Smiley HH antenna help and ?s

[Haley]

I have decided to get a Smiley antenna and need a little advice. Two questions.


1. I need/want a specific HH antenna for railroad, and NOAA Dxing. So 160 or 165 as my center frequency? I do realize those are able to receive as well (according to their website) 5 MHz. on either side of that.

2. 5/8 commercial, or commercial duck? Am I right to assume the 5/8 would be longer no matter what? And would the difference be enough to have an edge over the other choice? I am trying to get something shorter than the Diamond (awesome antenna, just too long sometimes).

I should say I have dozens of antennas now, including the Diamond RHC77A. I was just looking for a shorter antenna that might give similar performance in that range. I will use the new antenna on several different radios if this matters. I own Uniden 396XT,346XT,125AT, and 246T. Radio Shack 51,92A,92B,96 and 106. An Icom R2, and a Kenwood THF6A (can't say enough about this little radios receive ability). I only list the radios hoping some one may have used any of the above combinations. Thanks for any help!

 

[LtDoc]

The one thing that will show the most improvement in reception if getting the antenna higher. Not too practical for an HT, or some base stations, right? Also, with most VHF/UHF antennas, 'bigger is better', meaning that combinations of antennas into arrays tend to mean better reception.
Short antennas mean less performance than bigger antennas. Making an antenna shorter than 'normal' always means a drop in performance and is -only- for convenience.
Since you are only interested in a faily 'narrow' range for frequencies, 160 - 165 Mhz, then I would 'lean' toward an antenna designed for the lower frequency limit, 160 Mhz. It would be slightly too big for 165 Mhz, but that's not a bad thingy.
The 'size' of an antenna is directly related to the length of a 'wave' at the frequency of interest. Then it's a matter of 1/4th, 1/2, 5/8ths, etc, etc. The bigger the 'fraction' the bigger the antenna. The 'biggy' in that is that the different 'sizes' have different shaped radiation/reception patterns. The longer the thing is the 'further' it will hear, sort of. Lots of other factors in that, but it's a fairly true 'fact'. And then, it just depends on how 'strong' a signal is to start with, or how far away it is. All VHF/UHF stuff is "line of sight", meaning that if two antennas can 'see' each other, they can probably 'hear' each other. Just like you standing on the ground can't see as far as if you were standing on top of a ladder.
There you go. Nothing 'scientific' about any of this, it's all a generalization. Want specifics, the 'why' of it all? Start studying...
- 'Doc

 

[Haley]

Thanks for the help! I went ahead and ordered the commercial duck at 160. I figured the 5/8 length would be close to the Diamonds anyway. So might as well try it first. And what the heck I may end up ordering the 5/8 later anyway! Thanks, Mike

 

[LtDoc]

Oh boy, here's some more radio 'fun'.
Antennas are typically measured in two ways, their physical length and their 'electrical' length. An 'electrical' length means that the physical length can be shortened by 'loading' the antenna, which just means putting a coil in it. A typical 'rubberduck' antenna is a 'loaded' antenna, it's way shorter than the normal physical length. It will 'work' but not as well as a full sized antenna.
For whatever reason, manufacturers are tending to use misleading names for their antennas. (Not all of them, but some.) For instance, some may advertise a 5/8 wave antenna but the thing is a loaded antenna so is much shorter than a full 5/8 wave length long. Sorry Charlie, that's not a 5/8 wave antenna and will not perform like one. An antenna's physical length determines it's label as far as 1/4, 1/2, 5/8, or whatever length it's touted to be.
So, for 160 Mhz a 1/4 wave antenna is about a foot and a half long. A 1/2 wave length is about three feet long, and a 5/8 wave is about three feet and 10 inches. Those three feet antennas get sort of unwieldy if you want to carry a radio in your shirt pocket, you know? So, how long is the antenna you ordered?
- 'Doc

 

[Haley]

I am learning a lot here! That's good, just don't know as much as I should about antennas. As far as the one I ordered, it says on the website between 5 and 12 inches. I just assumed it would depend on your center frequency. It actually shipped today. I will post about it when it arrives, I guess either way I will have a new antenna to play around with. Thanks for the information! Mike

 

[questnz]

Haley, Watson WSMA 801 will fit your requirements perfectly, excellent performance and much shorter than SRH77CA W-801 Regular Gainer BNC Portable Antenna

 

[Fast1eddie]

Appears very similar to the all band duck Radio Shack sells for $14 something, at least the last time I checked. A excellent performer!

 

[LtDoc]

You just can't 'shorten' an antenna without loosing performance, no matter what the advertising says. There are no 'miracle' antennas, period. The 'minimum' length for any frequency/bad is easy to figure, divide 234 by the frequency in Mhz and that's a 1/4 wave, the shortest resonant antenna with a predictable/expected radiation/reception pattern. That's not a very convenient length for some bands/frequencies, but anything shorter than that is also going to be 'short' in performance too. That's a given no matter what you want to think. There's a hell'ova difference between a minimum physical length and an 'electrical' length. That 'electrical length' makes the impedance matching easier, but impedance matching isn't what determines how well an antenna works. A receiving only antenna doesn't have the electrical requirements that a transmitting antenna has, but longer really is better.
Making an antenna shorter is only beneficial when you are thinking about convenience, period.
- 'Doc

 

[Haley]

Just thought I would give a bit of an update. Got the antenna yesterday, it's right at 7 inches. So far I've tested it on the Pro106,Pro96, BC125AT, and the Kenwood THF6A. And I can say without a doubt, it has improved my reception of the distant Wx stations, its center freq. is 160mhz. Normally I can receive 2, maybe 3 stations this time of year. Yesterday, and today (so far) I was able to receive 3 solid on the 125 AT, actually surprised me, thought this one might do a bit better on VHF than the others.

The 96 did fine on 3, almost could pull a fourth in. And the 106 with its HOT front end managed 5. Now for Kenwood, I do not have my amateur lic. I actually got this radio because I wanted something small and light for HF USB/LSB and possibly some VHF RR, and Wx listening. I am not as technical as a lot of people on here but I have to say this thing is unreal with the smiley. Picked up 6 Wx stations. Counting 2 stations that have the same freq. I sit halfway between them . 65 miles one way, 55 miles the other way. I know some may think I'm nuts using the Kenwood for Rx only. But it is more or less my emergency type radio. I am sure some of you would know but this radio, by design(?), must have much better rejection than any scanner. Because the kicker is, my local Wx station is literally out my back door here. I can see the tower as I type. I run into a lot of bleed over on the scanners depending on what antenna I have on them. Even with the ATT. on sometimes.

Anyway that's my first impressions of this antenna. I plan on testing it on the 346xt,396xt, and 246t also. Sorry a bit winded, but this might help someone. Mike