2 meter question -- local weather interference?

[KB2GOM]

I run the Commuter Assistance Net on 146.94 here in Troy, NY.

Info here: Commuter Assistance Net

The repeater is apparently rock-solid: About

So here's the question: is it possible that local weather conditions can screw up local communications with a repeater?

I ask because, for the past two days, almost everyone has been checking into the net with "the crackles," and that is very atypical. Sometimes we get ducting from a repeater on Long Island, but there was no sign of it. So any insight the folks here might offer would be greatly appreciated.

 

[dlwtrunked]

Rather than weather itself, it is possible that something in the antenna installation could be a factor. These include:
1. A loose connector (until that has been checked, do not say "cannot be"--I have seen that before).
2. Something wrong on the antenna end. Yes hard to check. At least look at it with binoculars if needed.
3. What else is on the tower or near the installation? A problem with a nearby FM broadcast transmitter (particularly arcing) can be a cause of your problem. Is there any look metal (like hardware or cable support) on the tower or nearby--seen that happen with symptoms you describe.

You did not describe the weather--wind? rain? Did it go away when the weather changed?

 

[ecps92]

Yes - Weather [Local / Approaching and Departing] can improve or hamper VHF/UHF and higher at times

VHF Propagation Map

aprs.mennolink.org

IS the LI Repeater on the same PL tone ?

Likely you hearing a user or two who are triggering both Repeaters, not the LI Repeater, unless someone is linking
them locally via the input

Now as to Crackles etc, that could be something local [Arcing connections] water in the cables, etc etc

I run the Commuter Assistance Net on 146.94 here in Troy, NY.

Info here: Commuter Assistance Net

The repeater is apparently rock-solid: About

So here's the question: is it possible that local weather conditions can screw up local communications with a repeater?

I ask because, for the past two days, almost everyone has been checking into the net with "the crackles," and that is very atypical. Sometimes we get ducting from a repeater on Long Island, but there was no sign of it. So any insight the folks here might offer would be greatly appreciated.

 

[KB2GOM]

Rather than weather itself, it is possible that something in the antenna installation could be a factor. These include:
1. A loose connector (until that has been checked, do not say "cannot be"--I have seen that before).
2. Something wrong on the antenna end. Yes hard to check. At least look at it with binoculars if needed.
3. What else is on the tower or near the installation? A problem with a nearby FM broadcast transmitter (particularly arcing) can be a cause of your problem. Is there any look metal (like hardware or cable support) on the tower or nearby--seen that happen with symptoms you describe.

You did not describe the weather--wind? rain? Did it go away when the weather changed?

Weather: sunny calm, no approaching weather. Some stations, normally heard well, had horrible static. Happened over the past two mornings. We'll see what happens tomorrow.

 

[bb911]

I live in one of the Santa Ana wind prone areas of SoCal. The dry air associated with the winds can cause static, even on FM transmissions (AM aircraft can really get noisy). The noise on the FM bands isn't too bad, so it sounds like you have more severe problem(s). I agree with the post staying the crackling noise may be due to arcing type interference. I once had a problem with a fish aquarium heater that was in a home at least 100 yds away from my location.

 

[nd5y]

Crackling (not noise from just having a weak signal) is probably either a problem with the repeater receiver or interference from something, or loose hardware or poor connections at the repeater site.

 

[vagrant]

Go to the repeater site:
1. Use an AM and or FM radio and tune off frequency of any station. Do you hear the crackling at the same time?
2. Using a mobile or handheld, open up the squelch on the repeater input frequency (No PL). Are you hearing another signal on the same frequency?
3. Physically check the connections at the tower site. Save climbing for last, but use binoculars as previously noted. Any loose cables? They may not be disconnected, but no longer tied down.
4. Sweep the duplexer and whatever else is inline. Then connect a handheld or mobile radio to the coaxial cable and listen on the input frequency using the repeater antenna. Don't forget to check the SWR on the antenna.

At this point if everything seems okay, the culprit could still be at the antenna connection, but as nd5y noted, it may be the repeater receiver. You may want to share...oh wow I just read you have two repeaters transmitting on the same frequency. I read one is a Quantar, what is the other repeater that has been on the air for fifty seven years? When was the last time the duplexers were swept at both sites? On which repeater do you hear the crackling?

 

[KB2GOM]

Yes - Weather [Local / Approaching and Departing] can improve or hamper VHF/UHF and higher at times

VHF Propagation Map

aprs.mennolink.org

IS the LI Repeater on the same PL tone ?

Likely you hearing a user or two who are triggering both Repeaters, not the LI Repeater, unless someone is linking
them locally via the input

Now as to Crackles etc, that could be something local [Arcing connections] water in the cables, etc etc

Our repeater is open; no tone; don't know what the LI tone is.

Go to the repeater site:
1. Use an AM and or FM radio and tune off frequency of any station. Do you hear the crackling at the same time?
2. Using a mobile or handheld, open up the squelch on the repeater input frequency (No PL). Are you hearing another signal on the same frequency?
3. Physically check the connections at the tower site. Save climbing for last, but use binoculars as previously noted. Any loose cables? They may not be disconnected, but no longer tied down.
4. Sweep the duplexer and whatever else is inline. Then connect a handheld or mobile radio to the coaxial cable and listen on the input frequency using the repeater antenna. Don't forget to check the SWR on the antenna.

