Use of 121.5mhz (Merged)
Can't say I've ever been distracted by practice pans, training fixes or any other "abuse" of 121.5 whilst monitoring it whether in the UK or anywhere else in the world. What I do get slightly frustrated at is the ear splitting squeal that erupts from my headset when someone is still making their PA, passing their arrival information or calling maintrol and 20 muppets all jump on the transmission to say "You're on guard". If you're one of the self-appointed guardians of 121.5 then perhaps you should go back and revise the operation of airborne transmitting/receiving equipment - if someone is still transmitting they cannot hear you - on a similar note if more than one of you transmits a reminder simultaneously once the original miscreant has finished - you block each other out and they still can't hear you. Keep up the good work 
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Read back only what is required. Don't use un-necessary words.
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121.5 and 243
Guys,
can you help resolve an argument.
I believe I am right in saying distress calls on 121.5 will be picked up on 243 ( 2nd harmonic ?), what about the other way round.
Say a mil flight was crossing pond and put out a distress would a civilian flight hear -carrier only- carrier and voice - or nothing, (assuming they were only monitoring 121.5).
Do civilian flights only monitor 121.5.
The dispute was over the fact that a mil distress call was claimed to have been heard on a 121.5 only beacon
ta
isca-isca
can you help resolve an argument.
I believe I am right in saying distress calls on 121.5 will be picked up on 243 ( 2nd harmonic ?), what about the other way round.
Say a mil flight was crossing pond and put out a distress would a civilian flight hear -carrier only- carrier and voice - or nothing, (assuming they were only monitoring 121.5).
Do civilian flights only monitor 121.5.
The dispute was over the fact that a mil distress call was claimed to have been heard on a 121.5 only beacon
ta
isca-isca
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I had a Friend who Once got Lost...... he thought to avoid embrassment he wud use 121.5 and carry out a Practice PAN!! London Centre told him that they were unable to except a Practise PAN at this Time!!! He thought CRAP! So, he ended up declearing a PAN afterall! He got a bit of a Bollocking from our CI!
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Civilian airplanes (airlines)
isca-isca -
xxx
Civilian airplanes only have VHF 121.5 capability.
We always select 121.5 on our nš 2 VHF radio and monitor.
It really should be on nš 1 in case of partial electrical system loss (favors nš 1).
It goes on nš 1 if on oceanic flights.
Absolutely no UHF equipment... so forget 243.0 for them.
Airplanes with HF also can use 2182 kHz as alternate guard frequency.
But HF is of limited use, and that frequency is bad for daytime.
xxx
Happy contrails
xxx
Civilian airplanes only have VHF 121.5 capability.
We always select 121.5 on our nš 2 VHF radio and monitor.
It really should be on nš 1 in case of partial electrical system loss (favors nš 1).
It goes on nš 1 if on oceanic flights.
Absolutely no UHF equipment... so forget 243.0 for them.
Airplanes with HF also can use 2182 kHz as alternate guard frequency.
But HF is of limited use, and that frequency is bad for daytime.
xxx
Happy contrails
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BelargUSA,
I thought that was the case, but am I right in saying a call from 121.5 will be picked up on 243 as it is the 2nd harmonic, if I am what about a 243 call being picked up on 121.5 as it is the 1st sub harmonic. Suppose there might also be a problem on voice one might be standard modulation the other ssb , I don't know.
ta
isca-isca
I thought that was the case, but am I right in saying a call from 121.5 will be picked up on 243 as it is the 2nd harmonic, if I am what about a 243 call being picked up on 121.5 as it is the 1st sub harmonic. Suppose there might also be a problem on voice one might be standard modulation the other ssb , I don't know.
ta
isca-isca
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Harmonics
isca-isca -
xxx
I happen to be (in the past) a radio "Ham" and know about harmonics.
At least for HF frequencies such as in the 10, 20 and 40 meter bands.
Did bothered neighbors around my antenna into their regular receivers.
But I could not say what would be the case if/when on VHF/UHF.
I never practiced with these frequencies.
xxx
Happy contrails
xxx
I happen to be (in the past) a radio "Ham" and know about harmonics.
At least for HF frequencies such as in the 10, 20 and 40 meter bands.
Did bothered neighbors around my antenna into their regular receivers.
But I could not say what would be the case if/when on VHF/UHF.
I never practiced with these frequencies.
xxx
Happy contrails
