Noise Cancellation Part 2

Lets look at building a Noise Antenna and Investigate some Building Blocks so we can design an effective Antenna Noise Canceller for the Shortwave Bands.

[@Steve-GM0HUU]

Bored to death? Never. Really appreciate video and all the background information. Looking forward to next installment, as I would like to build one of these devices. One concern I have is that it, if used with a transciever, it would be nice/sensible to autobypass the RX noise reducer on TX. I know I could use a manual switch. However, I also know that I shall probably forget to switch and fry the noise reducer.

[@andersonnobre5163]

Thank you for this smart noise combat! Here in Brazil we have great problems with electric noises to led lamps .73!

[@KingLoopie1]

Not bored, but feeling like I need further study to catch all that you're saying. Other than my own fog, it looks like something I want to build! 👍

[@MirlitronOne]

Hi Mike, looking forward to part 3, de M1GWZ.

[@sincerelyyours7538]

Very interesting! Looking forward to getting some HF bands back that are completely useless in my area due to noise. This should be fun!

[@Chris_Grossman]

Very nice. I like seeing the combiner examples. I am used to seeing on-chip transmission line circuits. It’s nice to see things I can do in my garage.

[@channelview8854]

Great stuff! Thanks.

[@alainmichaud8992]

Wow! As mentioned by previous comments, the power combiner section is really really good. You have a lot of experience because one does not find a description for those very often in textbooks! Can I just add some more noise to this: They call this "noise canceller" but it really only cancel man-made interference. What the "canceller" does really is to put a notch in the directivity pattern. The real noise or (thermal/Johnson) "frying pan" noise does not go away. The best thing you can do for this one is to avoid any losses (before the first amplifier). In my receiver, I have a LOT of frying pan noise. My initial thought was that I should use a tuned antenna? Tuning an antenna at a distance is not fun. I mean it is counter productive to put a 50 KHz antenna in front of a 30 MHz receiver! I digress. Finally, back to the couplers: They are used to combine the output of several RF transistors in order get a high power output (as well as a push-pull action). A while ago, you briefly showed a "classic" circuit diagram. It would be very very interesting to hear you talk about that design. I understand this is no beginner stuff and it may not fit to this channel. But since you are the expert... That was a great video. Thank you again.

[@MIKROWAVE1]

Wow! I agree that a major contributor to noise cancellation is due to spatial beamforming, but not that it is the only effect in play. Certainly putting some selectivity up front, especially with the SDR front ends which are fairly wide, even for so called "narrowband SDRs" has to help as proven with the R390 where selectivity is put in every place possible in the tuning chain.

[@Tony770jr]

I could use this for regenerative tube receiver. Thanks!

[@tubeDude48]

Very informative, Mike!

[@nigelbrockwell6237]

Thanks, very informative video.

[@JimSky]

I have never had much luck with my MFJ-1025 - I'm going to try your passive circuit next. I love your channel BTW. The Morgan series was fantastic. Its all great, really. You really deserve to be in that new QST column. TNX es 73 de KH6SKY

[@MIKROWAVE1]

KZbin does not reward these types of channels. They do not promote info-oriented niche-type content. But it gets the stuff out there fast for the guys who are actively looking for new areas to explore in the hobby.

[@PapasDino]

Mike - wonder if you'd consider doing a tutorial on winding toroids with multiple leads, especially taking phasing dots into consideration...I have to go back to basics every time one comes along and I still manage to confuse myself...there must be an easy way to keep the phasing straight! TNX for considering...73 - Dino KLØS

[@W1RMD]

W2AEW is also a great source of information on this subject.

[@-Todays-Tom-Sawyer-]

Great Mike. Looking forward to killing my S9 noise floor here in OC California.

[@larryb728]

Hi Mike, thanks for your great instructional videos. I am currently working on what I thought would be a simple project, a preselector for my SDRUNO receiver but I am a little confused. There are series, parallel, T arrangements etc. Using a parallel circuit my circuit act more as a notch filter than anything else. Could you possibly de-mystify tuners, preselectors or impedance matchers?

[@clytle374]

Skipped over these noise videos at first due to finally getting my first antenna built(and being very sick of antenna work) and getting my first contact. Bands are dead as a hammer, so watching along. Any chance of nulling out static crashes from lightening this way?

[@albertodelrio9206]

Es lo mismo ferrite 43 o 61 ?

[@ameester1959]

can i get the schematic and info about the coils??

[@andersonnobre5163]

I AM a BRAZILIAN electronic