| Author |
Message |
bhimanipankaj
Guest
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 Posted:
Thu Dec 01, 2005 9:15 am Post subject:
Open challange target |
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Dear Friends......
Really new Idea with new challange,
If anybody can design a device or system which putting next to TV o
outside the TV box near the tuner section can detect which frequency i
selected or which channel is selected.
You can use anything like RF, Ultrasonic, or any idea u want, just yo
can't connect anything physically to the tuner.
Enjoy designing
Pankaj Bhimani |
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Clifford Heath
Guest
|
| Posted:
Thu Dec 01, 2005 9:15 am Post subject:
Re: Open challange target |
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bhimanipankaj wrote:
| Quote: | Really new Idea with new challange,
|
Really old idea that's been implemented in roaming
trucks for at least three decades. Yawn. |
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Peter
Guest
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| Posted:
Thu Dec 01, 2005 4:44 pm Post subject:
Re: Open challange target |
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"bhimanipankaj" <bhimanipankaj@gmail.com> wrote in message
news:3radncovzsoT5BPenZ2dnUVZ_tadnZ2d@giganews.com...
| Quote: |
Dear Friends......
Really new Idea with new challange,
If anybody can design a device or system which putting next to TV or
outside the TV box near the tuner section can detect which frequency is
selected or which channel is selected.
You can use anything like RF, Ultrasonic, or any idea u want, just you
can't connect anything physically to the tuner.
Enjoy designing
Pankaj Bhimani
|
Detect the frequency of the local oscillator, which as somebody else has
mentioned has been used in the UK for decades. The real challenge would be
to use ultrasonic to do it.
Peter |
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Meindert Sprang
Guest
|
| Posted:
Thu Dec 01, 2005 5:15 pm Post subject:
Re: Open challange target |
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"Peter" <moocowmoo@newprovidence.demon.co.uk> wrote in message
news:dmmk4s$ptq$1$830fa795@news.demon.co.uk...
| Quote: |
Detect the frequency of the local oscillator, which as somebody else has
mentioned has been used in the UK for decades. The real challenge would be
to use ultrasonic to do it.
|
And what if you dont't know whether the tuner uses up or down conversion and
it's MF?
Meindert |
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Paul Keinanen
Guest
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| Posted:
Thu Dec 01, 2005 5:15 pm Post subject:
Re: Open challange target |
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On Thu, 1 Dec 2005 13:04:34 +0100, "Meindert Sprang"
<mhsprang@NOcustomSPAMware.nl> wrote:
| Quote: | "Peter" <moocowmoo@newprovidence.demon.co.uk> wrote in message
news:dmmk4s$ptq$1$830fa795@news.demon.co.uk...
Detect the frequency of the local oscillator, which as somebody else has
mentioned has been used in the UK for decades. The real challenge would be
to use ultrasonic to do it.
And what if you dont't know whether the tuner uses up or down conversion and
it's MF?
|
While non-standard IF frequencies and local oscillators can be used to
fool e.g. radar detector detectors, it would be quite problematic to
implement on a TV receiver.
I have never seen a TV-tuner that would do upconversion. Upconversion
is mainly used in HF general conversion receiver with the first IF in
the 40-90 MHz range or in spectrum analyzers with the first IF at 2-4
GHz.
The TV IF is in the 30-40 MHz area for historical reasons and since
SAW filters are used these days, it would be quite hard to do some
special arrangements.
To cover the Band I VHF channels in the 47-68 MHz area, the local
oscillator (LO) would have to be above the received channel (Rx) to
keep the local oscillator tuning range reasonable. Running the LO
below the Rx frequency also creates the problem of LO harmonics
hitting the received channel. When the LO is above the Rx frequency,
the harmonics can never hit the received frequency.
Anyway, since the LO must be above RF on Band I, the IF spectrum is
inverted, moving the sound carrier from the top end of the channel to
the bottom of the IF passband. Sound traps etc must be set at this
frequency.
While it would technically be possible to put the LO below Rx on VHF
band III and UHF IV/V, this would also require moving the IF sound
trap to the opposite end of the IF-passband for these channels.
Thus, the LO is above Rx also on these channels to avoid this
inconvenience.
Paul |
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bhimanipankaj
Guest
|
| Posted:
Fri Dec 09, 2005 9:15 am Post subject:
Re: Open challange target |
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Guys thanx very much for lots of reply
and thanx to all who instead of finding solution trying to proov
themselve the tech geeks
But the overall challange is I dont want to open the TV box and using an
wireless sensors i want to finish the task.
whtever channel is selected by pressing keys from remote then the tune
will allow that RF I want to detect without opening the box or withou
connecting a single wire to TV .
Thats all
| Quote: | On Thu, 1 Dec 2005 13:04:34 +0100, "Meindert Sprang"
mhsprang@NOcustomSPAMware.nl> wrote:
"Peter" <moocowmoo@newprovidence.demon.co.uk> wrote in message
news:dmmk4s$ptq$1$830fa795@news.demon.co.uk...
Detect the frequency of the local oscillator, which as somebody els
has
mentioned has been used in the UK for decades. The real challeng
would be
to use ultrasonic to do it.
And what if you dont't know whether the tuner uses up or down conversio
and
it's MF?
While non-standard IF frequencies and local oscillators can be used to
fool e.g. radar detector detectors, it would be quite problematic to
implement on a TV receiver.
I have never seen a TV-tuner that would do upconversion. Upconversion
is mainly used in HF general conversion receiver with the first IF in
the 40-90 MHz range or in spectrum analyzers with the first IF at 2-4
GHz.
The TV IF is in the 30-40 MHz area for historical reasons and since
SAW filters are used these days, it would be quite hard to do some
special arrangements.
To cover the Band I VHF channels in the 47-68 MHz area, the local
oscillator (LO) would have to be above the received channel (Rx) to
keep the local oscillator tuning range reasonable. Running the LO
below the Rx frequency also creates the problem of LO harmonics
hitting the received channel. When the LO is above the Rx frequency,
the harmonics can never hit the received frequency.
Anyway, since the LO must be above RF on Band I, the IF spectrum is
inverted, moving the sound carrier from the top end of the channel to
the bottom of the IF passband. Sound traps etc must be set at this
frequency.
While it would technically be possible to put the LO below Rx on VHF
band III and UHF IV/V, this would also require moving the IF sound
trap to the opposite end of the IF-passband for these channels.
Thus, the LO is above Rx also on these channels to avoid this
inconvenience.
Paul
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Hans-Bernhard Broeker
Guest
|
| Posted:
Fri Dec 09, 2005 5:15 pm Post subject:
Re: Open challange target |
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bhimanipankaj <bhimanipankaj@gmail.com> wrote:
| Quote: | whtever channel is selected by pressing keys from remote then the tuner
will allow that RF I want to detect without opening the box or without
connecting a single wire to TV .
|
In that case, your best bet might very well be to listen in on the
TV's remote. Universal replacement remotes demonstrate this is
viable.
--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain. |
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