Use ONE COAX to Feed TWO Antennas! Step by Step Easy Build.
Пікірлер: 97
@M7XCB11 ай бұрын
Think you should put Diode across the relay coil? To discharge the current store as magnet field into the coil because you the coil opposite to change in current flow and will act as current source in reverse way when disconnected from the source.
@Steve-GM0HUU11 ай бұрын
Probably a good idea - standard practice with relays.
@edwhitney186211 ай бұрын
Yep, you are right Darren. Thanks for bringing that up. We have to make sure everyone knows : If the positive side of a voltage source is connected to the positive end of the diode (the anode), and the negative side is connected to the negative end of the diode (the cathode), the diode will conduct current. If the diode is reversed, the current is blocked (up to a limit). In our case HOOK UP THE DIODE REVERSED!
@W4YDL2 ай бұрын
Is the purpose of putting a diode across the relay coil to avoid a voltage spike? I noticed that in my setup, when the relay coil is energized/deenergized, there is a huge spike of noise evident on the spectrum scope of my radio. Doesn't seem like a good thing! Lol
@RajaramSrinivasan59 Жыл бұрын
Your systematic and crystal clear steps are so beautifully presented. It's a treat to watch OM Ed! 73 De VU2RJV, handle Raj from India.
@edwhitney1862 Жыл бұрын
Thanks Raj! I try to make them clear. Wow, what a nice comment from India!! -Ed W8EDW
@RogierYou11 ай бұрын
Neat setup. Clean nothing neighbors have to complain about. One idea is that you might have been able to omit the 12v supply and run DC over the coax to energize the relay.
@edwhitney186211 ай бұрын
Hi Rogier. Yep, you are right. Another video project. Thanks so much for the idea! -Ed. W8EDW
@RadioOperator-GMB11 ай бұрын
Hello Ed. Your videos are very educational. All video explanations are great! I look forward to seeing your videos uploaded every day in Japan 🎌 JG3GMB 73
@edwhitney186211 ай бұрын
Hi JG3GMB, Thank you for such a nice compliment. I really enjoy building projects and explaining what I know. I'm certainly no expert but I'm just an OLD ham with years of experience. I hope to hear you on the air! -Ed W8EDW
@bigsky197011 ай бұрын
This video is a great inspiration for me as I was trying to figure out how to make a remote switch work! Thanks and 73 de Stacey, AA7YA
@edwhitney186211 ай бұрын
Your nice comment gives me inspiration to keep making videos! Thanks so much Big Sky!!
@hectorpascal11 ай бұрын
No need to use tape to hold the connector while drilling other holes - just nut and bolt the first hole using a lock washer, line it up and tighten it well, then drill the rest!
@edwhitney186211 ай бұрын
Good point. If you notice on the video I did both. LOL! Just extra being anal that it doesn’t move. Thanks for the comment Hector! -Ed. W8EDW
@TheREALJosephTurner6 ай бұрын
Just subscribed. Love your presentation style, and LOVE that you show part numbers in the video. Thanks!
@edwhitney18626 ай бұрын
Thanks Joseph. Really appreciate the nice comment! And thanks for subscribing! -Ed W8EDW
@channelview885411 ай бұрын
Love the video. I like the way you get things done. The important thing is results and you can make things happen.
