What is a good scanner antenna (to include 2m and 70cm)?

[MikeSD]

I have a HomePatrol 1 and BCD396XT. I've noticed a lot of noise and static (relatively speaking), when listening to 2m and 70cm, compared to listening to the same frequencies on an amateur radio. I also notice a lot of pickup of computers noise. The main problem is the scanner antenna doesn't seem well suited for 2m and 70cm bands. Side by side comparison between my scanner reception and my amateur handhelds are significantly different. The amateur reception is far superior.

What type of antenna might I use, that would improve the reception on those bands, without significantly reducing the effectiveness on other scanner frequencies? I guess the obvious choice might be a dual band 2m/70cm. But I don't know how that will affect general scanning.

Anyone have any good suggestions? This would be primarily for my fixed base scanner. I most likely would stay with an indoor antenna.

 

[zz0468]

I seriously doubt that the antenna is the issue. The real problem with scanners, and the reason people have the perception that amateur or commercial radios receive better is because the synthesizers in scanners are noisy. The phase noise performance is compromised because of the need for rapid frequency changes, and they tend to have a lot of spurious signals on the output, as well.

The end result is a receiver that sounds like it's not quite sensitive enough, even strong signals never fully quiet, and they have a propensity for receiving strong off-channel signals.

This is why, in a side by side comparison, a scanner will always come in second to either an amateur radio, or a commercial radio.

 

[MikeSD]

I seriously doubt that the antenna is the issue. The real problem with scanners, and the reason people have the perception that amateur or commercial radios receive better is because the synthesizers in scanners are noisy. The phase noise performance is compromised because of the need for rapid frequency changes, and they tend to have a lot of spurious signals on the output, as well.

The end result is a receiver that sounds like it's not quite sensitive enough, even strong signals never fully quiet, and they have a propensity for receiving strong off-channel signals.

This is why, in a side by side comparison, a scanner will always come in second to either an amateur radio, or a commercial radio.

Ok, I can buy that, as "a" problem. But how come, then, that close signals sound very good and further signals sound bad? The explanation you give above, would seem to affect distant and local stations the same. The problem I'm having is with receiving distant amateur repeaters.

I don't have any problems with local stations. My problem is with amateur repeaters that are 20+ miles away.

Are you suggesting that there is no better antenna, for 2m and 70cm, than the stock antenna?

 

[zz0468]

Ok, I can buy that, as "a" problem. But how come, then, that close signals sound very good and further signals sound bad?

That's going to be true with any radio. I thought you were making a comparison between a scanner, and an amateur radio. Perhaps I missed something. How do the two compare using the same antenna?

The explanation you give above, would seem to affect distant and local stations the same. The problem I'm having is with receiving distant amateur repeaters.

Yes, it would impact all signals, but it could be especially noticed on weaker signals that are less than saturating the receiver. Keep in mind, also, that scanners are quite a bit less sensitive than the typical amateur band only transceiver.

I don't have any problems with local stations. My problem is with amateur repeaters that are 20+ miles away.

Then you may simply be asking too much of an indoor antenna on a cruddy receiver. A better grade receiver is going to be more tolerant of weaker signals delivered to it by a cruddy antenna.

Are you suggesting that there is no better antenna, for 2m and 70cm, than the stock antenna?

I didn't mean to imply that. A good quality antenna outside will be better than the stock antenna inside. As to inside antennas, I can make no recommendations. In my experience with scanners, they have been close to useless on signals 20+ miles away, when used with ANY type of indoor antenna. My initial impression of your question was a comparison between several radios, and the amateur radio sounds better. It's simply because it's a better receiver. You could put the best antenna in the work on the scanner, and the amateur radio will still be the better receiver.

 

[W2NJS]

In terms of sensitivity, the scanner must cover all frequencies from A to Z, where the amateur/commercial receiver for 2M and 440 is built to cover A to C and T to V. Design compromises are required, and the result is that the scanner covers everything in its wide range "okay" but not all that great.

 

[zz0468]

In terms of sensitivity, the scanner must cover all frequencies from A to Z, where the amateur/commercial receiver for 2M and 440 is built to cover A to C and T to V. Design compromises are required, and the result is that the scanner covers everything in its wide range "okay" but not all that great.

This is true, which makes the front end 'not so hot'. But it's the synthesizer that makes everything sound so 'hissy'.

