Thanks for watching!

Thanks 👍

Thank you! Cheers!

Glad you liked it!

Go for it, It is not as good as the 80M version but it works. :)

@@mike-M0MSN I already built a 20-10 loop but want one for 40 meters. Wondering how many watts you can run on your 40m loop?

Many thanks!

Please do!

I hope so too!

Thank you! Cheers!

Take a look at the 80 metre version

Great suggestion!

Thanks!

Rarely (never) is a pre-amp required on 40m, and pre-amps amplify the noise and the signal - they don’t improve SNR. Most people who work 40m a lot use attenuation on 40m and adjust the gain so signals are just a bit louder than the noise level. Pre-amps are typically only needed on 15, 10 and 6m- and only if there isn’t noise. There is a reason for attenuators, and he’s using it properly.

@@kd8opi all of what you said is entirely accurate, except for the fact that he’s using an unamplified magnetic loop-where using a preamp (and not an attenuator) makes perfect sense. You are losing dynamic range by driving a passive loop’s small signal beneath the noise floor of your rig. Remember that he’s about 20db down on receive (when properly tuned) from a dipole or loop. Adding an attenuator to that means that he’s about 30db down in total. In an ITU rural situation, that would imply a -140dbm noise floor. The TS-990 sensitivity is about -125dbm without the attenuator on, and about -115dbm with it on. Does that make sense?

@@philjensen5151 Um, no. For simple reasons. Look at his s-meter. He’s nowhere near a a -125 dbm noise floor, he’s at S3 noise WITH the attenuator on, probably S5 or worse with it off. That’s the problem with using ideal numbers in terms of receiving sensitivity. They essentially do not reflect reality, and represent theoretical lab generated data. I would might with you if his S-meter read 0-1, but it doesn’t. His noise floor is probably around -90 dbm, and he’s nowhere close to driving his rig beneath his noise floor.

@@kd8opi I'd have a hard time making the assumptions that you are making without putting the antenna on a spectrum analyzer, or one with a calibrated signal meter. I use an Icom R-8600 to make my measurements (or an RTSA). I wouldn't put money on the 990's S-meter being anywhere remotely linear below -100dbm, but that's just me. 73 de N4PAJ.

@@philjensen5151 The thing is Phil, if you look at the 990’s manual, they’re pretty insistent that their S9 level is -81dbm, and their S3 on 40 meters translates 100 dbm. As buggy as it is, its the only meter we have on his noise floor. Attenuation can be anywhere between 6 and 18 dbm. . He may be looking at a “true” noise floor of -94 dbm, with only 6 dbm (S5), or as high S9 with 18 dbm attenuation. Conversely, turning on his pre-amp gives you 6-18 dbm of amplification. I just done see how his S/N ratio can improve by pre-amping his background noise anywhere between s5 and s8. There just isn’t that much dynamic range left at that point. He just isn’t anywhere near the theoretical noise floor of his receiver. Almost nobody is on 40m, and it’s why pre-amps are almost universally discouraged on 40, 80, and 160 (even 20m is iffy). God forbid you have a thunderstorm w/in 300 miles, the crashes would be unbearable.

Hi Ian thank you , and nice idea...

In the next video... about a weeks time

Like all loops this is an inductor and the spacing helps calculate the loops inductance and so the needed capacitor, ;)

Both I have to test it properly but if the 80m one is anything to go by......

No Idea Pat, but I would say yes.

0:55

www.nonstopsystems.com/radio/antennas_home.htm

Thank you!

5mm spacers 1mm plates 2mm between each plate

Thanks Mike

yes you can

@@mike-M0MSN Thanks dear..

yes ish