It was great to see the tracking generator on this little filters. And terminating the filters in 50ohms, and then using just S11 of the nano was a total revelation. Thank you very very much!
Interesting, I do not see any attenuation of the second harmonic at 14.0 Mhz. Noting your reference point is at -10 dB, you have -9.75 dB near 7.0 Mhz and only -10 dB at 14.0 Mhz. I built the same kit and it is at -42 dB at 14.0 Mhz. At 28 Mhz you have -66 dB which looks very good.
Very good indeed. Looking forward to the next episode. The high SWR on the NanoVNA has (I think) answered a niggling question I have had for a long time. The question is "What happens to the rejected power of the low/band pass filter"? My first instinct was to say "it is dissipated as heat", But, of course, inductors and capacitors don't dissipate heat (not much anyway) - so I guess it must be reflected back to the source? - as the SWR shows. What do you think?
Ahahah man! We are/were on the same boat! When I started learning, I also though that the "rejected frequencies" were dissipated in heat. Instead, as you say, they are reflected! See my Episode 12 where I discuss this 'discovery' :) Generally speaking, ideal capacitors and inductors do not dissipate any energy in heat. They just store it in the electric/magnetic fields, respectively.
Definitely reflected back to the source and the output stage of the source heats up if the reflected power is high and can cause damage. This is a good video.
thanks Philip! I had to stop my hobby during summer 2020 due to other stuff to do, job etc, but I sure hope to come back to activity as soon as possible.
@@therfnoob7697 Since you seem to be very knowledgable, may I Just ask you if the job you mention or your education is related to rf electronics, or you did you really manage to learn it all on your own? And if so, how long did it take approximately? :)
@@lillykovar3265 hi! Not at all, I am a researcher in computer science, but the math side, not the physics/RF :) I really started from a simple arduino, my first ever exposure to electronics, and the built up the hobby slowly over the course of 3-4 years :)
Hello friend, I hope you are well, I want your advice, I am trying to amplify the small signal of a satlink ws6990 modulator, to transmit digital tv at 509 mhz, could you recommend any amplifier to achieve about 8 watts of power. Thank you
Hello. I like very much your video. You make clear and precise presentation of the subjects. And I'm an electronic engineer with experience in domain. I have a question not related to this video but I put it here because it's your last videos. You are familiar with portapack h2. It a good device ? I'd like to buy one. You know a good AliExpress shop where is ok to buy a product like this ? Thanks a lot.
Hi! Thanks I appreciate very much your comment :) Regarding a good store... I personally bought my portapack with Piswords, and I was happy: (piswords.aliexpress.com/store/829772?spm=a2g0s.9042311.0.0.27424c4dJpft4q) But my feeling is that many other stores are good, you just need to check that they have a lot of good comments.
Hi, I am watching your videos episode 62, 63 with big interests and wating of episode 64. Hope to see one time the tranmission of hackrf with your amplifiers, BPF, LPF and also the receiver. Any plan when ? Thanks a lot.
It was great to see the tracking generator on this little filters. And terminating the filters in 50ohms, and then using just S11 of the nano was a total revelation. Thank you very very much!
Interesting, I do not see any attenuation of the second harmonic at 14.0 Mhz. Noting your reference point is at -10 dB, you have -9.75 dB near 7.0 Mhz and only -10 dB at 14.0 Mhz. I built the same kit and it is at -42 dB at 14.0 Mhz.
At 28 Mhz you have -66 dB which looks very good.
Very good indeed. Looking forward to the next episode. The high SWR on the NanoVNA has (I think) answered a niggling question I have had for a long time. The question is "What happens to the rejected power of the low/band pass filter"? My first instinct was to say "it is dissipated as heat", But, of course, inductors and capacitors don't dissipate heat (not much anyway) - so I guess it must be reflected back to the source? - as the SWR shows. What do you think?
Ahahah man! We are/were on the same boat! When I started learning, I also though that the "rejected frequencies" were dissipated in heat. Instead, as you say, they are reflected! See my Episode 12 where I discuss this 'discovery' :)
Generally speaking, ideal capacitors and inductors do not dissipate any energy in heat. They just store it in the electric/magnetic fields, respectively.
Definitely reflected back to the source and the output stage of the source heats up if the reflected power is high and can cause damage.
This is a good video.
I hope you come back!
thanks Philip! I had to stop my hobby during summer 2020 due to other stuff to do, job etc, but I sure hope to come back to activity as soon as possible.
@@therfnoob7697 Great news!
@@therfnoob7697 Since you seem to be very knowledgable, may I Just ask you if the job you mention or your education is related to rf electronics, or you did you really manage to learn it all on your own? And if so, how long did it take approximately? :)
@@lillykovar3265 hi! Not at all, I am a researcher in computer science, but the math side, not the physics/RF :)
I really started from a simple arduino, my first ever exposure to electronics, and the built up the hobby slowly over the course of 3-4 years :)
@@therfnoob7697 Alright, cool. Hope you come back around to it soon then!
Hello friend, I hope you are well, I want your advice, I am trying to amplify the small signal of a satlink ws6990 modulator, to transmit digital tv at 509 mhz, could you recommend any amplifier to achieve about 8 watts of power. Thank you
Hello. I like very much your video. You make clear and precise presentation of the subjects. And I'm an electronic engineer with experience in domain. I have a question not related to this video but I put it here because it's your last videos. You are familiar with portapack h2. It a good device ? I'd like to buy one. You know a good AliExpress shop where is ok to buy a product like this ? Thanks a lot.
Hi! Thanks I appreciate very much your comment :)
Regarding a good store... I personally bought my portapack with Piswords, and I was happy: (piswords.aliexpress.com/store/829772?spm=a2g0s.9042311.0.0.27424c4dJpft4q)
But my feeling is that many other stores are good, you just need to check that they have a lot of good comments.
Hi, I am watching your videos episode 62, 63 with big interests and wating of episode 64. Hope to see one time the tranmission of hackrf with your amplifiers, BPF, LPF and also the receiver. Any plan when ? Thanks a lot.