Diamond X300N

[rangers38]

I am thinking of buy a gain style antenna for my scanner. I pretty much monitor the 150 MHZ & 450 MHZ ranges. I know this antenna is not tuned to the 800 band, but would it recieve it as well? If not, is there a multiple gain style antenna that would recieve all 3 bands?

 

[prcguy]

That antenna is sharply tuned for the amateur bands and outside that the gain off rapidly, like 156Mhz or 464Mhz would be very reduced performance. Receiving 800MHz on it would be random and unpredictable.

I am thinking of buy a gain style antenna for my scanner. I pretty much monitor the 150 MHZ & 450 MHZ ranges. I know this antenna is not tuned to the 800 band, but would it recieve it as well? If not, is there a multiple gain style antenna that would recieve all 3 bands?

 

[rangers38]

That antenna is sharply tuned for the amateur bands and outside that the gain off rapidly, like 156Mhz or 464Mhz would be very reduced performance. Receiving 800MHz on it would be random and unpredictable.

I just want it to recieve. most of the frequencies are 155 range and 453-478. So would this work for that? I had a comet GP15 which picked up the 800 bank pretty well, although it was not tuned for that. Any recommendations? I have a discone now which i want to replace and do not want a wide band like that because the gain is so small

 

[prcguy]

The antenna will certainly receive there but if it advertises 6.9dB gain on VHF and 9dB gain on UHF within the amateur bands (both extreme lies) then expect much less, maybe half or less when you push the antenna very far from its design frequency.

There are commercial versions of some antennas like the Comet GP6-NC and GP-9NC which are factory tuned for 153-157MHz on VHF and 460-470MHz on UHF. That might be a better choice. I've had two of the GP-9NCs and can say they work great on GMRS. I still have one sitting in the rafters of my garage. 800 would still be a crap shoot on these.

I just want it to recieve. most of the frequencies are 155 range and 453-478. So would this work for that? I had a comet GP15 which picked up the 800 bank pretty well, although it was not tuned for that. Any recommendations? I have a discone now which i want to replace and do not want a wide band like that because the gain is so small

 

[rangers38]

The antenna will certainly receive there but if it advertises 6.9dB gain on VHF and 9dB gain on UHF within the amateur bands (both extreme lies) then expect much less, maybe half or less when you push the antenna very far from its design frequency.

There are commercial versions of some antennas like the Comet GP6-NC and GP-9NC which are factory tuned for 153-157MHz on VHF and 460-470MHz on UHF. That might be a better choice. I've had two of the GP-9NCs and can say they work great on GMRS. I still have one sitting in the rafters of my garage. 800 would still be a crap shoot on these.

OK-Understood. If I were to replace my Diamond130JN with either of the Comet versions , would my reception increase significantly over the discone? The discone pretty much has very little gain. Even if the dB gain was not as advertised because the frequencies are slightly off the specs, I would think it's better than the discone??

 

[prcguy]

Within the advertised frequency range of a Comet GP-9NC, your reception would go through the roof compared to a Discone. It would be a night and day type of change. I use an amateur version GP-9N all day long on 2m/70CM and when I switch to a Discone at a similar height some distant signals just go away and strong signals go down significantly. A GP-9 is almost 18ft tall, its a lot of antenna.

OK-Understood. If I were to replace my Diamond130JN with either of the Comet versions , would my reception increase significantly over the discone? The discone pretty much has very little gain. Even if the dB gain was not as advertised because the frequencies are slightly off the specs, I would think it's better than the discone??

 

[Ubbe]

I use a Diamond X510 and it pretty much beat any 1/4 wave GP that I have made for different frequency bands, even at 1090MHz.
I can only verify with the local cellphone tower that use 850-950MHz as we have no commercial radio above 470MHz and it receives a good signal in that band as well but I don't have any proper 850MHz antenna to compare to.

On VHF air it works better than a 1/4 wave GP, which is equal or better than a discone, and are equal and sometimes better than a 5/8 wave GP antenna tuned for VHF air. The Diamond antennas are not so expensive and you can probably sell it without too much loss to a radio amateur if it doesn't work out.

