Duplexer...

[K9CCH]

What would a duplexer on a UHF/VHF be used for?

[K7SGJ]

For combining a uhf and a vhf radio to use a single feed line for a multiband antenna. They are also available to combine a HF output with VHF and UHF radios (Triplexer) to run everything down one coax for a multiband antenna much like you would do in a mobile situation where you don't have an antenna for each band.

My 857 has the option to run HF +6 Meters out one jack, and the UHF/VHF out another jack, (it has a built in selectable duplexer) or you can select the option of running everything out one jack if you are using the ATAS 120 or equivalent. I have it set to run HF/6 to the ATAS 120, and VHF/UHF to a UHF/VHF antenna because at times I only use the VHF/UHF portion of the radio.

[NQ6U]

What La Rata said.

At Field Day last year, we used a triplexer along with some bandpass filters to allow three people to share a single tri-band Yagi—each on a different band, of course. It worked quite well, even if it did mean that all the work I put into building my 15m Moxon turned out to be for naught.

[XE1/N5AL]

^^^But who got to "drive" the Yagi?

[WØTKX]

Hmmm. AFAIK, the FT-857 does not have a duplexer built in.

You have to install an external one to use a single feedline on an ATAS-120.

Moot point. Duplexers are about $70, triplexers are about $10 more.

[K7SGJ]

Hmmm. AFAIK, the FT-857 does not have a duplexer built in.

You have to install an external one to use a single feedline on an ATAS-120.

Moot point. Duplexers are about $70, triplexers are about $10 more.

You are correct, there is a menu setting that tells the radio the ATAS 120 is being used for 1.8-440 so it will tune the antenna properly, unless the VHF/UHF is going to a separate antenna. But you do have to use a diplexer to combine them onto one coax when using the ATAS for all bands.

[K9CCH]

I posted a WTB thread on the swamp for a VHF/UHF radio and someone locally replied. He has a Kenwood TM 733A with a Diamond duplexer for sale in original boxes. Wants $200 for the kit.

I knew it had something to do with multiple feeds, I just didn't know exactly what it was for.

[WØTKX]

That's not a bad deal. I like that radio, almost bought one.

[K9CCH]

That's not a bad deal. I like that radio, almost bought one.



I bought that FTM350AR for $450 or $500 and it was WAY too much radio for me, even though it was quite a pretty radio. So I figured I'd put something cheap and easy in the Jeep and start back at the basics and grow from there to see how much I use it.

If I find myself using it a lot, and moving forward again with the hobby, then I'll look at upgrading later. I dont need all the bells and whistles right now.

So this 733A is used, and I'm trying to decide between it, or a Yaesu FT2900R.

[K7SGJ]

I posted a WTB thread on the swamp for a VHF/UHF radio and someone locally replied. He has a Kenwood TM 733A with a Diamond duplexer for sale in original boxes. Wants $200 for the kit.

I knew it had something to do with multiple feeds, I just didn't know exactly what it was for.

That really is a very good price for that radio, and I believe it has cross band repeat on it which can be useful.

[NQ6U]

^^^But who got to "drive" the Yagi?

Nobody. One interesting thing about living in the extreme southwestern corner of the US is that 90% of potential Field Day contacts are more or less on the same beam heading.

[K9CCH]

Decisions decisions....

Would you buy a,

-Kenwood 733A with duplexer and separating kit for $200
-Yaesu FT7800R with separating kit and Lido floor mount for $200
-Icom V8000 for $100
-Yaesu FT2800m for $95.

I'm leaning towards the 2800 because it's the cheapest, or the Kenwood because of the dual band cross band repeat.

The Kenwood is opened up to TX wherever it receives.

[K7SGJ]

If it will get beat to shit in the Jeep, or stands a good chance of getting ripped off, go cheap. If it will be secure, and you think you will use the xband repeat, the Kenwood is a good buy. I use the xband repeat around here, because there are too many mountains and I'm too far away for most of the repeaters in Phoenix or northern AZ using a handheld. I mostly use xband on the swap net on 144. With a 50mw handheld going through the Yaesu FT8900 in xband mode, running high power to the multiband antenna, I can hit most anything.

[K9CCH]

The only reason I could ever see myself using cross band was if I were at the beach and wanted to walk away from the jeep with my baofeng. Or if I want to talk with the baofeng from inside my house. But then I have a J pole on the roof so that is a moot point.

I'm thinking about going with the 65w $95 option, and saving the rest to put towards an HF setup.

65w would allow me to hit all the 2m repeaters around here just fine.

[K7SGJ]

good choice