Absolutely fantastic splitter/combiner explanation I've seen. I don't know what your profession is, but you know the subject you are explaining. Pure enjoyment!
Thanks for taking the time to make videos. I find them to be interesting, informative and easy to learn from. Understanding RF design has always eluded me. I think because most engineers are not good teachers. They tend to teach way above most people's level of understanding.
Love your videos mate ... you're giving me so much to think about, and you've introduced me to a number of rabbit holes that I feel obligated to explore! 73 ... VK4KYT
your the best sharky im always super stoked when i see a new sharky joint. thank yo again for all the contributions to the hobby on behalf of the comunity we thank you greatly
That great ! I usually use the texas star style splitter/combiner . but on a 8 transistor have to stage it. but with 4 port combiner/splitter do the same all at once. also for odd numbers or pairs like 6 transistors will need 3 port . i do not do this much . tips you gave help me get that coil for tuning right. nice to see you back. my radio hobby is last as well. same type combiners used on AM broadcast transmitters . just big coils and vacuum cap.The outher type of combiner is 2 transmitters on 2 different frequency on same antenna . we use 2 Pi networks tuned to each transmitter.that a bit tricky and hader yet both stations at different power levels. 25Kw and 5 Kw . at AM the coils big as me. this is a case where more DB isolation is needed. same steps you shown just on a bigger scale. you got hands full with kids. I hear them . the fun of life ! 73's
To find the value of the shunt capacitor in the middle of the relay inductance, find the parallel equivalent of half the network (so if you have 50+j11 passthrough, find the parallel equiv of 50+j5.5). Then half the parallel equivalent reactance and that is the reactance of the capacitor you need. So the parallel equiv of 50+j5.5 is 50.605+j460. 460/2=230Ω A 25.4pF cap will have a reactance of 230Ω at 27.2MHz, so that is the cap you need to put in the middle. Thanks for the awesome video, I gotta go finish watching it now. Edit: Re-reading that, I am glad I wrote it that way to make it easier to visualize, but in reality, you can simply take the nanoVNA reading 50+j11, take the parallel equiv of that, and the reactive portion is the cap reactance you need, no need to divide stuff by two.
its great learning this all with you, thanks for explaining all of it so simply for us. I got into this 5-6 years ago and got pretty far but the science behind it has been tough to absorb but youve made it easy
I have been putting off downloading Sim Smith.. heard about it for years but now you gave me that extra motivation to do it lol... one cool thing I love is the whole prog is designed in Java which is really cool. Java is a great prog language to use just like c# when using major math like this one is doing.... Beautiful Video which. Will be used for years and years on. Ps... I have been having a lot of fun with Chat GBT here recently....main thing I've learned though is if you ask if to do to much at once, the information begins to get a little less accurate lol. Chat GBT is gonna change the world man!
Sure glad to see you back on the tube. Hope all is well . I really look forward to getting a couple of your pallets in the future. In the mean time i been working on power supplies. I am currently building a 1000 amp unit. And hope i dont blow myself up . Hope to catch you on 28 or 38lsb. 199 florida georgia line. Take care.
When you connect a small component such as a load, you should hold the body to prevent it from rotating. It will minimize the wear/stress on the center pin and extend the overall lifetime.
Good to see you on again! I live near Pikeville Tennessee. Should try to catch you on the air sometime. Got a Dentron Clipperton L amp that's missing the output Coils. Can't seem to figure out how to make one that resonates at 50 ohms. Maybe you'd be able to?
I'm sure I could figure it out if I messed with it for a while. I generally don't do repair work though, unless it's something so neat I just can't say no.
Your the first PERSON I've heard connected to the 11m community that speaks of the splitting and combining in the way that I teach in my videos :) In the first Explaination, I always call the narrow banded impedance matching network a LC Network since there is an L & C being used but it is in a L configuration. Should I be calling it an L or LC you think sharky? Thanks in advance bud. All of my attempts in contacting you have failed lol but since ur back for now maybe I can have some luck!
Well well where have you been so long I have been missing you glad to see you back on here dude, did you say you moved to someplace in Tennessee hope it's going good keep up the good videos
When are you going to switch to transmission line combiners? Those coils are easy to accidentally de-tune. Also good idea to include vswr protection on each pallet individually to protect against combiner failure. I wonder what is your kit build failure rate? LDMOS amps are touchy things especially using large air inductors for LPF. Would not trust CB crowd building those and not blowing them.
I entered "compute a 50 ohm l-match for an impedance of 25-4j ohms" into ChatGPT and it computed nominal component values. Then I asked it to write a program to do the computation for arbitrary component values which it also did with "write a C program to compute the values". We have moved into new world where we can look at problems with a higher level of abstraction without getting too bogged down in the details. You still kinda need to know what you are doing so that you can spot when the AI feeds you utter (or slightly incorrect) garbage.
I've done a few interesting things like that with gpt. I've seen a lot of bad info too, but it's a great helping hand for the programming languages I don't know very well.
The input of the NanoVNA port 2 is not perfect 50 ohm. I have a permanent 6db attenuator in it that I calibrate with and thus present a better match during measurements.
@@MudDuckSharky Welcome back from Eric @ KY8E and gotta just love the mountains of useful data that Motorola created throughout the years (had the great fortune of being sent to their school in Schaumburg once a year during my 6-year stint as a bench-tech at a Motorola-owned service-center in the 80s).....
Once you figure out in your program, what the capacitance needs to be and that inductance needs to be for the L-network, can you show us how you physically measure the copper induction Coil and the device that you’re using to measure it? Because I’ve tried reading an inductor coil using my LC meter, and the uh don’t change a lot from different lengths of windings very much. So I would like to see the process you use.