 

[popnokick]

MikeSD- I am interpreting your question as follows:
- You're trying to pick up distant repeaters on your scanner
- You're using an indoor antenna and want to stay with indoor antennas

A 2M beam will work indoors, but it's pretty clunky and the pointy ends are dangerous. If anyone else lives with you, fuggedaboutit. 440 UHF beams are smaller, but same problem with the elements getting in the way of life in the kitchen/living room/bedroom. What you need is a practical antenna that will pull in more than the rubber duck on your scanner.

READ THIS THREAD: http://forums.radioreference.com/an...3-off-center-fed-vhf-uhf-vertical-dipole.html

Off-Center Fed Dipoles are dirt simple and cheap to build. For the $ and effort spent they have few if any peers in performance, particularly for what you are trying to do. Can you get into an attic or crawlspace with it? If not, make one out of wire using a 300 to 75ohm TV matching transformer (as is shown in the thread) and hang it from a curtain rod in the highest window you have. Two things are going to help your indoor antenna do the best it can: height and nothing more than a pane of glass between it and the great outdoors.

Spend the $8 and 30 minutes of your time to build an OCFD. It's fun and you'll like the result. Then come back and tell us how it worked on your handheld scanner.

 

[n5ims]

I have a HomePatrol 1 and BCD396XT. I've noticed a lot of noise and static (relatively speaking), when listening to 2m and 70cm, compared to listening to the same frequencies on an amateur radio. I also notice a lot of pickup of computers noise. The main problem is the scanner antenna doesn't seem well suited for 2m and 70cm bands. Side by side comparison between my scanner reception and my amateur handhelds are significantly different. The amateur reception is far superior.

What type of antenna might I use, that would improve the reception on those bands, without significantly reducing the effectiveness on other scanner frequencies? I guess the obvious choice might be a dual band 2m/70cm. But I don't know how that will affect general scanning.

Anyone have any good suggestions? This would be primarily for my fixed base scanner. I most likely would stay with an indoor antenna.

You could try using a dual band ham antenna on your scanner. There are several you can select from and they're available with your choice of BNC or SMA mount to match the scanner as well. One example is the MFJ-1717 (MFJ Enterprises Inc.) which has the BNC mount while the MFJ-1717S is the same antenna with the SMA mount.

What I use at times is my Larsen NMO 2/70C on a mag mount stuck to a large file cabinet. The file cabinet makes a pretty good ground plane and keeps the antenna out of the way. Larsen Amateur Mobile Antennas NMO 440B has the antennas and for the mounts Larsen Amateur Mobile Antenna Mounts NMOMM, NMOMMR, NMOTLP, NMOK, TLM

 

[eaf1956]

My Icom 746 will pick up VHF police freq where my scanners on the same freq are quiet. But then the 746 is a much higher priced radio and not a scanner.

 

[oldmanonavtx]

what is a good scanner antenna

There is a lot of things to consider while trying to receive any station on a ham radio or scanning receiver. Ham radios most of the time do receive better on the ham bands than a scanner. I will say that you do not have a cruddy receiver as some stated. I have had scanners and ham radios for twenty years. Most of the scanners I have had nearly always receive as well as my ham handhelds. They both have their limits. The antenna and your location always make a difference. Some of the static you are receiving on ham repeaters could be from the station trying to make it into the repeater. They are on the fringe of the coverage area and either do not have enough power, antenna or are to far away to get a signal into the repeater. Your location and whats between you and the repeater also makes a difference. I use a diamond srh77ca with good sucess on both my scanners and ham handhelds. All store bought or home made antennas are not equal so you have to see what works for you. I receive 2meter repeaters as far as 40-50 miles on my pro 106 and 330t with the srh77ca. Most antennas that come with ham handhelds are not very good. I have had several out of the box that would not reach ten miles on five watts, and no I'm not in a cave. Try to experiment with making some home made antennas and see if you can make something that will be better than others. Dual band antennas will help with vfh and ufh coverage and a lot in between. You can build some simple beams that will help with vhf and uhf and be better than rubber ducks. I have had good sucess with a 4 element quad for 2mtr and 70 centimeters. Antennas can be made of most any thing from bed springs to barbed wire fence and stuff in between. Experiment. All you can be out of is some so-239's and a little wire from what ever. Even have a small beam made from a broken luftkin ruler. You will have to keep your scanner a couple feet away from the computer so you don't pickup the noise. Put your antenna in the attic if possible.Some tv ladder wire is not that noticible outside.

oldmanonavt