Worse reception since hooking up my outside antenna

[Pape]

Got a little the same, while the discone and the coax alone did put the commercial fm band on overdrive it did not affect much what I was listening to. The fm filter became a requirement when adding lna and splitter.

There is also a certain learning curve in gain adjustment, gone are the days where you just put the gain at max.

 

[emsflyer84]

Jumping in on this feed just to post my own experience with outside antenna/. I always had a roof top antenna but when I upgraded my feed line, connectors, etc, my reception got worse. Turns out there are some very strong pager transmitters somewhere close that are overloading my scanner now so more distant signals are getting blocked out. I'm having a custom filter made by PAR Electronics to try and deal specifically with the pager interference.

 

[dave3825]

Jumping in on this feed just to post my own experience with outside antenna/

I always had a roof top antenna but when I upgraded my feed line, connectors, etc, my reception got worse. Turns out there are some very strong pager transmitters somewhere close that are overloading my scanner

Just curious, what feed line were you using, and what did you upgrade to?

 

[emsflyer84]

Just curious, what feed line were you using, and what did you upgrade to?

So I was using standard household cable coax, not sure what it's called. On top of that I had it connected in my basement to my entire household coax network that runs all throughout the walls of the house. I did this so I could plug my scanner into the cable jack in the wall under my desk in my office. It actually worked well! But I noticed there were a few frequencies that would sometimes not come in well. Figured I'd upgrade my feed line to LMR400, and only use a 35' run down the side of my house right to the back of the scanner on my desk using a window jumper. Shortened my total run by probably 100' or more. And reception got worse. After ruling out interference from something in my own house, I was able to determine my antenna was picking something up that was interfering. After some suggestions from people here on the forum, I found two VHF frequencies absolutely blasting a digital sounding pager frequency, probably overloading the scanner just enough to mess with the more distant stuff I'm trying to pick up. My old crappy feed line was probably attenuating the pager stuff for me. I'm not 100% sure this is my issue, but I'm 95%. We'll see when I get my filter.

 

[dave3825]

When I bought my home there was rg 6 coming in from the cable co to the modem and router but all the wire in the walls was rg 58. All been replaced.

Possible your old feed line was antunating but you said reception was good. I take it you have gone over every connection on the new feed line?

 

[emsflyer84]

When I bought my home there was rg 6 coming in from the cable co to the modem and router but all the wire in the walls was rg 58. All been replaced.

Possible your old feed line was antunating but you said reception was good. I take it you have gone over every connection on the new feed line?

Yes I have, I do have a multi-coupler connecting two scanners to the same antenna, but I've tried connecting a scanner directly to the end of the feed line eliminating the window jumper an coupler, no improvement. I did a test where I locked my scanner on the distant frequency I'm trying to receive and opened the squelch all the way. I got 3+ bars on the signal meter, telling me the antenna was picking something up but I wasn't hearing anything but static. When I turned the volume up I could hear a faint digital sounding pager noise in the static. When I disconnected my antenna from the back of the scanner, the pager noise and signal bars went away. This is what lead me on the path of thinking my antenna is picking something up.

 

[emsflyer84]

When I bought my home there was rg 6 coming in from the cable co to the modem and router but all the wire in the walls was rg 58. All been replaced.

Possible your old feed line was antunating but you said reception was good. I take it you have gone over every connection on the new feed line?

Also, just to clarify, reception is still generally good, it's really just one or two more distant VHF conventional digital frequencies I'm now having trouble with.

 

[Pape]

Alternatively you buy a variable attenutor or solit set and add attenuation to the line and validate.
For me it was FM radio I was able to ear it way up in the spectrum where it did not belong

 

[emsflyer84]

Alternatively you buy a variable attenutor or solit set and add attenuation to the line and validate.
For me it was FM radio I was able to ear it way up in the spectrum where it did not belong

This is an interesting idea, I’ll look into it. I have an FM filter I tried already and it didn’t help. Another interesting note…. I took my handheld up in the roof and picked up the frequency I’m NOT getting with the roof antenna and base scanner….

 

[GadgetGeek]

I'm having a custom filter made by PAR Electronics to try and deal specifically with the pager interference.

I use a PAR notch filter too for pager interference in the 152 MHz range. Best $30 spent.

 

[emsflyer84]

I use a PAR notch filter too for pager interference in the 152 MHz range. Best $30 spent.

