Antenna's and accessories, oh my!

Started by Genken, September 06, 2012, 01:27:24 am

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So, I've had my Tech license for awhile, just no money for a radio. Well, soon to change. Now I am looking at accessories such as antennas, and my mind is blown.

The radio I've chosen to get is the Yaesu FT-857D. I plan on getting my General this weekend with my buddy who also has his tech while he is in town.

I've read the review on the Diamond Supergainer, so I went to look up those. Found the Diamond HV7A.   I'm also looking at picking up the Diamond HVC14 (20m Add-On) and the Diamond HVC7 (40m Add-On).

Seems simple enough, except I know that the FT-857D has 2 antenna connectors on the back for HF and VHF/UHF. So, looking at related products for the HV7A, it's got a Diamond MX62M listed.

Now, what exactly is a duplexer, and what would I need it for? Best I can figure, hook it up to both ports on the radio, and I can switch between HF and VHF/UHF without changing cables

My other option, is to build my own, except last thing I want to do is fry my radio because I messed something up.

Let me go ahead and state my intended purpose for this radio. I'm going to set it up to be an all-in-one super rig. Home Base station, Car rig, and a manpack configuration in my ruck. I've got a rough idea how I'm setting the power up for the manpack mode(as well as charging), as well as working QD methods to switch between them all in a hurry. I figure I can work a rig to use the same antenna in the manpack configuration, adding the add-ons when switching bands.

My buddy is also getting one of these radio's, and if the need arises we will be able to communicate with each other as we are on the move.

So, I guess my condensed questions are, is this a good antenna setup, and would a duplexer be a good investment?

I appreciate any help.



September 06, 2012, 07:45:52 am #1 Last Edit: September 06, 2012, 07:49:06 am by cockpitbob
Antennas are one of the more (wonderfully) maddening things in ham radio.  Antenna performance is often more important than the radio's performance and there are a zillion options to choose from.

I also have an FT-857D for the same reasons that it's a good compromise between base and mobile.  For a base antenna I simply have a 180' long end fed wire that I feed with a manual tuner.  My shack is by the basement wall so I have only 15' of coax going to the antenna and a ground rod.  I have a bead balun on the coax.  Performance is a compromise, but it is a cheap setup and gets me all the HF bands except 160M.  I do very little mobile, so I just have 20M and 40M hamsticks and a mag mount 2M/440 antenna.

Yes, the duplexer allows you to use an HF/VHF antenna without a switch.  It is basically 2 filters, one for HF and one for VHF frequencies, that steer the signal into the correct connector on your radio.  Personally, I would use 2 antennas on the car.  It would eliminate the duplexer so cost would be about the same and performance would probably be better than with all the compromises needed to make an antenna covering HF and VHF.  The first thing I would do is check the reviews on to see how people like that antenna. 

For manpack operation you're going to get tired carrying the battery.  The FT-857 draws about 0.65A in receive.

Good luck getting your General!



There's always more than one way to 'skin a cat', and antennas are no exception.  The reason why there's two antenna connections on that radio is so that you don't have to change cables when going from HF to VHF/UHF.  And since there are very few (or make that very few 'less expensive') all band antennas that are even remotely portable, using more than one is a fairly 'smart' thing to do, you know? 
Which antenna to use depends on what you want to accomplish.  Antennas range from super simple to "what the @#$$ is that!".  Making those antennas (the simple ones) isn't as difficult as it may seem.  It does require that you have -some- knowledge about antennas, but you don't have to be an 'expert' by any means.  What you can do with one antenna can usually be done with a length of wire and a means of matching input impedance. 
I can't say anything about the particular antenna you mentioned, I've never owned/used one. 
Good luck.
- Paul


As far as the antenna, I don't mind running 2 on the car, but when it's in my ruck I don't want to deal with multiple antennas sticking out. I've ran multiple radios out of my pack when I was an rto, and keeping track of 2 long whips was never fun, especially when trying to move and keep my LT and myself behind cover. The duplexer would mainly be for the manpack. I'm trying to keep it modular if possible. Should be a fair tradeoff.

As far as the weight, rucking isn't anything new to me, especially with lots of weight. I'm still in the army (infantry)  so plenty of pt for me.

To help negate current draw and for general recharging im thinking about one of the flexible solar panels and a small charge contoller. I can easily rig the panel onto the ruck.

And I already looked for reviews at eham, and nothing there for that model. I will look more into it in the next few days, but as of right now its looking like what I'm wanting.

Thanks again guys.


Instead of the flexable solar panel you might look at some of the thermoelectric options talked about in this thread here on radiopreppers.  One is a cook pot that generates electricty while you boil your coffee water.  The other is a tiny wood stove you can use to heat stuff while it generates electricity. 


