7 pm yesterday evening. We are not receiving any emails but can still send emails out as we uses a separate service for that. Regards, Chris

OK, Paul. PM sent and replacement head unit being shipped out today. Regards, Chris

Hi Keith, Good to hear that you like the LAA+. I had a quick listen to your Kiwi SDR and your antenna is working well. I'm not in the workshop so I don't have detailed figures to hand but I think that

Hi Jakko, 1 mm copper wire will work OK. The prototype I built uses the 1 mm wire I supply with the LAA+. A 80 cm loop will work well as a cardioid loop. Regards, Chris

Hi Gerard, The cardioid loop will work with the VLF version of the Loop Antenna Amplifier. A triangular loop will be OK as long as the resistor is directly opposite the feed point. The 110 ohm resisto

Recently I've been working on using a Loop Antenna Amplifier + to make a cardioid loop antenna. I've already posted a few comments about it in one of the recent topics. I've now written it up as a new

I should get the web page detailing the cardioid loop finished tomorrow evening UK time. I'll confirm if a short counterpoise works tomorrow. The improvement in signal to noise ratio over a convention

I hadn't spotted that that reply was going to the group. Here's a tidier version of the cardioid loop polar diagram I measured today: I'm working on a web page to show how to make a cardioid loop usin

Hi Simon, I plotted the antenna pattern today. I used a strong medium wave station in ground wave range as a source and turned the antenna making signal measurements every 20 degrees. Results on 160m

I only made front to back measurements today. I'll measure the polar diagram on a local medium wave station tomorrow. Regards, Chris

OK a bit of detail for you, I'll leave the detailed description of how it works for the web page, in very basic terms its a loop antenna and sense antenna in one. It's using a purple hulahoop to hold

OK, here's a photo of the prototype...

I did some work with the 4NEC2 antenna modelling tool to optimise the values for a cardioid loop using a Loop Antenna Amplifier +. This afternoon I built a prototype and mounted it on the 4.5m carbon

Hi Paul, I'm building a new batch so we can ship you one to arrive before the weekend. On recent batches I've replaced the twin diodes on the bias-tee or base unit output with one of the RF protection

Hi Kris, The Loop Antenna Amplifier + has a common mode choke on the output of the amplifier to stop RF noise on the feeder getting to the amplifier. It's OK to add another one at any point on the fee

I'll do some more work on it this week to measure the optimum values for the cardioid loop using a Loop Antenna Amplifier +. Once I've done that I'll post the loop design on this forum and make a YouT

Hi Simon. There are two ways you could improve your loop antenna system. The first would be to elevate the loop above the local clutter (houses, trees,etc). This will increase the signal levels but al

A 43 material toroid has the same permeability but it has slightly higher loss and doesn't have the epoxy insulating coating of the Ferroxcube toroid. Regards, Chris

That's an old review from Radio User magazine. We stopped manufacturing that antenna earlier this year. Regards, Chris