HAM RADIO: L Network build impedance matching Part 2.

[@rivit90]

Reinforcing my previous comments superb 2 videos mike really enjoyed them both , Went to a radio rally yesterday and came back with a very large high quality 500pf variable air capacitor and a decent quality 25-30 coil roller inductor with the intention of building my first basic antenna tuner , Ive watched a few videos and read a few articles on the subject, Yours nailed it for me , The maths bit was over my head a bit , but the construction and wiring explanation has given me the confidence to steam in cheers 👍

[@joeblow8593]

Greetings from across the pond and congratulations on 10,000 subscribers

[@mike-M0MSN]

Awesome thank you!

[@wfwtheradioguy3414]

Nicely done Mike, I stayed awake AND I learned a thing or two..... that's a win in my book.

[@BobHolowenko]

Glad to be part of the first 10K! Really enjoy the content sir!!

[@mike-M0MSN]

👍

[@sarto7bellys]

Stayed awake all week for this now time for a kip 😃 thanks for posting

[@mike-M0MSN]

No problem 👍

[@Locksnut]

Excellent setup and test Mike. Thanks. 73

[@mike-M0MSN]

Many thanks!

[@M7XCB]

Very interesting experimental work. Great video

[@richardwhitcroftkc3rrw63]

very interesting mike!!!

[@chrisbartlett6022]

Very interesting thank you Mike. Great couple of videos.

[@shakymedia_UK]

Brilliant video Mike. Like you I love playing with antennas. You explain it so well. Keep up the good work. 73s John GM0MST

[@mike-M0MSN]

Many thanks!

[@mikakb9519]

Thank you for the followup. Much appreciated.

[@mike-M0MSN]

No problem 👍

[@dennispeake1877]

Mike, thanks for all the effort you have put into this project, and sharing your Math's in the -J & +J that has always been my down fall to understand how that works. Good luck with your next project. God Bless you and your family. Cheers from sunny Queensland Australia.

[@johnwilson8229]

Another great video

[@mike-M0MSN]

Thanks again!

[@markramsay6399]

A great video. Learned a lot . Mark 2E0MSR (formally M7MSR).

[@mike-M0MSN]

Glad you enjoyed it, BTW well done on the 2E0 :)

[@rivit90]

just watched both videos , very informative and easy to understand , absolutely superb cheers mike ,,Ive been following your channel since the first lockdowns , Love your approach to projects .No expensive tools or items out of reach for most . Keep up the fantastic work and wishing you and family a great christmas tony M7TON

[@mike-M0MSN]

Cheers Tony

[@electro9480]

My opinion is a very excellent video, thanks.

[@acestudioscouk-Ace-G0ACE]

Good work Mike and well deserved congrats on your 10K! A lot of useful in your video, I'll have to watch it a few times to allow it to sink in to my geriatric brain.

[@mike-M0MSN]

lol

[@johnrees44..G4EIJ]

Thank you so much for the time and effort put in to make these interesting and informative videos..73..John..G4EIJ

[@pc4ad]

Oh no, it continues! :)

[@madcarew5168]

Nice build..I've a "joy match" atu. Ever heard of it.."not a lot of people know that!" Cheers 73

[@mike-M0MSN]

I can't say I have please give more info.. :)

[@madcarew5168]

@@mike-M0MSN all I know it's an L match apparently to be used with Joymatch longwire antennas from long ago and far away! Used it occasionally with success,now it sits on the shelf but not redundant.made by Partridge Electronics..Broadstairs..Kent. 73

[@videossimon4288]

I think the biggest issue is the high swr on the coax between the l match and the antenna. You get huge loss on coax with mismatched impedance. Best having the matcher at the antenna

[@yoki9743]

Thanks Mike for spending the time explaining and going through it with us... excellent video as always... well done that man on reaching the 10k... may your channel continue to thrive and reach the 100k subs that it so rightly deserves... cheers Don..

[@M0JBM]

Well done mike you can now have some sleep ;o)

[@mike-M0MSN]

ZZZ ZZZ lol

[@mikesmithg0rfd356]

thank you

[@mike-M0MSN]

You're welcome

[@ohyeawhosurpoppy]

I like it 👍 ? Make the coil a "roller" with another geared motor you have a three (control) wire ATU for the antenna input point.

[@mike-M0MSN]

Cool idea

[@REKlaus]

I just caught something interesting. At 22:07 the power going to the antenna is indicating slightly higher after the ATU has been tuned than it was with the "perfect match" at the other end of the band. The power out of the radio was the same so could this confirm Walter Maxwell's writings that a conjugate match re-reflects the reflected power back to the antenna and the 2, if in phase, will add together?

