base scanner antennas

[KD6HRI]

I am looking for some input about a good base scanner antenna to get that is reasonable in cost. I'm mainly monitor 800 mHz systems, but I would like it to be a good choice for other bands as well. Your thoughts are greatly appreciated!

 

[samsat]

I used a discone for years. When tuned right you can transmit on 2m and 70cm.

 

[jbantennaman]

The problem with 800 Mhz is that it is such a short wavelength, the receiver becomes very finicky unless the antenna is resonant. The problem is that loss plays a role and even RG 6 quad shield becomes very lossy at lengths of more then 50'.
I guess if all you want to listen to is local traffic, which can be received with a handheld, then any antenna and coax will work. But if you are trying to receive signals from 30 - 50 miles away - forget it.

Cheap and good don't walk hand in hand when it comes to antennas and reception.

If it was amateur radio, I would invest in a good base station antenna, a Diamond X510 is a great antenna from a reception standpoint, as long as you buy one that uses an N connector, not a PL connector. PL connectors are not designed for use on UHF frequencies and they have an impedance bump around 300 MHz..

If all you want to listen to is 800 ish UHF you could probably try to use a UHF television antenna, although television antennas are designed for frequencies between 300 and 700 Mhz, so the antenna would be too long for good reception of 800 mhz, but if the signal is strong enough, even an old coat hanger will receive something.

 

[Token]

If it was amateur radio, I would invest in a good base station antenna, a Diamond X510 is a great antenna from a reception standpoint, as long as you buy one that uses an N connector, not a PL connector. PL connectors are not designed for use on UHF frequencies and they have an impedance bump around 300 MHz..

The X510 is not available with a "PL" connector. The X510 can be had with N type or UHF type connectors. My assumption is you are calling the UHF type a "PL", however it is an SO-239 that is on the X510, not a PL anything. A PL-259 is what would be used to connect to the SO-239 UHF style connector of the X510.

There is no doubt that at frequencies above 100 MHz N type is better than UHF, however many radios come with UHF connectors installed up into the 500 MHz range. There are measurable differences between UHF and N type connectors on 70 cm, but personally I find that in real world FM audio application it is essentially impossible to tell the difference between a quality UHF connector and an N type connector up to about 70 cm. Sure, if you are doing weak signal work such as EME or terrestrial SSB / CW it is worth the effort, but generally not for FM.

For sure I would never push a UHF type above 70 cm, and in general most of my stuff above 100 MHz is N or SMA type, but that does not make UHF type unusable for many applications in the VHF and UHF range.

T!

 

[chief21]

I've read some good comments about scanner antennas from DPD Productions...

DPD Productions - Base & Mobile Antennas for Radio Scanners: VHF, UHF, NOAA, Low-Band, 700 MHz, Police, Fire, Public Safety

Not too many other scanner-specific options since the ST-2 Scantenna was discontinued.

John

 

[gonefishn1]

If you want a great scanner 800Mhz antenna then look at the 800Mhz Yagi antennas. I just aim mine at the repeater site and it works great from 50 miles away. Amazon has plenty to choose from.

 

[trp2525]

I am looking for some input about a good base scanner antenna to get that is reasonable in cost. I'm mainly monitor 800 mHz systems, but I would like it to be a good choice for other bands as well. Your thoughts are greatly appreciated!

...Not too many other scanner-specific options since the ST-2 Scantenna was discontinued...

There is currently a brand-new Radio Shack version of the ST2 Scantenna available on eBay for a starting bid of $129.95 or "Buy It Now" for $169.95 (plus shipping): BRAND NEW RARE BASE SCANNER ANTENNA | eBay

FYI the Radio Shack version of the ST2 has blue insulators while the Antennacraft version has black insulators. AFAIK the antennas are otherwise identical. Considering that the ST2 scanner antennas have been selling for $200-$300+ on eBay, I guess this pricing is "reasonable in cost" in comparison.

 

[jackj]

If you are talking about receive only, check out discone antennas. Cheap, wide band and robust. If you need it for transmitting, cheap and wide band don't apply.

 

[jafarm66]

I would use the Diamond D130J or D130NJ both are discone antennas which can be outdoor or even indoor hung from your ceiling if you live in an apartment or condo. I only use them for scanning receiving.

I have no idea if you need to transmit but I think this antenna can though I am not sure and you should check with seller.

Reception on it is excellent. I have the D130J.

 

[ko6jw_2]

I have been experimenting with a Diamond D130NJ for a few months. When considering discone antennas there are several things to keep in mind. The first is that, although Diamond and others state that the coverage on these antennas is 30-1300Mhz, this is a gross exaggeration. The discone part of the antenna covers roughly 110Mhz to 1200Mhz. The low band coverage on the Diamond is set at about 50Mhz. Thus, the claim that it can be used on 6 meters. The low band coverage is a base loaded ground plane - not a discone. Bandwidth at 6 meters is maybe 4Mhz at best. You must physically tune the whip to get a low SWR on 6 meters. What if you want to monitor 42Mhz (Highway Patrol in California)? The stock performance will be very poor and the SWR very high. The solution is to get a longer whip. With a 48" whip it tunes at 42.5Mhz. The whip is .1 inch and can be obtained from many sellers.

Discones can transmit. The Diamond can do 6 meters, 2 meters, 1.25 meters, 70 centimeters, 900Mhz and 1.2Mhz. The SWR will be low on all those bands (must tune whip for 6 meters).

Order the version with a N connector. It will perform much better the the SO-239 version at UHF.

These antennas have no gain. If you need gain look elsewhere. They are extremely broadband. In the 110 to 512Mhz range mine is <2:1 SWR.

By the way RG-6 is often mentioned in these threads because it has "low loss." However, it is 75 ohm coax and the discones are 50 Ohm and so are most radios. Use the best quality 50 ohm coax you can afford. LMR 400 or RG-213 etc.