@edwhitney186211 ай бұрын
Hi Channelview. I really appreciate your kind words! That gives me inspiration to keep trying to make fun informative videos. -Ed. W8EDW
@N1IA-410 ай бұрын
Such a great video, Ed. So, so well done. Probably the best instructional ham video that I've ever watched on KZfaq. I am in process of building a different type of remote antenna switch...one that uses a NOS Amphenol coaxial relay from EBay (26.5 VDC) , a 26.5 VDC power supply from Amazon, and a G-Home Smart Mini Plug (120VAC from Amazon) connectable to wifi and the internet so that I can switch two of my antennas remotely in my 2nd QTH a few miles from my physical station. Gathering the parts now. I can switch 3 antennas using the rig interface and a VPN and operate great (I even have Two WinKeys for remote CW) but because I have a 4th antenna I need to build something to accommodate it. I want to put the PS and relay in an aluminum or metal enclosure with 3 SO 239s like you did. Then an AC cord coming out to plug into the Smart Mini Plug. You did such a great job on this! I kind of wondered why you were using such a heavy-duty enclosure but then saw why..it's in a garage or shed! hihi.In my case, it will be in my shack so I can use aluminum. Thanks again for doing this. I wish more hams would venture into homebrew stuff. 73 de Scott, W1AL
@edwhitney186210 ай бұрын
Hi Scott. Thanks for the wonderful comment! Sounds like you like to have fun building your own equipment too. All I can say is wow! You really have some cool ideas for your antenna set up. You will have to email me with your build’s. I’m good on QRZ. I would be happy to feature you on my channel. Thanks so much Scott! -Ed. W8EDW
@N1IA-410 ай бұрын
@@edwhitney1862 I'm making the video now which goes over the entire project. It will be on my KZfaq channel at www.youtube.com/@soakland5. Yes, it would be an honor to be featured on your channel.
@kennethausten11 ай бұрын
Done this via a UHF link remote. Antenna relays all burnt out in time in my case running about 50 watts . Contacts went HR. Similar relay. I soldered a flyback diode across the coil circuit. This suppresses the high voltage Back EMF which could damage your PSU or other electronics if connected. This was standard practice in the profession I was in. Worked well for a few months, but the relays were obviously inadequate. I need proper coaxial relays. At £40 each it's not viable when I need 4 of them. Now converted to a patch panel.
@edwhitney186211 ай бұрын
Hi Ken. You should do a video about your experience! Love to see it! Thanks for watching mine! Cheers! -Ed
@Doonit_hard_way_since_659 ай бұрын
W6PQL has some info on using small commercial relays for switching in his 2KW amp. If you are damaging contacts you are either hot-switching them, have a high SWR missmatch or have enough voltage drop in the control line to leave a lose contact. Reglar old Omron gr2 series easily handle 1.5kw on digital modes with 100% duty cycle on 160-6
@richardhole842911 ай бұрын
Looks good. I would check the coil current to make sure the wire back to the shack is allowing full rated current. It not you can boost the voltage until the coil current is sufficient. 73 de N8RL
@edwhitney186211 ай бұрын
Good point Richard. I used 14 gauge wire and my power supply will go up to 18v. Thanks for the suggestion! -Ed
@rickhole11 ай бұрын
@@edwhitney1862 If the relay coil doesn{t get enough current the contact could in time wear or overheat. Using both contacts in parallel is a good idea. And I wouldn't worry much about the diode with nothing else connected to the supply.
@zaperfan Жыл бұрын
Great project very well explained thank you
@edwhitney1862 Жыл бұрын
Thanks for the nice comment Zaper! Very Electric! LOL! -Ed W8EDW
@7X2TT5 ай бұрын
Brilliant project thanks for sharing. 73 de 7X2TT
@edwhitney18625 ай бұрын
Thanks Mesbah. I really appreciate the nice comment! Hope to work you sometime. -Ed W8EDW
@M7BVV-Phil11 ай бұрын
Thanks for this informative video Ed, you have just solved my problem best 73 from U.K.
@edwhitney186211 ай бұрын
Glad it helped
@AB1Vampire11 ай бұрын
I did something similar but used a latching relay so no need to keep relay energized. Nice video. One question I had was whether is matters if a metal or plastic box is used. 73's n2eye
@James_Bowie11 ай бұрын
latching relay for the win.
@James_Bowie11 ай бұрын
latching relay for the win.
