AD-25M - Would this work?

[Gilligan]

I want to put a (fairly lightweight) mobile-mount dual-band antenna on my handheld Pro-97 scanner. I recently made a post and asked for ideas. Now I've found an adapter on the net and I need the opinions of the experts.

My scanner has a BNC style connector and I can provide a BNC/SO-239 adapter like you would use to connect a mobile antenna to the scanner. Picture here.

The antenna of choice is a dual-band VHF/UHF antenna w/ excellent gain on UHF (which is why I want to use it). It requires an NMO mount. This antenna pulls in stuff from all over the place. I just don't want to drag around the stupid mag-mount and all that cable. No, I'm not currently worried about the stress on the scanner's BNC connector. Picture here.

What I want is something that can mount that antenna onto my Pro-97. Found the AD-25M antenna adapter on hamcity.com for $14.95. Looks like it will actually convert the SO-239 into an NMO mount. But I'm concerned that there might be a connection issue or a grounding issue that I'm not aware of. Is there anything I might be overlooking? Picture #1 here. Picture #2 here.

Thanks for any help and advice.

 

[N1GTL]

Unless I am reading this wrong, you want to put the NMO mount antenna right on top of your scanner?

While I have never seen that done, I don't see where there would be a "connection issue" as you put it. As long as you have contact from the center pin of the bnc on the scanner to the antenna whip, it should work. As far as grounding, when you talk about antenna grounds, you are really speaking about the "ground plane", not a power ground. If you mount an antenna on a vehicles roof, that roof is your ground plane and the roof is the best spot for an antenna. However, putting that antenna on your scanner directly, you will have no ground plane to speak of. You mention how that antenna works great but how do you know that? If you have used it on the car, with a ground plane, you cannot expect the same results with that antenna connected right to the scanner with no ground plane. Handheld scanners come with rubber duck antennas and they certainly have no ground plane.

 

[rankin39]

Use a half-wave.

All handheld antennas are compromises, since they generally lack a ground plane. The advantage of a half-wave antenna (over a quarter wave or 5/8 wave) is that it doesn't require a ground plane in order to work properly. You can get any number of good dual band antennas that have a SO-239 base. It seems to me that an NMO would be awfully cumbersome to mount on an HT. There are also a number of telescoping HT gain antennas that have BNC bases. I think if it were me, I'd just save up and buy one of those.

Bob, w0nxn

 

[SAR923]

Unless I'm missing something here, the first adapter converts a BNC adapter to a female SO-239. The other adapter converts a male SO-239 to an NMO mount. You still have have at use least a jumper from any antenna to get to the female SO-239 mount on the radio and I don't see how the antenna is going to stay on the radio. The Diamond RH77 has gotten rave reviews from users and it's a lot less expensive and complicated compared that what you are proposing. Why wouldn't this work for you?

 

[Gilligan]

Unless I'm missing something here, the first adapter converts a BNC adapter to a female SO-239. The other adapter converts a male SO-239 to an NMO mount. You still have have at use least a jumper from any antenna to get to the female SO-239 mount on the radio and I don't see how the antenna is going to stay on the radio.

From the pictures, it seem that the AD-25M actually converts a female SO-239 into an NMO mount (not a male SO-239). I might be wrong, though. Some antennas apparently mount onto a female SO-239 mount, so that would make sense for the converter to do such a thing.[quote-SAR2401]The Diamond RH77 has gotten rave reviews from users and it's a lot less expensive and complicated compared that what you are proposing. Why wouldn't this work for you?[/quote]I am looking into this. I can't help but think that having a dual-band antenna would not be as selective as a single-band antenna on UHF, but it may be the only way to go to get a quick and easy BNC whip w/ gain.