Digital Scanner + Attic Antenna = ??

Status
Not open for further replies.

wx4svr

Member
Joined
Apr 12, 2008
Messages
163
First off, Hi. :lol: I usually hang out in the KY forum because that's where I am. Anyways.. here's the dilemma I am in.

I live in a neighborhood in eastern Louisville that will not allow any type of mast to be erected. (or anything be constructed without permission for that matter) I have spoken to the guys at Scanner Master regarding putting an antenna in my attic, but I still have a few questions. First, I will show you what they sent me...

WBV-40 Discone Base Antenna
WBD-40 Discone Base Antenna

WBV-60 Wideband Base Antenna
WBV-60 Wideband Base Antenna

DD1300 Double Discone Base Antenna
DD1300 Double Discone Base Antenna

Ferret 8 Band Base Antenna
Ferret 8 Band Base Antenna

Coax would be needed for the antennas above:
> LMR-400 Coax Cable, 25’ with N Male & BNC Male
> LMR-400 Coax Cable, 50’ with N Male & BNC Male
> LMR-400 Coax Cable, 75’ with N Male & BNC Male
> LMR-400 Coax Cable, 100’ with N Male & BNC Male

Indoor Base Antennas
Not able to put a antenna on the outside of your home check out this one…
> WAN-97A Active Nomad Base Antenna (powered with 4 AA batteries)
I have tested this antenna and it works very well indoors!

The antenna will likely be hooked up to a GRE base model digital scanner (PSR-600) and will be working mostly with the new MetroSafe system about to me put into place by Metro Louisville. It's a P25 system. I currently use a PRO-2051 and a antenna similar to this one by Radio Shack. It is currently on top of a desk next to a window and it works "okay"... but I know once the switch to digital occurs, I will need more.

Now... my questions.

  1. The antenna will need to be able to pick up signals from about 30 miles away. Which would you suggest? (Remember.. it's going in an attic)
  2. How would you mount an antenna in an attic?
  3. Should I worry about interference from the roof or shingles? (I've never put an antenna in the roof before)
  4. Could I mount the antenna in the horizontal orientation instead of vertical? ( --- instead of | )

Thanks so much.
Cody, wx4svr
 

fineshot1

Member
Joined
Sep 17, 2004
Messages
2,532
Location
NJ USA (Republic of NJ)
1. The antenna will need to be able to pick up signals from about 30 miles away. Which would you suggest? (Remember.. it's going in an attic)

This is not always possible due to a variety of reasons like the terrain in between your antenna
and the transmitters power output and many other reasons.

2. How would you mount an antenna in an attic?

That would depend on the antenna chosen and the layout and design of your attic space - many
attic installs are a make it up as you go thing.

3. Should I worry about interference from the roof or shingles? (I've never put an antenna in the roof before)

There may be some attenuation due to being mounted inside due to the house sideing and such
but it should not be too bad.

4. Could I mount the antenna in the horizontal orientation instead of vertical? ( --- instead of | )

Definately DO NOT mount it horizontally as almost all of the public safety antenna's are mounted virticaly.
 

crevatis

Member
Joined
Dec 29, 2004
Messages
73
Location
Kenosha, WI
I have a similar situation using a BC396 and a discone in the attic. The farthest P25 I have reached with it is 25 miles out at 100 watts VHF from a 55m tower. It comes in very clearly though. My discone is simply standing on its cone and obviously vertical.
 

ka3jjz

Wiki Admin Emeritus
Joined
Jul 22, 2002
Messages
25,361
Location
Bowie, Md.
Cody something else you will want to do - I've done as much in my own attic - walk around with your handheld and see if you can mark out some sweet spots where the signals you want to hear are coming through well. Every attic has a few - but it does take some hunting to find them. Use the worst HT antenna you have - don't use a gain duckie that would potentially slew the results. 73 Mike
 

nanZor

Active Member
Joined
May 28, 2009
Messages
2,807
Cody something else you will want to do - I've done as much in my own attic - walk around with your handheld and see if you can mark out some sweet spots where the signals you want to hear are coming through well. Every attic has a few - but it does take some hunting to find them. Use the worst HT antenna you have - don't use a gain duckie that would potentially slew the results. 73 Mike

That is EXCELLENT advice! Use the attenuator as well to help find the hot spots if the system can be heard at all with the attenuator on temporarily.

Depending on what is up there, the attic can be a pretty hostile place for noise. Be sure to run the feedline away from other conduits / cables, and if you have to cross them try to do so at a 90 degree angle to help avoid coupling to the feedline.

I also recommend using type-43 ferrite chokes, at least 4 of them, near the feedpoint. RS 273-105 snap-ons come to mind if they will fit your cable. Type-43's can be found elsewhere for a bit less $$.

