G8JNJ

OK - if that's a problem you need to use much bigger value capacitors :-)

Regards,

Martin - G8JNJ

I think you could either center tap the input transformer on the loop side (prefered method), or add two 1K Ohm value resistors (or similar) from either side of the loop / transformer connection to ground.

Regards,

Martin - G8JNJ

My guess is that you have inadvertently scraped some of the enamel insulation off the transformer winding(s) at some point, as it's very easy to do this.

I use Kynar insulated wire (the type sold for wire wrapping) wherever possible, as this is much more resilient. However this doesn't work with very small cores, as the wire is too thick, so in this case I just have to be extra careful when pulling the enamelled wire through the holes in the core.

Regards,

Martin - G8JNJ

The LZ1AQ loop amplifier kit uses CAT6 for power, control and signal.

CAT 5 & 6 has a characteristic impedance of 100 Ohms per twisted pair. You can build an impedance matching balun or use two pairs connected in parallel and a 1:1 balun. However if you use this method beware, as some CAT cables use different numbers of 'twists per inch' on the different cable pairs in order to reduce cross talk between pairs. This results in some pairs being electrically 'longer' than others., which may cause problems if you connect them in parallel to halve the impedance.

Regards,

Martin - G8JNJ

I've now spent a bit more time playing with this application.

It's not the easiest thing to setup or initially use, but it does have some quite impressive features such as the ability to import various online databases and parse .xlsx files such as the 'Numbers and Oddities' and 'ITU monitoring' databases into a set of local databases that can be searched, sorted and indexed.

When driving a local radio or the Twente WEB SDR (or others of that type) it's very handy for click tuning, ID'ing or scheduling stations.

Definitely worth spending a bit of time with to get the hang of it, plus it incorporates some really good ideas and useful features.

Regards,

Martin - G8JNJ