@edwhitney186211 ай бұрын
I really like the latching idea! Yes, I would definitely use a metal box for shielding. Thanks so much for your comment! -Ed W8EDW
@AB1Vampire3 ай бұрын
Surplus Sales of Nebraska is where I got mine and it was not a lot. I used a DPDT Momentary switch wired to change the polarity to switch it back and forth with only a 2-wire connection. (KO) 110636 AB Industries dual DPDT relays operated with common armature that mechanically toggles to each resting position. Can use either both coils or one coil with reversing polarity. 10 amp contacts. 12v DC coil. Use anywhere maintenance of circuit integrity during a power loss is important. Maximum dimension 3.25" x 1.75" x 1.375"H.
@user-on3fu6yl3v7 ай бұрын
Hi Ed. Firstly, let me say I appreciate your intention and spirit... a true HAM. I have a few suggestions, and a few critiques. So, right to it: On your praise of these Baomain relays, I bought 2 from Amazon.... they are CRAP! One look tells all... the contacts are VERY POORLY aligned and the contact patch is miniscule. the brackets that hold the upper (NC) pads and the lower (NO)contact pads are leaning every-which-way, so those contacts are not on the same plane as the armature pads. The plastic part of the Armature is so poorly designed that the arms that hold the common pads are not held in alignment, so are as much as 1/8" off center. This results in terrible contact fidelity and therefore sketchy (at best) opportunity for proper low resistance connection.. I am returning them and searching for a quality relay that I can afford. :-) But on to the design suggestions. With a good DPDT relay that offers good connection, I see no reason to use both contacts in parallel for the connection of signal. I suggest, in keeping with design practice common to physical antenna switches, why not use one contact for signal and the other to ground the unused antenna to provide some isolation. So, in a non-powered state, the first set of NC contacts connects signal to your default antenna while the second set of NC contacts connects the unused antenna to GND. When the relay is powered, the first set of NO contacts (now closed) connects the default antenna to GND and the second set of NO contacts connects the signal to your second antenna. 73
@edwhitney18627 ай бұрын
I have been using the relay switch for quite a few months with no problems. BUT you are right, you get what you pay for! Maybe make a video on your build. I look forward to it. -73
@stevendevonside464711 ай бұрын
Brilliant Video and very neat work.
@edwhitney186211 ай бұрын
Thank you! Cheers!
@lmachielse70775 ай бұрын
Ed, thanks fot this nice video, 2 questions how to connect the + and - on the 12 volt with connectors other question can you make a video how it work with 2 antennes ? thanks again
@edwhitney18624 ай бұрын
Hi Imachielse. The + and - doesn't matter. The coil on the relay will work either way. I will be making a video using the antenna switch when a little warmer weather hits. Probably in May. Thanks so much for watching! -Ed W8EDW
@microflite6 ай бұрын
Nice project but won’t there be a big impedance mismatch at the switch? That’s the reason manual antenna switches are built in a specific way and don’t have long wires.
@edwhitney18626 ай бұрын
Hi Micro. I haven’t noticed any high SWR problems. I’ve been using it for quite a while now. I’ve been running low power and up to 500 watts with great signal reports. -Ed W8EDW
@ryanjones93058 ай бұрын
Great video. I actually have two of those relays just sitting around. I don’t have the fancy box that goes around them though. Be curious as to how well that would work with 2 and 6m. That’s my current antennas switching problem to solve. FB OM. 73, NV5E.
@edwhitney18627 ай бұрын
Thanks Ryan. Honestly, you might be better off with a “commercial “ version for the higher frequencies. The lower frequencies are more forgiving. Good luck! -Ed. W8EDW
@colint11 ай бұрын
The contact gap on that relay looks pretty small, I'd be worried about arcing. Also is the relay rated for RF/AC or just for DC, you might have a problem with not enough "contact wetting" despite the large contact area. At HF the impedance match probably doesn't matter but at VHF and above a coaxial relay would be better.
@edwhitney186211 ай бұрын
I am only using the switch on HF. It seems good so far!
@hectorpascal11 ай бұрын
@@edwhitney1862 it really just depends how lucky you are. If the power is high enough, the antenna impedance is less than ideal, and the cable length and frequency are "unlucky", a standing wave voltage peak might just coincide with the position of the contacts!