Quote from: Genken on September 06, 2012, 03:08:20 pmTo help negate current draw and for general recharging im thinking about one of the flexible solar panels and a small charge contoller. I can easily rig the panel onto the ruck.
Your charging solution doesn't fix your current draw; reducing power would or in some cases getting to know the rig and turning off the little tiny things that can add up.

Example: My 817 has 2 outputs, but they can be assigned by band to go out the SO-239 in back or the BNC in front. In the field for HF I run everything out the front - because there is a notable current draw penalty just having that SO-239 enabled. So get to know your rig.

If you're an 11B you well understand when someone hands you something "new & lightweight" that 100lbs of lightweight stuff is still 100lbs. Folding panels & lighter weight gel cells using a 3:1 duty cycle can last quite awhile if you're not pumping full power all the time.

Even if you don't buy from them (no affiliation here) try this link:
Check out

They have some things & expertise that might interest you; you just have to nug out the numbers and don't be afraid to pickup the phone.

For field use I'd recommend simple wire antennas; more room for your other "lightweight" stuff. Your chosen 857 is one of those that has 2 outputs assigned for their different roles, so I don't see the need for an antenna duplexer. Not all radios are like that; not all in fact even have 2 outputs to begin with. You are blessed.

There's some other good experience here, they can chime in. But I will say that every GOOD mobile signal I've ever heard - when asked - said they were VERY particularly about proper & multiple grounds and that was as, or more, important as the thing sticking up in the air.
Good luck.

White Tiger

Maybe I should have posted this BEFORE attempting to erect my antenna mast...but let me city that now!

I bought a package of ten, 4' fiberglass military poles (typically used for mosquito netting for military tents, I think), to use for my 80m-20m fan dipole. Last weekend I had everything in place...assembled the masts, guyed it at 28' did a "dry run" - meaning That the first time I set it up I did it without attaching the home-brew masthead (which I had duct taped a pulley to winch-up the center coaxial feedline) far so good.

Then I attached the home-brew masthead...and my son and I started "walking" the 40' mast "up" to it's standing (23 y/o son kept saying "Dad, are you us you know what you're doing, this sure doesn't seem to be working..." ...And then "Dad, I think I hear a cracking sound...")...

...many of you are probably cringing right now...if so, you won't be as surprised to hear that two of the fiberglass poles eventually snapped at the my 40' mast is a 32' mast until my second bag of poles arrives....

So, my question to any who have used a similar set-up: how exactly is this supposed to work?

If you're looking for me, you're probably looking in the wrong place.


Hello Tim,

I would not have tried to walk that up... Rather assemble the elements one by one while pushing the mast straight up, one piece at a time..


White Tiger

See...I should have asked!

Not sure how to guy it that way?
If you're looking for me, you're probably looking in the wrong place.


Attach the guy wires to the mast first, make sure they're long enough, let them dangle as you push the mast up, and then secure them to the ground after the mast is up...


White Tiger

...that is awesome...

...and only slightly demoralizing! ;-)
If you're looking for me, you're probably looking in the wrong place.


October 06, 2012, 02:43:04 pm #11 Last Edit: October 06, 2012, 06:16:37 pm by raybiker73
That's how I put up my mast, from the bottom up with the guys loosely attached. I did a little extra to make a semi-permanent mount. The bottom of the mast is 2-1/2" OD, so I dug a hole and cemented in a length of 3" OD PVC. The bottom of the PVC goes into the dirt below the cement to allow for drainage, and I installed a small grate on the inside of the pipe to keep the mast out of the dirt by a few inches. I also drilled a few holes in the above-ground section of PVC to allow for winter expansion - I don't want anything to freeze and crack. Since the line to my house is buried, I cemented in a second PVC fitting beside the mast. Below ground is a 3" T-fitting. The "up" end has a length of pipe with a cap, into which goes the antenna line (seen in the picture). The "down" end is open to the dirt, both to allow for drainage and access to the ground rod for the lightning arrestor that's in the pipe. The other part of the T, of course, goes to the house. It was a pretty cheap project: about $15 worth of PVC/fittings and one bag of Sakrete, and it only took about an hour (not including drying time).

EDIT: fixed typo.

White Tiger

Hey Ray, that is a nice set-up!

If you have any further pictures of your project, I'd love to see 'em!
If you're looking for me, you're probably looking in the wrong place.


Quote from: gil on October 05, 2012, 11:11:57 pm
Attach the guy wires to the mast first, make sure they're long enough, let them dangle as you push the mast up, and then secure them to the ground after the mast is up...


How will you keep from running into the guy wires while mowing?


You don't mow anymore of course, that's out of the question until at least the weeds reach the dipole itself...