800mhz range vs VHF?

Status
Not open for further replies.

Sparky_ND

Member
Joined
Jun 26, 2021
Messages
39
Location
Napoleon, ND
The ND SIRN system is spreading into my area within a year, so I'm curious as to how distant of towers I'm likely to receive as compared to the current vhf towers. Right now I can generally pick up towers out to about 70 miles on the average day, 150+ when we get the crazy tropo going.
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
It'll depend entirely on how the system is designed.

When the design the system, they'll build it out to a certain percentage of coverage for mobile radios, or portable radios. Depends on what the needs are. If they are building it as a replacement for an existing VHF system, you can probably expect coverage to be similar to what they have now, maybe a bit better.

If it's built out for 95% (or more) of mobile coverage, you'll probably do OK with a regular scanner and an outdoor antenna.
If they build it out for 95% (or more) of portable radio coverage, you'll probably do OK with a hand held scanner with the stock antenna.

Really depends on what the design is for. Since building the sites is expensive, it's designed very carefully. They design based on the coverage they want for their intended use. Providing coverage to scanner listeners isn't one of the goals, but you'll probably benefit if they are building it out for portable radio coverage in your area.

As always, a good external antenna will greatly improve performance.
 

Sparky_ND

Member
Joined
Jun 26, 2021
Messages
39
Location
Napoleon, ND
After doing some research, it seams there is already a lot of 800mhz towers in the 50-70 mile range from my location, but nothing closer. No control channels, and never caught any activity from hours of sweeping the band. Just the local cell towers, so I'm not expecting to hear as much action as I've been used to.800.png
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
If you are using the Tram 1410 discone shown in your signature line, that's not doing you any favors on 800MHz.
The type and length of coaxial cable can be losing a lot of your signal, too.
 

Sparky_ND

Member
Joined
Jun 26, 2021
Messages
39
Location
Napoleon, ND
Yes, thats using the discone and 15ft of rg58 24ft off the ground. I guess I might have to consider a specific antenna for the 800mhz band, I have a few parts laying around might have to do some expirimenting.
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
That would be a good idea.

You could also up your coaxial cable game a bit. 15 feet of RG-58 isn't bad, it's what you find on most mobile installations. But you can get some more signal to your radio by using a higher grade cable. Even RG-6 would get you another 1dB.
But discone antennas are not great. Their usefulness is that they are really broad banded and make good scanner antennas. But they have zero gain, even less on the higher frequencies, and will perform poorly compared to a purpose built 800MHz antenna.
 

Sparky_ND

Member
Joined
Jun 26, 2021
Messages
39
Location
Napoleon, ND
The discone actually tested better than the 800mhz magnet mount by 6db on the cell signals between 700-900, with a whole 5 ft height difference. I envision a couple homebrew yagi's in my future, theres already a couple 2.4ghz and a dual band on the roof.
 

west-pac

Member
Joined
Nov 13, 2004
Messages
1,564
After looking at the ND SIRN listing, it looks like only one site was actually received, and indicates that it's online. The rest of the sites listed appear to just be copied from an FCC license, or some other source, but not actually received or heard as being online. In those site notes, even though a site number has already been assigned by the RRDB Admin who added all of that information, the site notes say "site number unknown". That SIRN DB listing looks like a bunch of inaccurate BS, especially since there are no CC's or ACC's listed.... that means those sites were never actually received by anyone.


Smh. I can't believe some RRDB Admin added all of that license information from paper, without anything actually being received or submitted to be added to the DB. That is not the correct way that that is done on RR. Everything listed on RR is supposed to be verified online and actuate before being added to RR website. From looking at the license information some of these sites are going to be simulcast as well, such as the ONE site that has a CC, and at least 3 out of the 5 sites listed for Williams county.
 

Sparky_ND

Member
Joined
Jun 26, 2021
Messages
39
Location
Napoleon, ND
After some research, the 1411 is supposed to have pretty even gain from 100-500, and 700-900, the rest of the frequencies are rather weak. Judging by reception of the cell towers I might get decent coverage, just not like what you get out of vhf, hence more towers are being added.
 

mmckenna

I ♥ Ø
Joined
Jul 27, 2005
Messages
23,615
Location
Hiding in a coffee shop.
After some research, the 1411 is supposed to have pretty even gain from 100-500, and 700-900, the rest of the frequencies are rather weak. Judging by reception of the cell towers I might get decent coverage, just not like what you get out of vhf, hence more towers are being added.

Don't forget your coax. The higher the frequency, the more pronounced the losses are in coaxial cable.
 
Status
Not open for further replies.
Top