@Doonit_hard_way_since_659 ай бұрын
Lol, those contacts are huge, and so is the gap. The little omron G2RL series works completely fine up to 1500w on 2 meter with any sort of acceptable SWR. Most likely why they are the most common switches found in amps hf-2m. Only real worry with his relays in stray reactance from the long contactor leads.
@edwhitney18629 ай бұрын
Hi Colin. Sorry about the late response. I’ve been running that relay over a year now with good results. So far so good! Thanks for the comment Colin! -Ed W8EDW
@danielmckay71856 ай бұрын
Thank you for this great video. This would really help me out. My antennas are a good 75’ from the shack, doing this will save on buying long lengths of coax. I was curious about how much power you are running through it. Also, how do you think it would work on UHF? Again, great idea!
@danielmckay71856 ай бұрын
I was reading the other comments and found that you are running about 500 watts. How is it holding up?
@danielmckay71856 ай бұрын
73’ K2AED
@edwhitney18625 ай бұрын
Hi Daniel. I run around 500 watts. I don’t think you would have any problem with legal limit on 10 meters and down. I’ve never tried it on UHF so let me know if you try it! Thanks for the nice comment Daniel! -Ed W8EDW
@edwhitney18625 ай бұрын
No problems after 6 months. 👍
@danielmckay71855 ай бұрын
@@edwhitney1862 Thanks!
@n5yiz Жыл бұрын
Very nice Ed!
@edwhitney1862 Жыл бұрын
Hi Preston. Glad you liked it! Maybe use something like this switch to easily use two different antennas on your Mobile. See you on the air! -Ed W8EDW
@leakyboatent-fr1yw11 ай бұрын
A latching relay would have made the switching voltage momentary. Well made though, thank you.
@edwhitney186211 ай бұрын
Hi Leaky. Yep, you are right. I was trying to keep the build cost down and couldn’t seem to find an inexpensive latching style. Thanks for the nice comment though! -Ed. W8EDW
@woodsjl10 ай бұрын
Awesome video ED !! Thanks for sharing. May try this project this fall. 73 de KD4FZY
@edwhitney186210 ай бұрын
Thanks Jerry! It was a fun project and works well. See you on the air! -Ed. W8EDW
@rodw7zrc22 Жыл бұрын
Very clear, nicely done video Ed. 73, Rod/w7zrc
@edwhitney1862 Жыл бұрын
Thanks Rod! I hope we work on the air sometime. I appreciate the nice comment! -Ed W8EDW
@mikeiver11 ай бұрын
OK idea though not exactly impedance matched. Also used the wrong box, should have used a NEMA 3R box or even better a stainless steel NEMA 4X box. The contactor used is for power rather than RF but if the wires are kept extremely short I would guess it should work OK.
@edwhitney186211 ай бұрын
Thanks for the information Mike. It seems to work fine so far (about 2 months) almost every day
@edwhitney186211 ай бұрын
By the way Mike, thanks for taking the time to give us good information! -Ed. W8EDW
@bradleyjohnson45211 ай бұрын
Well presented coax switch project. Might be a good winter project. What are your thoughts on building one that when the power is disconnected it grounds to earth to discharge static buildup during lightning?
@edwhitney186211 ай бұрын
Hi Bradley. Great idea! Let’s design a circuit to do that. It will be fun to find parts and buid it. If anyone has a design that uses common parts send it to my email. (Good on QRZ) -Ed. W8EDW
@user-on3fu6yl3v7 ай бұрын
@@edwhitney1862 what is your email Ed?
@W4YDL2 ай бұрын
I just built something exactly like that today. I have the antenna positive and negative connected to the common of the relay. Normally closed contacts are both grounded to my ground, which leads outside to a 8ft ground rod. Normally open contacts are connected to the SO239 that my radio connects to. Power to the relay coil is provided by my power supply, which is connected to a smart outlet. My reason for doing it this way is to remotely disconnect my radio when I am operating remotely. I use the smart outlet to turn on my power supply via the Alexa app, which energizes the relay coil. Once the coil is energized, my antenna switches from ground to my radio. I also have a grounded lightning arrestor outside in line with my coax, but this is providing a little more isolation (not much) for my radio.
