Hi mate, thanks for the tutorial. There is a lot of great information here! Iv been trying to do a bit of research on yagi antennas and have a few questions im hoping you (or anyone in the comments) can answer for me. 1) When you are making your driven element, (the steeman yagi antenna calculator seems pretty good for calculating element lengths from what i can tell) it appears you remove 1/4 inch material from the middle to create the 1/4 inch gap between the two halves of the dipole. is this correct? wouldn't it be better the cut the the driven element directly in the half and just space the 2 halves 1/4 inch a part? 2) Some designs like the design show at the bottom of the steeman yagi antenna calculator page use a gamma matching rod. when you compare something like that to a more simple design like you have shown in your video, is there really much of a difference in terms of performance? 3) This is the only design iv seen so far that connects the reflector element to ground. why do you do this and how necessary is it? 4) I've seen some designs use a "hairpin match" which eclectically connects the the two halves of the dipole. what is the purpose of this and why do you choose not to use one? 5) I've seen some designs that don't insulate the parasitic elements from the aluminum boom. does it really matter? apologies if you clearly explain any of these points and iv just missed it. my little pea brain is slightly overwhelmed! any help/advice you (or anyone) can give is highly appreciated!
It’s probably just a more solid way to attach the elements to the mast. I’d do it a similar way with 3D printed parts too TBH but that’s cause I do SOTA so would want it as portable as can be.
You can just chuck that copper tube in your drill. Then get a piece of wood with a hole that is slightly bigger then the tube. Put the tube through the hole. Spin the tube with the drill dragging the wood at an angle down the tube (starting from the drill).
Hello, just wondering about your circular holes. Since they go all the way through, why didn't you simply cut out the profiles instead of pocketing ALL of the material away? Profile cuts would save a LOT of time AND wear on the cutter. Didn't watch the whole video, so if I missed something important, sorry.
Im new to ham and ive just built a 70 cm 7 element yagi it has TIG rod elements and a non conductive boom i did not connect the reflector can you please explane the why its needed and can i just run a wire down then boom to connect them thank you for your time and help
Thank you for your video on your spindle. I thought you were quite informative. I have a Shapeoko xxl and thinking of getting a Rattmmotor spindle kit from Amazon Canada, the exchage rates from US is brutal and don't want to spend a fortune. Your video is about 3 years old at this point in time. Have you had a good experience since installing yours, is it worth while. I use mostly hardwoods and have replaced my dewalt routers 4x in 3 years. I would appreciate any feedback. Thanks again😊 Andrew
Hi, I am building one or the 144MHz, do you guys have any suggestion about the thickness of the pipe? I heard that the pipe diameter will decide the bandwidth of the antenna.
For whoever is interested - a little different test circuit. I have a 2002 CR-V. The original simple test using only a 12V source did not work. Wired a little differently it did: P1 on ground, P2 on 11V. Result: 9.8V on P3 (1.2V lower than 11V) Connected like that, tapping P3 to ground makes the valve jump a little. This made me realize that this IACV valve does not just consist out of two coils but that there is some electronics in it that probably amplifies signals coming in on P3. There is no need to include a mosfet in the circuit. Just connect pin10 of the Arduino to P3 of the valve while connecting the ground of the Arduino with the ground of the power supply. I configured the sketch's IACVBaseFrequencyHZ to run at 500 Hz. Warning: It's probably best to make sure your grounds are reliable. Otherwise you might let the smoke out of something. Don't power the Arduino from a laptop connected to the wall while you power the valve using a power supply that is connected to the wall too. Either run the arduino from it's own isolated 5V power bank or use a 12V battery to power the valve. That way it's safe to connect both the 5V ground and the 12V ground together. The valve draws about 170mA max at 11V to move smoothly while the current between Arduino pin10 and P3 is about 3mA.
This pinout explanation doesn't make sense. Why are both pins 1 and 3 control pins? And you can just attach a 12V signal to the device without completing the circuit with a ground? When i looked at Acura service manual, it states that pin 2 is 12V and pin 1 (on connector to iac valve) is ground. The "default" state is the valve is in "closed" position -- which still allows some minimal air flow in this position. In default position, pin 3 is not activated by ecm and is 12v, When ecm activates pin 3, it pulls that pin to ground, opening the valve to its widest (and only) 'opened' position. The duty cycle of pin 3 determines air flow.
The IACV of my 2002 Honda CRV seems to follow your logic. I connected P1 to ground and P2 to 11V. P3 then reads 9.8V (1.2V lower). When I then tap P3 to ground the valve moves a little for a moment. I'm about to build the suggested little Arduino tester to see the full range of movement of the valve.
@@cobbles62 if you have scan tool with bidirectional control, you should be able to adjust the iac valve through the scan tool. I'm going to do that this weekend.
@@yusuihang I would love to have one but the cheapest one I could find is $300+ Besides, if the valve does not work using the scan tool it could also be a wiring or an ecu issue.
