RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > Topic Specific Forums > Antennas and Associated Hardware > Scanner / Receiver Antennas

Scanner / Receiver Antennas For discussion of any type of receiving antenna used by a scanner or receiver base, mobile or handheld.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 11-24-2012, 7:32 AM
ScanPEI's Avatar
Member
  Shack Photos
Shack photos
Audio Feed Provider
Audio Feed Provider
 
Join Date: Feb 2008
Location: PEI, Canada
Posts: 299
Default Need Help With Antenna

I have used a UHF/VHF TV antenna for years with excellent results for my local 800mhz trunk system. But last year I moved into a mini home (aka: trailer) that is surrounded by metal eaves, trimming and trees and my excellent working antenna is not so excellent anymore. I do get some reception but it comes and goes. I've tried it on the roof with no improvements. I then thought of throwing the antenna up in a tree but after doing some reading, thought it would only lead to more problems. Even walking around the yard with the rubber duck antenna signal is hit and miss. Anyone have any suggestions as to what I could do. Could a signal amplifier make an improvement? I rent, so attaching anything to the house is not likely. Scanner is a Pro-97 scanning the 800mhz range.

Input much appreciated!
__________________
Daniel Deziel
ScanPEI Owner
Prince Edward Island's Radio Scanning Community
ScanPEI.net | Facebook | Twitter
Reply With Quote
Sponsored links
  #2 (permalink)  
Old 11-24-2012, 7:39 AM
gewecke's Avatar
Member
  Premium Subscriber
Premium Subscriber
Amateur Radio Operator
Amateur Radio
 
Join Date: Jan 2006
Location: Illinois
Posts: 5,803
Thumbs up

Have you tried rotating your antenna towards your desired signals? I'm assuming your tv antenna is directional right?
You could also try ground mounting it to a mast so it would be away from obstructions?

73,
n9zas
__________________
"Whatever doesn't kill you...will make you stronger"!
Reply With Quote
  #3 (permalink)  
Old 11-24-2012, 8:09 AM
rfradioconsult's Avatar
Member
   
Join Date: Dec 2004
Location: Tulsa
Posts: 1,117
Default

If you haven't tried turn your antenna so the elements are vertical not horizontally as TV antennas are normally installed. LMR uses vertical polarization, OTA TV is normally horizontal.
Reply With Quote
  #4 (permalink)  
Old 11-24-2012, 8:13 AM
Dewey's Avatar
Member
  Premium Subscriber
Premium Subscriber
 
Join Date: Dec 2002
Posts: 957
Default

Just a personal opinion, but it you were happy using a TV antenna, Radio Shack's 20-176 (affectionately known to many of us here as "Sputnik") may please you. The 20-176 is a small very low cost (shows $29.99 on line right now, so they've raised the price a little) antenna that can perform up there with the big boys. Due to its size, and low number of elements, just 3 ground radials, it will fit in a lot of tight places. Again, just a personal opinion, your mileage may vary.
Reply With Quote
  #5 (permalink)  
Old 11-24-2012, 4:09 PM
Member
   
Join Date: Mar 2009
Location: United Kingdom
Posts: 280
Default

Quote:
Originally Posted by ScanPEI View Post
I have used a UHF/VHF TV antenna for years with excellent results for my local 800mhz trunk system. But last year I moved into a mini home (aka: trailer) that is surrounded by metal eaves, trimming and trees and my excellent working antenna is not so excellent anymore. I do get some reception but it comes and goes. I've tried it on the roof with no improvements. I then thought of throwing the antenna up in a tree but after doing some reading, thought it would only lead to more problems. Even walking around the yard with the rubber duck antenna signal is hit and miss. Anyone have any suggestions as to what I could do. Could a signal amplifier make an improvement? I rent, so attaching anything to the house is not likely. Scanner is a Pro-97 scanning the 800mhz range.

Input much appreciated!
Nope a signal or pre amp is not going to solve this for you - unless you also add a filter with a nice steep roll off on both bandwidth edges.

Try resolve this problem trying out the tricks other members have mentioned.

The problem with a pre-amp is that while its going to boost the signal it's also going to boost all the trash around the P25 signal, and unless you can measure (or make a good guestimation) regards your existing CNR level, there's a fair old chance that no matter how much you boost the signal, you are not going to realise any improvement to the Signal/Carrier to Noise Ratio.