At this point if everything seems okay, the culprit could still be at the antenna connection, but as nd5y noted, it may be the repeater receiver. You may want to share...oh wow I just read you have two repeaters transmitting on the same frequency. I read one is a Quantar, what is the other repeater that has been on the air for fifty seven years? When was the last time the duplexers were swept at both sites? On which repeater do you hear the crackling?

I am not the repeater owner/controller, but the owner is in the commercial radio business, so I'm pretty sure that the old repeater is sitting there as a backup. I doubt that it is transmitting at the same time.

And -- and this is key -- everything was just fine until a couple of days ago.

Thanks to everyone for their comments. If the situation doesn't correct itself shortly, I'm sure the owner will be looking into it.

 

[wtp]

LI = long island.

 

[iMONITOR]

Commercial Filters | PAR Electronics | Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave listening enthusiasts

PAR Electronics Inc. Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave

www.parelectronics.com

 

[WB9YBM]

So here's the question: is it possible that local weather conditions can screw up local communications with a repeater?

I ask because, for the past two days, almost everyone has been checking into the net with "the crackles," and that is very atypical. Sometimes we get ducting from a repeater on Long Island, but there was no sign of it. So any insight the folks here might offer would be greatly appreciated.

Yes; I've noticed that when there's a big enough temperature swing (about twenty degrees) there'll be tropo ducting. Crackling, though, I've noticed is typically caused by a loose connection somewhere or a really strong source of sparking (ignition noise from a souped-up hot-rod nearby, for example).

 

[Project25_MASTR]

Quantars are fairly robust machines. Great receive sensitivity, and one of the longest modern products Motorola supported (they were introduced around 1994 and Motorola only stopped supporting them a few years back). They have two primary failure points...power supply cooling fan (if it fails the power supply will overheat and harakiri itself) or the PA cooling fans (which do the same thing but nuke the PA). Once you overcome those two issues...the repeaters will transmit for years (continuously).

That being said, the biggest introductions of noise in a repeater system are moisture intrusion into the feedline, damaged antenna system, PA failure, or alignment issue. The problem is...you really can't diagnose any of it without being on site.

 

[ecps92]

If your Repeater doesn't use tone, then the LI tone has no impact.

Our repeater is open; no tone; don't know what the LI tone is.


I am not the repeater owner/controller, but the owner is in the commercial radio business, so I'm pretty sure that the old repeater is sitting there as a backup. I doubt that it is transmitting at the same time.

And -- and this is key -- everything was just fine until a couple of days ago.

Thanks to everyone for their comments. If the situation doesn't correct itself shortly, I'm sure the owner will be looking into it.

 

[KB2GOM]

Got the answer: weird atmospheric conditions due to a temperature inversion (not uncommon this time of year), confirmed by the Albany, NY, National Weather Service office.

Thanks to all for your input!

 

[dlwtrunked]

Weather: sunny calm, no approaching weather. Some stations, normally heard well, had horrible static. Happened over the past two mornings. We'll see what happens tomorrow.

But that is not the sort of problem he reported - "crackles" on rock solid signals.. Things I listed will sound like that.

 

[vagrant]

What is nice about a forum is that someone down the line will be able to use the information shared.

 

[KB2GOM]

Got the answer: weird atmospheric conditions due to a temperature inversion (not uncommon this time of year), confirmed by the Albany, NY, National Weather Service office.

Thanks to all for your input!

Also, the weather was extremely dry.

 

[dlwtrunked]

Also, the weather was extremely dry.

Dry and wind can cause static in some antenna installations. We have that problem here. If you hear the "crackles" again, as one persons crackles are not anothers, see if you can find a way to record them and put them somewhere for us to hear. It will help in identifying. I am not certain that you have found the cause.

 

[ecps92]

But we now return to the Crackle issue, is this occuring All the time ?

And were you hearing the LI Repeater or a couple users using the LI Repeater.
To hear the actual Repeater getting into your repeater the pairs would have to be reversed and/or someone patching/linking.
To hear only certain users, would indicate the band opening [as if occuring today see VHF Propagation Map ]

To remedy the occasional band opening, I would PL/DPL the input freq of the repeater

Got the answer: weird atmospheric conditions due to a temperature inversion (not uncommon this time of year), confirmed by the Albany, NY, National Weather Service office.

Thanks to all for your input!

 

[KB2GOM]

But we now return to the Crackle issue, is this occuring All the time ?

And were you hearing the LI Repeater or a couple users using the LI Repeater.
To hear the actual Repeater getting into your repeater the pairs would have to be reversed and/or someone patching/linking.
To hear only certain users, would indicate the band opening [as if occuring today see VHF Propagation Map ]

To remedy the occasional band opening, I would PL/DPL the input freq of the repeater

Crackles are now gone. Almost everyone sounds like they are in a recording studio. Pretty sure the atmospheric inversion and the dry air are the culprits.