Thanks, I hope it helps my situation, I'm at a bit of a loss otherwise.... I can pick up stuff sitting in my car in the driveway that my roof antenna is having trouble with. I think my mobile antenna isn't picking up the interference to such a strong degree....

 

[emsflyer84]

Good afternoon guys, just a quick update on my reception issues. Randomly two days ago the frequency I've been missing started coming in loud and clean in the evening, around 5:30pm. Was fine all evening. I did the interference test on my scanner, manually tuned to the frequency in question and opened the squelch all the way. Only two signal bars on the screen as opposed to 5 that I had been getting (less interference signal?) The next day (yesterday), I couldn't hear them again. Then, same thing, sometime in the evening they started coming in clear. Now today, I'm not picking them up again.

A couple thoughts. First, this leads me to believe that my interference issue isn't actually from the pagers in my area since I was still picking up the pagers on their frequencies just as strong as I was before, even when receiving well in the evenings. Second, maybe just a coincidence, but earlier the day this happened, the power company was doing utility work on some lines about 3 miles from my house, but almost line-of- site. Also, power company trucks have been driving all around my neighborhood the past couple days. I haven't seen them out in the area in months until now. All these things are making me lean more toward maybe power line noise causing my issues. I had similar experiences a few years ago when the lines around my house were being replaced. I'd get great reception sometimes, then terrible reception issues during the days they were working on the system. Finally once all the work was done, I had no more issues. I wonder if there is another utility project taking place in the area. At this point I'm just going to let it play out for a while. I have some hope because of the great reception I've had the past couple nights. We'll see what happens...

 

[ratboy]

I put together one of these for a friend last night.

Since it was here at work, I decided to have an little antenna showdown to see what works the best. It's a tough place for any receiver, there are hundreds of PCs and servers in this building, along with a ton of LAN cables.
With the antennas hooked to the back of my SDS200, or sitting on my desk:
The factory whip worked pretty well. There was the usual total deafness on VHF high, but trunked stuff was OK.
The big rubber duck that I use on my PSR-500 was better on VHF (WX was blasting in), trunked stuff was about equal.
The discone was awful. Everywhere. Seemed odd to me. I ended up picking it up, and when I got the base about 6 feet up, it was like turning on a huge preamp. Only problem, there is no way to get it up that high without the tallest vertical element hitting the ceiling, so I removed it, and lost a lot of the VHF signal strength, but everything from 440MHZ on up was still pretty great. I took it home with me to try on my steel PC case, and I was pretty impressed. My apartment is on the second floor, and with the factory whip, MSPCS stuff was pretty weak, but with the discone, it's about 3X better, and I actually heard locomotives on the NS Chicago line a few miles away, so I guess I'm either going to get or make one as a project. I have a magnet mount that has been sitting unused that will work fine as a heavy base sitting in a drawer, and a bunch of brass rods from a long ago project, so I'm halfway there on parts already.

 

[rpectol]

I put together one of these for a friend last night.

Since it was here at work, I decided to have an little antenna showdown to see what works the best. It's a tough place for any receiver, there are hundreds of PCs and servers in this building, along with a ton of LAN cables.
With the antennas hooked to the back of my SDS200, or sitting on my desk:
The factory whip worked pretty well. There was the usual total deafness on VHF high, but trunked stuff was OK.
The big rubber duck that I use on my PSR-500 was better on VHF (WX was blasting in), trunked stuff was about equal.
The discone was awful. Everywhere. Seemed odd to me. I ended up picking it up, and when I got the base about 6 feet up, it was like turning on a huge preamp. Only problem, there is no way to get it up that high without the tallest vertical element hitting the ceiling, so I removed it, and lost a lot of the VHF signal strength, but everything from 440MHZ on up was still pretty great. I took it home with me to try on my steel PC case, and I was pretty impressed. My apartment is on the second floor, and with the factory whip, MSPCS stuff was pretty weak, but with the discone, it's about 3X better, and I actually heard locomotives on the NS Chicago line a few miles away, so I guess I'm either going to get or make one as a project. I have a magnet mount that has been sitting unused that will work fine as a heavy base sitting in a drawer, and a bunch of brass rods from a long ago project, so I'm halfway there on parts already.

