Be NEAT in your construction !!! Neatness adds efficiency in the circuit. Maybe not so much, but enough to make a difference. Also, increase the wire diameter on the inductor, it increases circuit "Q" where you need it. Use #16 AWG in all wire connections, otherwise you risk circuit loss. Otherwise, fairly well done.
@TheArtofEngineering
6 ай бұрын
Thanks for the feedback. Yes it could be neater, the process is always a battle between the impulsive excitement of creativity and the stringent demands of RF design. I did have to go back later with a higher wattage soldering iron and resolder parts. Thanks for the tips and for watching the video 73 OM de VK2AOE.
@billwilliams5965
6 ай бұрын
Hmmm... Me being old (70), I like old school !!!!! Cheers
@TheArtofEngineering
6 ай бұрын
Old? 70 is the new 40😂😂 73 de VK2AOE
@twkiller
9 ай бұрын
I think L-match very easy and funny. Where can get more information about it?
@TheArtofEngineering
9 ай бұрын
Check out the links in the video description! Some good stuff there. Tnx fer the comment 73 de VK2AOE.
@cthoadmin7458
8 ай бұрын
A better name for your channel would be "Radio at the Edge of Sanity"! 😀
@TheArtofEngineering
8 ай бұрын
YES!!! This hobby is literally a return to childhood. Radio is magic…. Magic waves…. Magic smoke….. magic TOYS! 73 de VK2AOE 😝
@cthoadmin7458
8 ай бұрын
@@TheArtofEngineering It's as Nietzsche said "Inside every real man there's a child, and he wants to play!" de VK4QP
@TheArtofEngineering
8 ай бұрын
@@cthoadmin7458 YES! Jung expressed a similar idea....If life lacks inspiration...play like a child! 73 de VK2AOE
@twkiller
9 ай бұрын
What difference the crocodile clip line at xmit/rcv and ant?
@TheArtofEngineering
9 ай бұрын
Not sure I understand the question? If you mean what does the clip do.....it basically allows you to vary the amount of inductance. This video might help kzitem.info/news/bejne/po56n6Z3iH-Qomksi=u9ULpWNNbgELZqpL
@utubercj
Жыл бұрын
Cool site :
@TheArtofEngineering
Жыл бұрын
Thanks …. More in the making 73 de VK2AOE
@hamradiofun5527
Жыл бұрын
What is the value of each hand on the variable capacity? What is the total value of the inductor?
@TheArtofEngineering
Жыл бұрын
Mine was from an old AM tube radio. Because the plates are spaced close it is only good for lower power output…. Cap value not critical but approximately 540 pF per gang? The L ?…. 20 to 30 turns on the pvc former. Like I said in video this is based on another hams project ( That Old Tech Guy -Kevin Loughin)… kzitem.info/news/bejne/po56n6Z3iH-Qomk
@twkiller
9 ай бұрын
Thanks om I have another question. How to calculate the inductor coil number of turns?
@TheArtofEngineering
9 ай бұрын
I use an LC meter…. But the bigger the coil the bigger the “mismatch” the L match can cope with. … keeping in mind a big mismatch for a coax fed antenna means a less efficient antenna. I usually work with antennas that are as resonant as possible to start with using my nano VNA. So the L value is not “critical” …. Just make a big one with lots of taps. 73 de VK2AOE
@twkiller
9 ай бұрын
How about the SWR in 14Mhz?
@TheArtofEngineering
9 ай бұрын
I think it depends on the antenna it is plugged into, and the extent of the mismatch…I use mostly resonant antennas 73 de VK2AOE
@Adam-qd8jh
Жыл бұрын
What are the lengths of wire that should be used with this tuner? Could I use a 1/2 wave ?
@TheArtofEngineering
9 ай бұрын
If the antenna is too short you need to add inductance and if it is too long for the frequency of interest we add capacitance. I would say starting with a half wavelength at the lowest frequency you require will get you close enough to then tweak it with the L - match. You could also look up “random length wire antenna”…. and try that… I haven’t done that and would be interested to see how that goes? 73 de VK2AOE
@inkits1
2 жыл бұрын
I am building hf antenna 2.5mt vertical with lc match tuner... Do we need a conterpoise?
@M7XOM
2 ай бұрын
Your NanoVNA is not calibrated. The c mid left side of screen should be C. Uppercase means it’s calibrated, lowercase not.
@TheArtofEngineering
2 ай бұрын
Thank you....I normally calibrate whenever I change the range of "stimulus". I must of not done it in this case. Thanks for that tid bit of useful information that I didn't know! Just tried it and 100% correct. Nice to know as it will remind me to do it! 73 and TU OM most useful.
@frankartieta4887
11 ай бұрын
What makes this QRP ? This can be higher power than qrp This is nothing new I do not even say this is old school This is as practical today as ever I can not speak for the ugly building though
@TheArtofEngineering
11 ай бұрын
The spacing of the plates in the capacitor means running high power risks it arcing. That is why I wouldn’t risk my finals on it. 73 de VK2AOE
@frankartieta4887
11 ай бұрын
I can tell you off hand the spacing of the plates in a air variable capacitor such as yours. Would handle well beyond 5 watts. I use Polyvaricon Variable Capacitors in most of my qrp gear and they handle QRP power levels with ease! I do not blame you though :) Better safe than the dreaded smoke ! es 72 de kd5ald@@TheArtofEngineering
@TheArtofEngineering
11 ай бұрын
@@frankartieta4887 Yes ....rather than say "lowish" power I was being extra cautious. I have seen a few tuners using those caps you mentioned and they seem to work well! My mooncake xmitter uses one to tweak the ceramic resonator for some frequency agility. TU for the comment 73 de VK2AOE.
@inkits1
2 жыл бұрын
BTW my call sign is vu3sua. Best of 73s
@TheArtofEngineering
2 жыл бұрын
I am currently using this unit with an end fed 1/4 wave 7 Mhz antenna...with a trap and "small tails" at the end to get a small resonant dip on 80m. It seems to work with or without the counterpoise attached to the UNUN (49:1). I guess it depends on the antenna? The thing also to remember is just because things are a good match, doesn't mean the antenna is effective (a 50 ohm resistive dummy load is a perfect match but you can't work DX on it!). As long as the VSWR is acceptable .....you could experiment and see how well it "gets out"? Video link to a series of videos on my current antenna .....which soon will be higher and better as I now have a 9m pole and will make it inverted V 1/2 wave for 80m! kzitem.info/news/bejne/ppCrs5efiWqgmZw de VK2AOE 73
@inkits1
2 жыл бұрын
@@TheArtofEngineering thanks i appreciate your advice. If I am using an LC Tuner with the whip I presume I do not require a matching UNUN ?
@TheArtofEngineering
2 жыл бұрын
@@inkits1 No the UNUN is because the 1/2 wave is end fed where the impedance is high. whips have low feedpoint impedances approx that of the coax (50 ohms)....most often! Does your whip have specifications?
@TheArtofEngineering
2 жыл бұрын
@@inkits1 2.5 m vertical ? What frequency is it for? 28 Mhz 10 m band?
@inkits1
2 жыл бұрын
@@TheArtofEngineering i am going to make this antenna for hf handy . Operating on 7mhz to 28 mhz So should I use a matching balun or an LC Tuner will be good enough . The antenna is being manufactured locally for 2.5mt . It's not being made by any company but I have ordered to be made from a company that makes RF products.
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