TV sounds
TV sounds
I am interested to know what the TV video signals sound like on 6m, having never heard any. Is there an audio file available that I could listen to? I do hear what I believe to be carriers on the band but perhaps I am mistaken. I read with interest various members of this group reporting hearing TV signals, but I remaim oblivious to what this actually is. I also wait anxiously to hear a real live qso sometime!
Grant, Brisbane, QG62ll
Achieving more with less.
Achieving more with less.
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VK4BKP
I'm not sure what type of transceiver you are using. Is it one that only receives between 50-54 or will it tune out of band? There are no vision carriers between 50-54 megs, although 49.750 when strong will bleed over 50 megs.
In SSB mode TV vision carriers mainly produce a tone at the centre frequency just like any carrier but with a little buzz present. In AM mode they tend to buzz louder. When strong they can cover several MHz.
There are a couple of sound channels on 50.740/750/760 for New Zealand TV and CH 0 Wagga and Tamworth are on 51.740 and 51.760. Again it depends on your radio. Modern multimode radios like the IC-706 have wideband FM and the sound carrier will sound similar to an FM station. If you have an older rig with only narrow band FM it will sound distorted like it's overmodulated/overdeviated.
The above mentioned are what analogue carriers sound like. Digital TV carriers just sound like hiss and don't seem to have a pronounced main carrier like the analogue ones do and seem to spread their power evenly over about 6 megs. Digital carriers are pretty useless with an analogue receiver for predicting openings.
I will miss the analogue TV transmissions when they are turned off. I have been a TV DXer since the late 70's and have collected many test patterns from all over the country and also China. Because they are very high power they make excellent beacons. They are also excellent for listening to meteors. Almost any time of the day or night if I tune to 46.171 or 46.240 the meteors will be heard pinging away. Just heard one up to S7 as I type on Toowoomba 46.171. The doppler shifted pings are really cool the way they change pitch.
If you pm me your email address I could send you a recording or even a video if your connection is fast enough.
In SSB mode TV vision carriers mainly produce a tone at the centre frequency just like any carrier but with a little buzz present. In AM mode they tend to buzz louder. When strong they can cover several MHz.
There are a couple of sound channels on 50.740/750/760 for New Zealand TV and CH 0 Wagga and Tamworth are on 51.740 and 51.760. Again it depends on your radio. Modern multimode radios like the IC-706 have wideband FM and the sound carrier will sound similar to an FM station. If you have an older rig with only narrow band FM it will sound distorted like it's overmodulated/overdeviated.
The above mentioned are what analogue carriers sound like. Digital TV carriers just sound like hiss and don't seem to have a pronounced main carrier like the analogue ones do and seem to spread their power evenly over about 6 megs. Digital carriers are pretty useless with an analogue receiver for predicting openings.
I will miss the analogue TV transmissions when they are turned off. I have been a TV DXer since the late 70's and have collected many test patterns from all over the country and also China. Because they are very high power they make excellent beacons. They are also excellent for listening to meteors. Almost any time of the day or night if I tune to 46.171 or 46.240 the meteors will be heard pinging away. Just heard one up to S7 as I type on Toowoomba 46.171. The doppler shifted pings are really cool the way they change pitch.
If you pm me your email address I could send you a recording or even a video if your connection is fast enough.
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VK3OT
Re: TV sounds
Heaps of data on sound files of what TV video sounds like.vk4jaz wrote:I am interested to know what the TV video signals sound like on 6m, having never heard any. Is there an audio file available that I could listen to? I do hear what I believe to be carriers on the band but perhaps I am mistaken. I read with interest various members of this group reporting hearing TV signals, but I remaim oblivious to what this actually is. I also wait anxiously to hear a real live qso sometime!
Tune in to 57.750
It sound slike that only usuually weaker with fading and phase distortion.
46.172
46.260 (bad example it has buzz)
46.240
49.750 +/-
48.250
45.250 +/-
http://www.minecost.com/hamstuff/
http://www.dxzone.com/catalog/Internet_ ... io/Sounds/
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VK3SIX
Re: video carriers
There are quite a few non standard chinese university transmission between 50 and 51 mhz using SECAM video