DXing translator content?

[w9wi]

Actually, I seem to recall there being a rule that a translator must shut off when it loses its parent signal... Either by some subaudible method as w9wi described or by using the RDS carrier as a guide, etc.

74.1231(e) which says:
"An FM translator shall not deliberately retransmit the signals of any station other than the station it is authorized to retransmit. Precautions shall be taken to avoid unintentional retransmission of such other signals."

I suspect the use of a directional receiving antenna aimed at the desired primary station and some kind of signal-strength-operated switch (to turn the translator off if the input signal is too weak) are probably considered adequate to comply with this regulation.

(but keep in mind I'm a TV engineer, not a radio lawyer!)

For what it's worth, the same paragraph appears in the regulations for TV translators.

 

[gr8oldies]

Ham repeaters often has "PL" subaudible tones to prevent constant "kerchunking" of the repeater during band openings, or even to prevent non-members from using the repeater. I'd think a subaudible tone might do the same thing with a broadcast translator.

 

[nd2023]

However, if there's tropo, then the translator will receive a signal strength from another station even stronger than the parent station, which is why it will rebroadcast the other station.

 

[w9wi]

Ham repeaters often has "PL" subaudible tones to prevent constant "kerchunking" of the repeater during band openings, or even to prevent non-members from using the repeater. I'd think a subaudible tone might do the same thing with a broadcast translator.

CTCSS tones are subaudible on an amateur (or commercial two-way) station whose frequency response is limited to 300-3000Hz. They'd be plainly audible on a FM broadcast station (or translator) whose low end goes down well below 100Hz. IIRC the lowest valid CTCSS tone is 67Hz.

I suppose you could use a lower non-standard tone. Supersonic (somewhere in the SCA band) is probably a lot safer.

 

[eyg2181]

you know what would be cool, if you live right near a translater tower, get one of those mpe player/ipod FM transmitters, tune it to the same frequency as the translator is picking up, then the translater will give your station full market coverage.

 

[tomservo]

you know what would be cool, if you live right near a translater tower, get one of those mpe player/ipod FM transmitters, tune it to the same frequency as the translator is picking up, then the translater will give your station full market coverage.

They're probably too weak to work.

After our local translator came on I realized that the station it was picking up happened to be the same frequency I used to transmit my XM through the house, and not the one listed in the FCC authorization. So...

I brought my little Ramsay kit transmitter up to the translator site, turned it on, and... Nothing. It just isn't strong enough, apparently. The local translator appears to use a vertical whip for reception and a single bay (Shivley?) way down low on the tower to transmit. I figured it wasn't very directional, but it must be. Although not directional enough to get several different stations fighting it out in the morning, some from 200+ miles away.

 

[Grrrradio]

A watt into a properly matched dipole will usually do it (I tragically miscalculated the binary DIL switch settings on my pirate transmitter one day as I was attempting to tune it up...)