@jamess1787 Жыл бұрын
73, thanks Ed. 🙏
@edwhitney1862 Жыл бұрын
Thank you so much James! -Ed W8EDW
@cWatts-zv3oo10 ай бұрын
Hi Ed. Presuming you have the other antenna built by now, are you experiencing any tuning problems with the additional shield added from the other antenna? Thanks.
@edwhitney18629 ай бұрын
Hi cWatts. Thanks for asking. I temporarily used my screwdriver antenna hooked to that side of the relay and didn't have any problems. It's definitely on the spring agenda for a permanent 10m antenna! -Ed W8EDW
@bgorveatt11 ай бұрын
How much power can this take? 100 watts obviously but beyond that???
@edwhitney186211 ай бұрын
Hi bgory, I run 400 to 500 watts through it. I am pretty long winded. And I've checked for heat on the relay. So far so good! -Ed W8EDW
@mktwatcher11 ай бұрын
Why not use a solid state relay?
@edwhitney186211 ай бұрын
Hi Mkt. Good suggestion. Which solid state relay with enough power handling do you think will work? Thanks for watching! -Ed. W8EDW
@XPFTP11 ай бұрын
you feed 4 tp 600 thru it ?? held so far it seems
@edwhitney186211 ай бұрын
Hi XPFTR, Yep, I run about 400 to 500 watts through it with no problems. I think that the large contacts and putting them in parallel works. I'm pretty long winded on the air too! Thanks so much for your comment! -Ed W8EDW
@n1kkri11 ай бұрын
would you mind listing the Amazon items? Thanks
@n1kkri11 ай бұрын
Did you scrape away some of the box coating where the ground screws and straps go?
@edwhitney186211 ай бұрын
Hi N1KKI , Yes I did scrap the paint off. But I wanted to be doubly sure that they were grounded together. Thus, the straps. Good point, I should have mentioned it. Thanks!
@edwhitney186211 ай бұрын
Sure be glad to. My email is good on QRZ. Send me your email and I'll give you the numbers. -Ed
@j.cabarga597111 ай бұрын
"Just applying the SOLDER to the tip of the iron" is exactly the WRONG way to do it! Amazing how many 'experts' on utoob don't have any idea how to solder, yet they claim to teach others how to do technical things - also, "just 2 screws needed" to attach the terminals to the box is ALSO the wrong way to do it! Sorry, but being LAZY does not equal being good at what you do; perfection is only achieved through elbow grease and TIME and effort spent on your craft ... apparently, everyone else that gave you such glowing comments is just as ignorant as you - NOT claiming to be an expert at everything, but I wouldn't make a video unless I REALLY knew what I was doing was presented in the most PROFESSIONAL way possible - other than than that, 73! - NOT 73s, sorry again, but THAT is incorrect too!
@edwhitney186211 ай бұрын
Oh. I don’t claim to be an expert. I have soldered that way for many years with good results. Time for you to make a video! Take care. -Ed
@hugh00711 ай бұрын
No callsign?
@radioguy1951011 ай бұрын
Liked the video however, you could added one more relay and a couple of capacitors and RF chokes and made a phantom power supply to send 12 Volts to the relay instead of a dedicated cable and you would have been able to have three antennas off of 1 cable. But I am sure that you know that. 7 3 DE: KF0XO/EA4
@edwhitney186211 ай бұрын
Hi Radio Guy. Great idea! You’ll have to send me your design. I was trying to keep it simple but would love to make a video with your design! My email is good on QRZ. Thanks! -Ed. W8EDW
@VoeViking11 ай бұрын
Why not send the 12 volts over the coax and use a dc block near the radio?
@edwhitney186211 ай бұрын
Hi Voe! Yep, great idea. My next video is us building a Bias T together. Thanks so much for watching and the good suggestions! -Ed W8EDW