What Is the Best Way to Send FM Program Audio to a Sister Station 40 Miles Away?

[Chuck]

The plan was for a phased multibay antenna to add nulls in specific directions toward cochannels and adjacents, not to build a single antenna. The only requirement is that they be identical. Cheap ones would work just fine. Like you say, you might have to replace them though.

I've done the "cheap ones" before. Call me "naturally thrifty," if you like. (That's polite for "cheap.)

Cheap antennas for broadcasting are false economy. I've learned this the hard way. Even though they often work very well, they do not hold up very well to severe weather and wind. What you save up front, you will eventually make up by paying tower climbers to fix or replace, the flimsy "cheap antenna." While these consumer antennas may be fine on the roof of your house, the conditions on a tower, a couple of hundred feet off the ground, are quite a bit more severe.

If it costs you $450 to have somebody climb your tower to mess with your $89 antenna, the second time you have this done will prove that you were better off with a truly heavy duty antenna that required no service.

 

[ChiefEngineer]

Rather than build an antenna, or going to other extremes, how about popping for $600-700 and get a great receive antenna from Katerine-Scala. They make both log-periodic and yagis that are very good at receiving distant signals. http://www.kathrein-scala.com/fm_log.php Thay are built incredibly well, so you won't have to replace it every couple of years.

Couple that with a good translator style receiver, such as the BW Broadcast RBR-X1 http://www.fm-receiver.com/ and you have a very reliable combination.

A 40 mile hop should be no problem at all.

I would never say 40 miles OTA is easy or no problem. Is this from a General manager or an Engineer? Is this one community of License that is 40 miles from your other station's community of License? That doesn't mean the path is 40 miles. This could well be 60 miles from transmitter to receive site, or more. I have a host of CLass A stations that regularly have a studio or tower that is another 6-10 miles from the city they are Licensed to.

I used to regularly have a General Manager or Engineer who always wanted a quick fix. The time they wanted me to install a switch for the automation to start and stop it. "Just install a switch." This seemed simple. "Just a two wire switch" one said. Not considering the Schaeffer automation had a 50 wire remote and the place they wanted "the switch" "a two wire switch" was in a room that had already had so many switches installed there was no no wire available (not one) to run the 50 wires from the other location a quarter mile away by conduit.

Kathrein Scala makes great antennas and one is designed to null adjacent stations. Consider the band openings we have had recently. WFIU Bloomington (IU get it?) is a grandfathered Class B. Their translator in Columbus regularly looses signal even though it is less than 30 miles from the source.

This is not dependable. Since they are listener supported and the translator fills holes you can always tune in the powerhouse FM unless it is wiped out by another station.

This a Class B and I can normally hear it over 50 miles away on a tabletop radio. The Scala Log Periodic would take care of this one might think.

We have a Class A that changed communities. The new community is less than 20 miles from community A but the transmitter site is an extra 6 air miles. This was thought to be a great fix for replacing a class B in community B. At the county fair in community B the loudspeaker carrying the station lost the station and picked up another station during a band enhancement. This was public and this is regularly related by people who heard it. It was an indication the new station was nothing like the old station that covered the community. Credibility has always been an issue.

If you are a commercial station and there is any real consideration this station doing the simulcast needs to be credible. Your competitor is set to call all your advertisers when your station fades out and another station replaces it. It's much more fun to do this when your station (Solid Rock The Pig) is rebroadcasting a mom and pop station (If any are left) with market reports and local news for a town 100 miles away. "Hey guy "The Pig" changed their format so why not place all your account funds with us." I hear some under perfoming Sales Manager and GM 's shoes headed to your office or cubicle now. And BTW you will forget your wife is in labor or your kid is being baptized or your mother is being buried to fix this NOW.

Before you haul that log periodic up the tower consider the band openings we have had this year alone. Use RDS to feed the station with a cutover to ip when your unique rds fades.

 

[everydayguy]

On behalf of my friend and colleague dx7, thanks to everyone for your advice so far.

Chief, it's actually 38 miles from the main station's transmitter site to the sister stations receive-point, but tropo ducting can be a big problem for us from time to time (we're near the Gulf of Mexico.)

It does seem that retransmitting the main signal from an off-air receiver & directional antenna makes some sense except for the ocassional tropo and the fact that the off-the-air signal is already being processed before it gets to the processor at the sister station's TX site.

As I say, we really appreciate all the input from this board.

 

[Chuck]

I would never say 40 miles OTA is easy or no problem. Is this from a General manager or an Engineer? Is this one community of License that is 40 miles from your other station's community of License? That doesn't mean the path is 40 miles. This could well be 60 miles from transmitter to receive site, or more. I have a host of CLass A stations that regularly have a studio or tower that is another 6-10 miles from the city they are Licensed to.

You obviously are not familiar with the BW Broadcast tuner I mentioned. I suggest you read its specs. That’s why I posted a link. It can be programmed to fall back on to auxiliary source like an IP feed (or even a USB Memory stick) if it loses the originating station's RDS feed. You can also program it to simply shut off the transmitter if the RDS is lost. There are lots of ways it can be utilized. It contains its own stereo generator which reforms the composite signal to compensate for other reception problems. It even passes your originating station's RDS text, such as song title info, or whatever you are broadcasting.

I'm using this identical set up on a 56 mile line of site hop. The originating station is a Class A on a 490 foot tower. It works fine. Try it - you'll like it.

By the way, I am both an engineer and a station owner/manager. I even belong to SBE.