A recent expedition to a friend's attic revealed that when using beams, run the feedline directly past the back of the reflector, rather than hanging straight down from the driven element. In the attic you have this luxury of feedline routing..

Be aware of safety issues - other than not putting your feet through the ceiling, take care not to put a rusty nail into your head sticking down from the roof !! Good lighting is essential - those headband lights come in very handy.
 

wx4svr

Member
Joined
Apr 12, 2008
Messages
163
Thanks everyone! I''m taking all this into advisement. I'm still not sure what I am going to get yet. (as I still have to get the new Digital Scanner.. lol) I'll take a pic of it when it is done and post it. It's a brand new house in a really nice neighborhood so I think it should be relatively easy.
 

dwlyons

Member
Joined
Jun 1, 2009
Messages
188
Location
Hedgesville, WV
I have 3 scanner antennas mounted in my attic, simply for aesthetic purposes. They are:

1. Skyscan V1300 Desktop discone antenna
2. Diamond D-130J discone antenna
(Both yeild P-25 reception in excess of 40 miles & conventional reception in excess of 80 miles)
3. A homemade ground plane style using an old tri-band fiberglass scanner antenna (use for both VHF & UHF aircraft band reception)

Getting ready to add an additional Diamond D-130J to my array for usage with a radarbox.

I made mounts using 1-1/4" schd 40 PVC pipe which provide stability for spanning the trusses. Cheap, easy and quick to make. I needed the following:

1 - 5' piece of 1-1/4" PVC
5 - 1-1/4" 90 degree bends
1 - 1-1/4" PVC cap
1 - sm can of PVC glue

There is a decent discone on Ebay, Item # 280430733360 for approx $35.00.
 

wx4svr

Member
Joined
Apr 12, 2008
Messages
163
I have 3 scanner antennas mounted in my attic, simply for aesthetic purposes. They are:

1. Skyscan V1300 Desktop discone antenna
2. Diamond D-130J discone antenna
(Both yeild P-25 reception in excess of 40 miles & conventional reception in excess of 80 miles)
3. A homemade ground plane style using an old tri-band fiberglass scanner antenna (use for both VHF & UHF aircraft band reception)

Getting ready to add an additional Diamond D-130J to my array for usage with a radarbox.

I made mounts using 1-1/4" schd 40 PVC pipe which provide stability for spanning the trusses. Cheap, easy and quick to make. I needed the following:

1 - 5' piece of 1-1/4" PVC
5 - 1-1/4" 90 degree bends
1 - 1-1/4" PVC cap
1 - sm can of PVC glue

There is a decent discone on Ebay, Item # 280430733360 for approx $35.00.

Thanks. I'm going to look into these and see if I can get either of these. The more coverage, the better imo.
 

iMONITOR

Silent Key
Premium Subscriber
Joined
Sep 20, 2006
Messages
11,156
Location
S.E. Michigan
Now... my questions.

  1. The antenna will need to be able to pick up signals from about 30 miles away. Which would you suggest? (Remember.. it's going in an attic)
  2. How would you mount an antenna in an attic?
  3. Should I worry about interference from the roof or shingles? (I've never put an antenna in the roof before)
  4. Could I mount the antenna in the horizontal orientation instead of vertical? ( --- instead of | )
Thanks so much.
Cody, wx4svr


You didn't say what band/frequency range you plan to monitor. If it's the 800MHz band, none of the antennas in your list would be a good choice.
 

iMONITOR

Silent Key
Premium Subscriber
Joined
Sep 20, 2006
Messages
11,156
Location
S.E. Michigan
It's the new MetroSafe P25 system. I'm new at this scanner stuff, so please excuse me. Here is what we know...
Louisville MetroSafe Info

30 miles is going to be a stretch for an attic mounted antenna. Is your home one, or two story? You will definitely need a Yagi high-gain antenna. Mounting will be simple, as they are not very big. Some people just hang them by some mono filament fishing line, or clamp a small mast to one of the wood 2x4's in the attic.

Something like this is what you want:
http://cgi.ebay.com/Mini-Yagi-800-9...wItemQQptZPDA_Accessories?hash=item518e4ce2ef
 
Last edited:

mrkelso

Member
Joined
Dec 4, 2008
Messages
1,530
Location
NNJ
28-541171-2.jpg


Hung one of these actives from ScannerMaster in my attic today and i am now able to hear 482.2312 as well as several other freqs in New York that the Discone just didn't want any part of. Go figure.
 

ka3jjz

Wiki Admin Emeritus
Joined
Jul 22, 2002
Messages
25,361
Location
Bowie, Md.
Nothing to 'figure' here at all, really. This is a short loaded whip of some kind with a wideband preamp. The discone has very little, if any, gain at all (indeed, I've found descriptions that describe it as a 0db gain antenna- if you consider that it's at zero, where a lot of little duckies are in the minus range, mathematically that's gain...) although it's also widebanded.