[@mike-M0MSN]

Yes well spotted. :)

[@justmejonboy]

So if I understand correctly, when the transmitter and aerial are matched (in maybe an ideal world) the total impedance is purely resistive, there is no reactance. Xl = Xc = 0. 50 ohm at the TX and 50 ohm at the aerial. As mismatches are introduced due to the aerial being either to long or to short the impedance is no longer purely resistive, its now inductive or capacitive. The ATU adjusts this mismatch from the view of the transmitter even though the impedance at the aerial hasn't changed in reality ?? Presumably as inductors and capacitors also have losses it won't be a perfect solution. I found this so interesting to see. Thank you. Watching this has also given me an appreciation of why when using an end fed aerial why a matching transformer is used. When an aerial end fed the impedance seen by the transmitter is much higher, by using the matching transformer it is the same as using a machining transformer to match an audio amplifier to an 8 ohm speaker. Never think these tutorials send people to sleep. This is fuel to my brain, thank you so much !

[@mike-M0MSN]

Brilliant

[@videossimon4288]

Your bananas 😝

[@mike-M0MSN]

🍌🍌🍌🍌🍌🍌🍌

[@M7BXR]

Hi Mike, lost in me this one! How about a small Direction finding antenna? Keep up the good work.

[@mike-M0MSN]

Noted

[@kellypaws]

Think I might have tinned them before putting them on the former. Might make it a little easier.

[@madalinbetea9871]

Hello Mike i want to build a OCF full size dipole . I have a 2xFT 140-43 toroid for 2 core 4:1 guanella balun but i don't know winding number ???.

[@mike-M0MSN]

www.dj0ip.de/balun-stuff/1-vs-2-core-baluns/

[@neilhankey2514]

Nice video but I can't understand why everyone is picking on the ATU? It purpose is to match the antenna to the rig, allowing people to successfully use none-resonant antennas for whatever reason that may be. Small gardens or multiband operation etc… The problem is that you’re experimenting without understanding any of the maths. Impedance Z = is a COMPLEX number that describes the phasing of the voltage and current. So the ATU is phasing the energy in a way that the antenna can except without causing reflections, essentially more of the power is radiated the first time around which is what we all want. Finally, the additional energy is coming from the capacitance and inductance use to match the antenna. Power is another COMPLEX number and you really need a power meter that can measure the phase angle. Finally, every piece of wire whether it is an antenna or not can be reduced to its L C R components where R is purely resistive. Whether you use an ATU or not “Copper Losses” I2R cannot be avoided, they can only be reduced.

[@mike-M0MSN]

Fantastic, information many thanks for your post. 👍👍👍

[@tomstrum6259]

"At 22:07 the wattmeter is" ...I Don't see any power meter at vid frame 22:07, it's the End ! ....What Frame # youall referring to please ??

[@mike-M0MSN]

Long time ago now sorry, I may revisit this subject and make a new video with a better clearer explanation..

[@dandypoint]

I don’t understand you thinking some power goes to ground. I also was not clear on where all the meters wet in the circuit. I do like L networks and have built and used them for many many years on end fed wire antennas. They are fool proof. Only one setting of the coil and capacitor gives minimum SWR where T networks can easily be mis tuned. It looked like you used your L network at first and then switched to the commercial tuner with one inductor and two capacitors. You were right on the reflected power bouncing back and forth between the antenna and the tuner. The coax has some loss so there is an initial loss in dB on the first trip. The first reflection will have the same dB loss on the way back. Then all the power left is reflected back to the antenna and again there is the same dB loss. Eventually all the initial power is either radiated or burned up in heat! The initial power loss is what would be lost under matched conditions. ( what is in the manufactures catalog). All the other losses are due to the SWR. There are charts in the ARRL antenna book that you can use to see how much you will lose for any SWR vs the matched loss of the coax.

[@adelarsen9776]

A quiet voice is heard further away.

[@mike-M0MSN]

Indeed

[@videossimon4288]

Power meters will not be Accurate in a mismatch because it’s measuring the reflection as well as the output

[@Joe-KN4IFI]

Nice detective work Mike. Well done. Gratz on the 10k subs. Question: Since you have had the FTdx10 for awhile how do you like it so far? 73 Joe 🍌🍌🍌🍌

[@mike-M0MSN]

Thanks for the post, the FTdx10 is brilliant by far the best radio purchase I have made since the TS-890

[@americaswayout4489]

Nice experiment and info!!! You didn't say much about how the motor works or where it came from? Years ago Crush Craft built an antenna system called the R3 which had a control box, a capacitor at the base of the vertical and was motorized. I have the control box and a capacitor but no motor. Many antennas could be tuned with it and later the R5 and R7 were used. I need to find a motor. The little box for inside gave a positional feedback with a view of the position, so a vertical near 20 meters resonance could likely be tuned upward. Just another unfinished project !!Like this one- kzbin.info/www/bejne/mZzWl3uharF7Z9k

[@mike-M0MSN]

The motor is a eBay purchase for use with the capacitor again for use with a Loop antenna I am building ( video to come soon). cheers.