Get an antenna setup so that you can at least realise constant or consistant demodulation - no matter how quiet or low the demodulated audio is - then add a preamp, but not before.
Reply With Quote
Sponsored links
  #6 (permalink)  
Old 11-29-2012, 5:31 PM
Member
   
Join Date: Dec 2011
Posts: 51
Default

Throw it up in a tree or at least tie a string with a weight, throw it up a tree , then pull your ant up there. Don't believe everything you read, in your case, height is the important thing
Let me know how it works out
Reply With Quote
  #7 (permalink)  
Old 11-30-2012, 1:18 PM
Member
   
Join Date: Mar 2009
Location: United Kingdom
Posts: 280
Default

Quote:
Originally Posted by papillon View Post
Throw it up in a tree or at least tie a string with a weight, throw it up a tree , then pull your ant up there. Don't believe everything you read, in your case, height is the important thing
Let me know how it works out
Don't laugh - a 3m or 4m (cubic volume of course) balloon filled with helium is another great way of raising an antenna!

Using the coax both to carry the signal back to ground level as well as to tether the balloon to whatever height you want to tether it at. To secure the coax at ground level obviously you don't tie it into a knot - use a length of cheap braided type rope of suitable diameter: compress the braiding in the axial direction (so that the braiding expands), slip the coax & connector through this section of the chord/rope, and then stretch the rope out again so that it compresses in a radial fashion around the coax.

6" to 8" of "glove fitting" around the coax will provide more than sufficient friction & resistance to withstand several times the (-)gravity force been exerted upwards by the helium and will do no damage to your coax.

If I am not mistaken in the USA you can freely & without any regulation of any sort raise a helium balloon to 60m or 198' above surrounding ground level (using 3.3' x p/meter conversion rate).

Obviously impractical if it's a Yagi or someother directional type antena, but with an omni-directional raised to this height you are going to be enjoying Fresnel Zone clearance thats likely to realize for you pretty much as much extra dB/gain as your typical small off-the-shelf Yagi would in any case.

Last edited by benbenrf; 11-30-2012 at 1:22 PM..
Reply With Quote
  #8 (permalink)  
Old 11-30-2012, 2:48 PM
Member
  Premium Subscriber
Premium Subscriber
Amateur Radio Operator
Amateur Radio
 
Join Date: Jun 2007
Location: Grandview, TX
Posts: 91
Default

I noticed that you "moved" from point a to point B. Details of "Point B" are not included: Terrrain, Mountains or hills, distance to the trunking site you wish to monitor. ALL are important to know. A directional antenna is absolutely ineffective if you live in a hole. Give us some more info, please.
Reply With Quote
  #9 (permalink)  
Old 10-24-2013, 9:36 PM
ScanPEI's Avatar
Member
  Shack Photos
Shack photos
Audio Feed Provider
Audio Feed Provider
 
Join Date: Feb 2008
Location: PEI, Canada
Posts: 299
Default

Quote:
Originally Posted by ab5r View Post
I noticed that you "moved" from point a to point B. Details of "Point B" are not included: Terrrain, Mountains or hills, distance to the trunking site you wish to monitor. ALL are important to know. A directional antenna is absolutely ineffective if you live in a hole. Give us some more info, please.
Place I lived before was a very small town, 2 story house. I am closer to the trunking site now, than I was before. Land is flat in both locations. Location A I hung the TV antenna from the ceiling horizontally. Now I tried every different direction with no results. I believe the trees are the biggest issue.
__________________
Daniel Deziel
ScanPEI Owner
Prince Edward Island's Radio Scanning Community
ScanPEI.net | Facebook | Twitter
Reply With Quote
Sponsored links
  #10 (permalink)  
Old 10-31-2013, 4:01 PM
ScanPEI's Avatar
Member
  Shack Photos
Shack photos
Audio Feed Provider
Audio Feed Provider
 
Join Date: Feb 2008
Location: PEI, Canada
Posts: 299
Default

I know this topic is old, but still have the same issue. Never got a new antenna as of yet.

I'm wondering. I have a small wide band magmount mobile antenna (KS3) that works fair when on my roof. If I stuck that thing 25-30' up on a pole and buy an 25' bnc male to female extension cable ($30 shipping included), could that possibly improve reception? Wouldn't hurt to try I guess. Would be better than buying a $100-$200 antenna and not get any new results. Will keep you updated!
__________________
Daniel Deziel
ScanPEI Owner
Prince Edward Island's Radio Scanning Community
ScanPEI.net | Facebook | Twitter
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 10:08 PM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2011 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions