Diplexers - Connecting Several Transceivers to One Antenna

Diplexers, often marketed as "duplexers," are a great tool for either connecting several transceivers to one antenna or several antennas to one transceiver. See how I've managed to use just one antenna to serve four transceiver ports.
Featured in this video:
Comet CF-360B - www.dxengineering.com/parts/c...
Comet CF-4160J - www.dxengineering.com/parts/c...
Comet CF-706A - www.dxengineering.com/parts/c...
My Amazon Storefront: www.amazon.com/shop/stealthgti
Mods to the car and links to blog write-ups:
IS38 Turbo with APR Programming, Downpipe and Intercooler - wp.me/P7YnQB-dP
RSR Clutch w/DMF by HS Tuning - wp.me/p7YnQB-su
Baun Performance Catback Exhaust - wp.me/p7YnQB-1KJ
Lots of Electronics - stealthgti.com/electronics/
EcoHitch by TorkLift - wp.me/P7YnQB-hW
Gun Metal Gray Nogaro Wheels - wp.me/p7YnQB-Dg
Various Accessories - stealthgti.com/accessories/
My Camera Setup:
GoPro Hero 9 Black - amzn.to/2MoJ2h1
GoPro Media Mod - amzn.to/3r3zmHw
Canon 90D Video Creator Kit - amzn.to/3rcGLEA
Rode VideoMic GO (at home) - amzn.to/2RyOYnk
Rode VideoMicro Compact (in the car) - amzn.to/3kmnput
Rode Wireless GO Adapter - amzn.to/3aVAg3z
Rode Lavalier GO Professional - amzn.to/2RXDCMv
ZOMEi 75'' Tripod - amzn.to/3aRYBFl
Neewer Camera LED Video Light - amzn.to/36Dbznc
Studio Lighting - amzn.to/36uEycM
Glide Gear Teleprompter (for long videos) - amzn.to/3hIABXo
Galaxy Tab S4 (for Teleprompter) - amzn.to/33BwRlE
Visit me at StealthGTI.com.
Visit my Instagram page at / stealth_gti
DISCLAIMER: StealthGTI is a participant in the Amazon Services LLC Associates Program. As an Amazon Associate, I earn a small commission from qualifying purchases if you purchase a product with a link that I provide. There is no additional charge to you!

[@bthemedia]

Appreciate the ham radio content… as well as how power and cables are run through the GTI! 👏👏👏

[@StealthGTI]

I'm glad you find the content helpful! Thanks for watching!

[@Clint_L]

Love it Scott. As a fellow 12v electronics fan love seeing your integration in the GTi. Great work as always my friend. Love the evolution of your channel.

[@StealthGTI]

Thanks 👍 It's still evolving, too. Each coming video seems to show more things that I'm stuffing into this little car! LOL!

[@reidlanham2011]

Great video to go along with your great installation!

[@StealthGTI]

Thanks! 👍 I appreciate your comment!

[@KA9DSL]

Glad you know the what a diplexer is, a lot of hams don't no the difference! (they would call it a duplexer)

[@StealthGTI]

Thanks! It doesn't help that the manufacturers market and sell them as "duplexers." I'm not sure why they do that unless it's a language issue (most are Japanese units). Thanks for visiting!

[@KA9DSL]

@@StealthGTI I think it's hype, makes the part sound very important. But you and I know better.

[@BottomleyAdventures]

Interesting setup, the only negative I see is the (likely substantial) amount of loss from all of those cables and connections, especially on UHF.

[@StealthGTI]

Agreed! At the time, my priority was to hide the fact that I'm packing ham gear by minimizing my antenna count. Today, my setup is far more conspicuous and has more antennas. See my channel's main page for more info. It's a bit insane. Thanks for visiting!

[@ec8azc]

Beautiful

[@StealthGTI]

Thank you! Cheers!

[@alvarogaitan2529]

Another fantastic video thanks 73 from kb2uew

[@StealthGTI]

Glad you enjoyed it! Oddly enough, my recent overhaul removed this setup. I'm working on its replacement now. Having NINE antennas mounted has expanded my options. HAHA! Thanks for visiting!

[@M9A1MAN]

Two radios, one vhf and one uhf. Using this with a single dual band antenna, can I transmit at the same time on both radios? Reason I ask is I’m going to use the vhf for aprs so it may beacon while I’m on uhf

[@StealthGTI]

I THINK it will work. Well, I know they'll both transmit. What I don't know is whether the receivers are exposed to anything at the time. Send an e-mail to Comet. I found them to be very responsive to technical e-mail questions. Let me know what they say. Thanks for visiting.

[@bGlennjamin]

Dig the ham radio content!

[@StealthGTI]

Thanks!

[@neolinux]

Do you have a Diagram of that build?

[@StealthGTI]

No diagrams, unfortunately. I sort of pulled a "mad scientist" execution to make things work. These days, though, I have enough antennas on the roof that I no longer need this network of diplexers. Instead, I have them spread out in different ways to cover more bands and more radios. Thanks for visiting!

[@illiteratebeef]

So many adapters, so much loss. It would be illegal (even if the FCC doesn't enforce it) to mars mod your ham radio and TX in GMRS, but it would remove so much loss. Maybe getting a part 90 radio that does all of 70cm so you can do both ham and GMRS on that legally would allow you to use both in those rare times, but I don't know of any part 90 mobile radios that also does 2m. Anyway, cool to see. I haven't played with diplexers so it's interesting to see how you're using them.

[@StealthGTI]

I thought about the losses, too. The insertion loss is 0.2-dB per box (0.1-dB on VHF). The CF-706 is the worst, at 0.4-dB. The HF path loses just 0.2-dB before exiting beneath the car. Given my short transmission paths, I wonder if the 0.8-dB (max) is similar to what home owners might see with longer coax lengths. I honestly don't know. But I can say that I could not measure a difference in received FM repeater signals on the radio. That's not to say there are not losses... but I do not perceive them. Should I find myself contesting and looking to maximize my signals, I'd take the time to bypass all diplexers and use straight coax. I might even remove the CF-706 since its only purpose is to combine 6m with the rest. I almost never use 6m. Thanks for visiting.

[@troco4238]

And here i am with my tyt and a diamond quad band antenna 😢

[@StealthGTI]

HAHA! Check out my KE4WMF playlist. Things have gotten out of control since making this video. ;-) Thanks for visiting!