Hi Mike, Saw this circuit in the first episode of your series on noise cancellation, and I built it in the next couple of days. It works a treat, and I would recommend it completely to anyone looking for a simple project which wll make so much difference to listening pleasure. Many thanks, and vy73 , Dave G0ELJ
Yes, I've built it since and can confirm that it works well. No battery required and most receivers have more than sufficient gain to make up for insertion losses. Thanks Mike.
Buried coax and ferrite beads are critical for the coax from the noise antenna, or at least a lot of ferrite beads. You have to make sure your noise source is coming from a single point in order for the phasing to work properly.
Thanks for showing your earlier passive canceller and testing it over a wide spectrum of frequencies. It's nice having a unit that doesn't require power to run it, sure there is some loss, but not that much. I might just have a go at making one up, I'm quite new to winding toroidal transformers and worried about getting my starts and finishes wound correctly.
I'm about 7 months late on replying, but these are broadband coupling and phasing transformers, not part of resonant LC circuits that require precise L and C values, so I think you could easily be off plus or minus a turn or two with no noticeable difference in the result. So just build it. The first thing an RF electronics hobbyist needs to learn is to just go ahead and try it and see if it works. If it works, great. If it doesn't, that's the time to dig in and figure out what you did wrong, or just toss it in the spare parts box for cannibalization for other projects. At these frequencies, most everything is very forgiving. You see the wide-open, long-lead construction of this unit, and it still performs famously.
Im try to learn about RF . Basic concepts.the " boy's fist book of radio..." was good.any sugestion to download some pdf of other ?.love this old books !!
Mike, I like experimenting and making simple AM radios using a ferrite rod antenna. Have you tried using this passive noise canceling circuit with a ferret rod antenna? I'm curious what your results might be. Thank you for your videos!
These is no reason why this would not work nicely with a ferrite rod and whip or simply, a pair of ferrite rods that you can rotate. Simply remove the primary windings altogether and wind on the Signal and Noise rods. 8 Inch long Rods like "LTKJ 5PCS Black MnZn Ferrite Rod Bar Loopstick for Radio Antenna". One reduces to a single winding and one to a center tapped winding. Try 20 Turns and 40 Turns Center Tapped for an untuned approach. Tuned would be a bit more complicated because you would need low Z secondaries. So the tuned side with 365 pF Variables would be 90T and the secondaries maybe 10T for the main and 20T Center tapped for the Noise Side.
Very impressive. That first station truly went from "what station" to intelligible.
Hi Mike, Saw this circuit in the first episode of your series on noise cancellation,
and I built it in the next couple of days. It works a treat, and I would recommend it
completely to anyone looking for a simple project which wll make so much
difference to listening pleasure. Many thanks, and vy73 , Dave G0ELJ
Yes, I've built it since and can confirm that it works well. No battery required and most receivers have more than sufficient gain to make up for insertion losses. Thanks Mike.
Buried coax and ferrite beads are critical for the coax from the noise antenna, or at least a lot of ferrite beads. You have to make sure your noise source is coming from a single point in order for the phasing to work properly.
Thanks for showing your earlier passive canceller and testing it over a wide spectrum of frequencies. It's nice having a unit that doesn't require power to run it, sure there is some loss, but not that much. I might just have a go at making one up, I'm quite new to winding toroidal transformers and worried about getting my starts and finishes wound correctly.
I'm about 7 months late on replying, but these are broadband coupling and phasing transformers, not part of resonant LC circuits that require precise L and C values, so I think you could easily be off plus or minus a turn or two with no noticeable difference in the result. So just build it. The first thing an RF electronics hobbyist needs to learn is to just go ahead and try it and see if it works. If it works, great. If it doesn't, that's the time to dig in and figure out what you did wrong, or just toss it in the spare parts box for cannibalization for other projects. At these frequencies, most everything is very forgiving. You see the wide-open, long-lead construction of this unit, and it still performs famously.
Definitely one for the project list!
That WJ-8711 looks somehow familiar...
Hey! Its broken.
I love passive modules.
(Always feels a bit like something for nothing. The "art" of course is to minimise the losses.)
Im try to learn about RF . Basic concepts.the " boy's fist book of radio..." was good.any sugestion to download some pdf of other ?.love this old books !!
Mike, I like experimenting and making simple AM radios using a ferrite rod antenna. Have you tried using this passive noise canceling circuit with a ferret rod antenna? I'm curious what your results might be. Thank you for your videos!
These is no reason why this would not work nicely with a ferrite rod and whip or simply, a pair of ferrite rods that you can rotate. Simply remove the primary windings altogether and wind on the Signal and Noise rods. 8 Inch long Rods like "LTKJ 5PCS Black MnZn Ferrite Rod Bar Loopstick for Radio Antenna". One reduces to a single winding and one to a center tapped winding. Try 20 Turns and 40 Turns Center Tapped for an untuned approach. Tuned would be a bit more complicated because you would need low Z secondaries. So the tuned side with 365 pF Variables would be 90T and the secondaries maybe 10T for the main and 20T Center tapped for the Noise Side.
That sounds great, thank you very much.
Great Mike, i always thought your original one worked great ! Good stuff, thanks , 73 Jerry
Great Work , as usual!
You do these vids only to show off that WJ-8711 occasionally. Just to make us drool (BTW - as I age I do that on my own). Thanx for the vids! 73
Market it.
Mike doesn't need the hassle... 🙄😂
Very very cool! Where can we get a schematic for it?
1. Go to 6:05;
2. Get a pencil and paper;
3. Copy;
4. Behold your schematic!
1. Got to 6:05;
2. Get a pencil and paper;
3. Draw;
4. Behold your schematic!
@@MirlitronOne too lazy. I’ll just screen shot it
Outstanding. Would be really cool if we could make it auto null .... a lot of extra circuit though. Love the simplicity and results! 73 - KF6IF
73