/Ubbe

 

[rangers38]

Within the advertised frequency range of a Comet GP-9NC, your reception would go through the roof compared to a Discone. It would be a night and day type of change. I use an amateur version GP-9N all day long on 2m/70CM and when I switch to a Discone at a similar height some distant signals just go away and strong signals go down significantly. A GP-9 is almost 18ft tall, its a lot of antenna.

I would probably go with the GP6-NC as it's 10Foot. I don't want to have multiple antenna's , so I am not sure how to address the 800 Mhz. If I did go with multiples what would the recommendation be. Also I have my antenna outside now. If I were to move it into the attic, would the reception really diminish?

 

[rangers38]

I use a Diamond X510 and it pretty much beat any 1/4 wave GP that I have made for different frequency bands, even at 1090MHz.
I can only verify with the local cellphone tower that use 850-950MHz as we have no commercial radio above 470MHz and it receives a good signal in that band as well but I don't have any proper 850MHz antenna to compare to.

On VHF air it works better than a 1/4 wave GP, which is equal or better than a discone, and are equal and sometimes better than a 5/8 wave GP antenna tuned for VHF air. The Diamond antennas are not so expensive and you can probably sell it without too much loss to a radio amateur if it doesn't work out.

/Ubbe

My requirements would be to monitor public safety channels for police/fire/ems. The following spread of channels 155-158mhz, 453-460mhz,
& 856-860Mhz.
So basically looking for the best option here

 

[prcguy]

If I wanted really great reception across your specific frequency ranges and didn't need any VHF air, T band, etc, I would consider a GP-6NC or GP-9NC then a surplus 700/800MHz gain type omni and diplex them together. I occasionally see big commercial 800 antennas sold off cheap at local ham swap meets and sometimes Ebay.

I have all that available here with separate commercial VHF-lo/VHF-hi/VHF-UHF aircraft/UHF/900 repeater type antennas and lots of diplexers, but I live on a hill and use a pair of amplified and filtered Discones for most monitoring. Most of my big commercial antennas just sit on the tower and corrode.

Going to the attic will reduce reception some at the least and depending on roofing/siding materials and other things, reception could be drastically reduced.

I would probably go with the GP6-NC as it's 10Foot. I don't want to have multiple antenna's , so I am not sure how to address the 800 Mhz. If I did go with multiples what would the recommendation be. Also I have my antenna outside now. If I were to move it into the attic, would the reception really diminish?

 

[cmdrwill]

Attic antenna.

 

[rangers38]

If I wanted really great reception across your specific frequency ranges and didn't need any VHF air, T band, etc, I would consider a GP-6NC or GP-9NC then a surplus 700/800MHz gain type omni and diplex them together. I occasionally see big commercial 800 antennas sold off cheap at local ham swap meets and sometimes Ebay.

I have all that available here with separate commercial VHF-lo/VHF-hi/VHF-UHF aircraft/UHF/900 repeater type antennas and lots of diplexers, but I live on a hill and use a pair of amplified and filtered Discones for most monitoring. Most of my big commercial antennas just sit on the tower and corrode.

Going to the attic will reduce reception some at the least and depending on roofing/siding materials and other things, reception could be drastically reduced.

So, If I purchased this antenna in conjuction with the other and ran additional LMR 400 and used a diplexer, this would be my best bet to cover the frequencies I am trying to monitor??

LAIRD 806-866MHz 3 dB gain fiberglass omnidirectional, 150 watt power Direct N

 

[rangers38]

cmdrwill

How does that antenna work on the 800 MHZ inside the attic?

 

[cmdrwill]

@cmdrwill
How does that antenna work on the 800 MHZ inside the attic?

That one is scaled for two meter, 146 mHz with 18 inch radials. You could scale that configuration for the 800 band using a 800 mHz NMO mount antenna. Easy to get parts, the plate is a electrical box cover with the 3/4 in hole knock out for the NMO mount.