What antenna is that? Looks like a cross between a multi-band V/UHF and a discone (which is strange because a discone is already multi-band by nature). Just guessing it might provide a little extra gain than a typical discone on certain target bands. What's the model or manufacturer? Thanks.

 

[Ubbe]

It's a discone antenna from something like 400MHz and upwards. The antennas on top of it works as GP antennas but they are not isolated from the discone at higher frequencies, and they are also tuned to be working in the same band as the discone. Discone and top elements will be 1/4 wave out of phase with each other so are not an optimal solution.

I would suggest to remove all top elements and then listen to a weak station in the 400-500MHz band and also in the 700-900MHz band and then add one element at a time starting with the coiled one and the longest and note if anything happens to the signal levels.

Then listen to a weak station in VHF and start to remove elements and note what happens to the signal level.

Then use the elements that are of use for the frequency bands where you have stations you need to improve without sacrificing too much in other bands.

/Ubbe

 

[blkscorpion2]

this is what that looks like to me, i have one in my garage sitting on the desk does a good job picking up almost everything.

https://www.amazon.com/Taurus-Desktop-25-3000-Scanner-Antenna/dp/B0C9HZ4GZT

 

[Tekton2]

In my opinion, discones don't make for effective antennas when it comes to scanning. I've found that a specifically tuned 800MHz antenna actually performs better across all frequencies compared to a wideband scanner antenna. I believe it has due with the quality of the materials of the higher end antenna, connectors, coax, etc..

 

[Ubbe]

I believe it has due with the quality of the materials of the higher end antenna, connectors, coax, etc..

It has to do with the lowest designed frequency of the discone. It's usually only working good over 5 octaves, like 100-500MHz. Outside of that band the direction pattern makes it worse than most other antennas as it has lost the direction pattern to the horizon.

/Ubbe

 

[TwoKings]

I put together one of these for a friend last night.

Since it was here at work, I decided to have an little antenna showdown to see what works the best. It's a tough place for any receiver, there are hundreds of PCs and servers in this building, along with a ton of LAN cables.
With the antennas hooked to the back of my SDS200, or sitting on my desk:
The factory whip worked pretty well. There was the usual total deafness on VHF high, but trunked stuff was OK.
The big rubber duck that I use on my PSR-500 was better on VHF (WX was blasting in), trunked stuff was about equal.
The discone was awful. Everywhere. Seemed odd to me. I ended up picking it up, and when I got the base about 6 feet up, it was like turning on a huge preamp. Only problem, there is no way to get it up that high without the tallest vertical element hitting the ceiling, so I removed it, and lost a lot of the VHF signal strength, but everything from 440MHZ on up was still pretty great. I took it home with me to try on my steel PC case, and I was pretty impressed. My apartment is on the second floor, and with the factory whip, MSPCS stuff was pretty weak, but with the discone, it's about 3X better, and I actually heard locomotives on the NS Chicago line a few miles away, so I guess I'm either going to get or make one as a project. I have a magnet mount that has been sitting unused that will work fine as a heavy base sitting in a drawer, and a bunch of brass rods from a long ago project, so I'm halfway there on parts already.

I just got one of these for my SDS200 yesterday. I have it installed in the second floor of my house and it is outstanding. I am getting things I never got before on the air bands and rail bands. I am very impressed with this indoor antenna.

 

[dmg1969]

I have somewhat of a similar issue. I had to move my Antennacraft ST-3 VHF/UHF out of the attic after getting a metal roof. I did a test mount on a 10' PVC mast at the corner of my elevated deck. That was enough to raise the antenna just about the roofline. It received excellent on both VHF and UHF. I decided to make it permanent install using standoff brackets mounted to the rim joist of the deck. I also went 3' higher so that the top of the mast was 13' off the decking. To the tip of the antenna was probably about 15'. After doing that, I noticed that my UHF reception went down quite a bit. VHF reception remains great. It is only about 18" from when I had the temporary test install and a few feet higher. I ended up taking it back down to 10' and it improved a little bit, but not as good as it was with the test install. I don't know if being 18" closer to the metal roof has anything to do with it. It is still around 8' away from the roof. Also, I did not ground it as I made it quick to take down any time it there is even talk of bad whether. I may end up temporarily moving it back to the exact spot it was when I first started to see if the reception returns to rule out static buildup. Once I find the sweet spot, I can look at grounding.