Those terms are used in a nice, free Yagi Calculator. That person calls the driven element the dipole. Somehow even though the guy that designed and uploaded the Yagi Calculator used the "incorrect" terms, thousands of folks have made really nice yagis with it. And there's another really important piece of information here. The guy/gal that made this nice calculator may be using English as a second, third, or fourth language if not more. I don't know about you but I only speak one language. Have you ever written instructions? Give them to five people and you'll receive five sets of things you did "wrong" with said instructions. So my hat is off to the person that gave us the chang something calculator. I for one used it to sniff out Power Company Equipment that was ruining my radio hobby. In one hour I found the bad component/s. Even though the calculator maker called the driven element a "dipole". Which.....it actually is. Oh well. Some folks should just buy what they need. And to oh so illustrious maker of the Chang something calulator, thank you. And always remember. "No Good Deed Goes Unpunished!"
I've made a 5 element 1.6GHz Yagi with a signal element that's 90mm long. Using 2mm bare wire as elements. I have to cut this piece into 2x45mm pieces to hook up to the coax cable? What about the 2-3 mm minimum distance I can manage keeping them apart? Does the gap between the ground and signal poles matter? Do I have to trim the length of the wires after assembly?
what size rims and tires are you running, also did you do any mode to get those rim/tires on your x-sport? I have an 03 x-sport and want to get bigger tires and the snorkel on it too. I live in the SW and we have lots of dust and very lil streams, so for me it will be for cleaner dust free air.
try your local library, if you're in the US. Mine won't allow me to print other people's designs, but the town over allows me to print for 5 cents per gram of plastic.
Why Inches? Needs To Be Inches AND Metric Systtem Please, But Damn, I Need 3D Printer, Sadly Im Poor As Dirt :( Butt What A Cool Yagi Antenna Man, Love Your Enthusiasm About It, Same As Myself. Love To Make Everything Myself
Antennas are measured primarily in SWR, which is signal quality. The range is limited by earth's curvature but you can actually reach the space station (250 miles) with a properly built yagi. With ham radio or GMRS you can reach repeater stations which give you great quality and distance of about 20 miles. There are some issues with this antenna design but the 3d printed parts are beautiful. I will use the 3d parts, but will design the elements and their measurements off of "$4 space station yagi". If you're using GMRS you will want to calculate frequency at 465Mhz
Got a P0505 and put a brand new one on, still surged idle. Pulled it back off and gave it power and ground and the new part was defective from the box.
local library, if you're in the US. Mine won't allow me to print other people's designs, but the town over allows me to print for 5 cents per gram of plastic.
Its a rack I welded myself goes front window all the to the back and overhangs the track width my 2" its huge and in the future I will be building them in a more reasonable scale.
My IACV is a plunger style. there's a visible shaft inside with its return spring clearly visible. I plan on doing your electrical test but wonder in the meantime if the plunger is frozen in the IACV because I cannot move the shaft at all with a screwdriver in any direction. Seems locked in a closed position. Great video, tx! Also, I've cleaned the IACV 3 times with carb cleaner. Idle description: once the truck is fully warmed up in gear, the rpm's at are at 400 and in neutral the rpm's rise to 700-800.
Is the IAC controlled only when in park/neutral or is it also controlled when it is in gear? Reason I ask is because I have a rough idle that surges when in park/neutral. Once I put it in gear it smoothes right out. I am stumped.
Hi, I notice you didn't pre-heat the head or acid dip it - in your opinion are those steps really required and have you had any problems welding aluminium without pre-heat? Cheers.
I think the reason cylinder 5 has corrosion on the right, but cylinder 1 and 2 have it on the left is because the corrosion is close to the intake valve. On the Eurovan, the pattern is Ex In Ex In In Ex In Ex In Ex. I don't know why the trouble spots are near the intake valve and not the exhaust valve. I wish for the best repair no matter the situation. The Eurovan was uncommon in the USA, most were sold a Westfalia or Winnebago RVs. They are treasured, so an expensive repair is worth it.
Thanks....but I checked out at "3D-printed brackets". Cute, but I'd rather do something with off-the-shelf components. Maybe I'll check it out later.....
Could you answer a question I have about antenna. Would using elements that are larger in diameter than standard needed and having schotsky triangles cut into the metal around the circumference increase the gain and signal to noise ratio ???
Nice video for a beginner, some new ideas printing the antenna supports, and it is very obvious some thought went into building this antenna instead of "buying off the shelf" that so many do, but do not learn the principles of how it actually works. Nice job! Next time you will do much better! 73's de W4FJF.
I would suggest two reflectors, and five directors (always an odd number for directors) for greater forward gain and a greater null towards the back of the beam. Add a non conductive holder at the back of the boom to avoid RF burns (even at five watts you can get an rf burn holding the boom). Depending on the coax you use, this beam can be used up to 25 watts power into the antenna. I recommend RG-8X for all power levels because there is little loss from the coax and RG-8X is flexible enough to bend at a 2" radius.
There's a reason that no one uses two reflectors. Zero benefit is the main one. And you "recommend" 8X? In a three foot run? Seriously? Have you ever built a successful antenna or do you just THEORIZE about stuff?
Wouldn't it be easier to have all your small parts in a bowl? That way you do not have to search for those parts all over the Table. Soldering to copper pipe can be done by tinning both wire and copper tubing before hand so your supports will not risk being melted.
Your "driven" element (or dipole) MUST NOT touch the boom in any way. It must be free floating above ground potential in order to work correctly. The directors can either be free floating or connected to the boom depending on your design. This again is where Oxyguard comes into use on the directors because it protects the copper directors from the aluminum, yet supplies electrical contact if you wish, or your mounts can be free floating also in your design. At the center of each element, the RF current will be zero - so it almost doesn't matter.