One thing to watch for - in an urban area, this could easily overload a handheld or lower end base scanner. I wouldn't hesitate with a R7000 or similar, but an old BC898 might be pushing it a bit.

73 Mike
 

mrkelso

Member
Joined
Dec 4, 2008
Messages
1,530
Location
NNJ
So far i do not detect any overloading. Right now i am using it on my Shack Pro-160. I just programmed in the area airports and i can hear them good now where as before i was getting voice buried in static.

A Happy Scannist...
 

jafarm66

Member
Joined
Mar 30, 2005
Messages
56
Location
Broward County Florida
I just ordered the following antenna. I've tried several different ones in my area of South Florida. Since I live in a condo I can't do an outdoor antenna. I tried mounting an Outdoor antenna inside and it wasn't as good as a band specific rubber duck. So far the best reception I've gotten is with the Austin Condor 12" antenna. I have 2 of them one on my 396XT and one on my GRE PSR-500. Now I will be using the Watson antenna below, it will be hanging from the ceiling and plugged into the 396XT for Palm Beach County Reception, I live in Broward which I receive fine.

http://www.scannermaster.com/v/vspfiles/photos/28-541171-2.jpg
 

benbenrf

Member
Joined
Mar 27, 2009
Messages
287
Location
United Kingdom
First off, Hi. :lol: I usually hang out in the KY forum because that's where I am. Anyways.. here's the dilemma I am in.

I live in a neighborhood in eastern Louisville that will not allow any type of mast to be erected. (or anything be constructed without permission for that matter) I have spoken to the guys at Scanner Master regarding putting an antenna in my attic, but I still have a few questions. First, I will show you what they sent me...



The antenna will likely be hooked up to a GRE base model digital scanner (PSR-600) and will be working mostly with the new MetroSafe system about to me put into place by Metro Louisville. It's a P25 system. I currently use a PRO-2051 and a antenna similar to this one by Radio Shack. It is currently on top of a desk next to a window and it works "okay"... but I know once the switch to digital occurs, I will need more.

Now... my questions.

  1. The antenna will need to be able to pick up signals from about 30 miles away. Which would you suggest? (Remember.. it's going in an attic)
  2. How would you mount an antenna in an attic?
  3. Should I worry about interference from the roof or shingles? (I've never put an antenna in the roof before)
  4. Could I mount the antenna in the horizontal orientation instead of vertical? ( --- instead of | )

Thanks so much.
Cody, wx4svr

1. Pick up signals from 30miles?
The only way you are going to be able to work this out is to calculate path loss for a given signal over the 30mile distance (do you know how to do that??), add that that to the gain your antenna can provide for that particular frequency (and antennaa gain changes as frequency changes), and now compare it with the manufacturers sensitivity figures for your receiver at different bandwidths for FM & AM (which will all be in the specifications section of the manual that came with your receiver/scanner).

If the figure you get is less than the sensitivity figures given (and note: receiver senstivity figures change for different bandwidths at different freq's and modulation types), unless you add a preamp, no you'll not pick the signal up, if its above the min figure then you should be okay - depending on your SNR (signal to noise ratio).

2. How to mount it in the attic?
Ask the manufacturer - they generally know best.

3. Inteference from roof shingles?
Interference as in attentuation of incoming signal - yes - potentially big time (more so the higher the frequency).

4. Horizontal or Vertical position?
Vertical - without VHF/UHF transmissions are vertically polarised

Your roof shingles and rafters are goinjg to do you no favours - and set the attena up as far as poss from any copper/steel water storage tank or boiler you may have in your attic.

Whats the rule regards outside/roof/eve mounted TV antenna's in your area? Surely they are allowed.
 

jafarm66

Member
Joined
Mar 30, 2005
Messages
56
Location
Broward County Florida
Watson WAN 97A Active Antenna

Just got the Watson WAN-97A Active Antenna hanging from my ceiling via a hook and it has dramatically improved my listening experience from my 1st floor condo.
 

Ramathorne

Member
Joined
Jan 24, 2011
Messages
206
Location
Nova Scotia
You didn't say what band/frequency range you plan to monitor. If it's the 800MHz band, none of the antennas in your list would be a good choice.

I was looking at the Antennacraft ST2, WBV-60, and SA7000
Looking to improve range, specifically 800 range
Any of those any good?

What would be recommended for a more rural area (non discone due to weather extremes)
 
Status
Not open for further replies.
Top