What voltage for 18 inch satellite dishes?

[mm]

What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It
needs power but the only manual I can find says it uses the same
voltage as the dish, and doesn't say how much the dish uses.


Thanks for any help on all my questions.

P. S. I also took off the center part, the receiver or whatever, and
sold it for a dollar or two at a hamfest. They sell new for 50
dollars but tha's okay.

 

[Jeff Liebermann]

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com>
wrote:

What voltage is meant to be used by 18 inch satellite dishes?
AC or DC?

DC. For simple LNB's, 13V for left hand circular polarization. 18V
for right hand. That corresponds to the odd channels and the even
channels (or the reverse in case I got it backwards). If you're using
a DiSEqC switch, there's also a 22KHz control tone to switch outputs.
Life gets really complexicated if you have a 5 LNB dish.

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It
needs power but the only manual I can find says it uses the same
voltage as the dish, and doesn't say how much the dish uses.

Ugh. I don't know how the VHF/UHF antenna is switched.

Thanks for any help on all my questions.

P. S. I also took off the center part, the receiver or whatever, and
sold it for a dollar or two at a hamfest. They sell new for 50
dollars but tha's okay.

You can also build a wi-fi range extender with the dish:
<http://www.findmorecollectibles.com/wifi.html>
<http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/>
<http://www.qsl.net/ki7cx/wgfeed.htm>
<http://www.weijand.nl/wifi/>

 

[Arfa Daily]

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:evk265hkec4l71kdbnc07u894qhc5kt9vi@4ax.com...

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com
wrote:

What voltage is meant to be used by 18 inch satellite dishes?
AC or DC?

DC. For simple LNB's, 13V for left hand circular polarization. 18V
for right hand. That corresponds to the odd channels and the even
channels (or the reverse in case I got it backwards). If you're using
a DiSEqC switch, there's also a 22KHz control tone to switch outputs.
Life gets really complexicated if you have a 5 LNB dish.

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It
needs power but the only manual I can find says it uses the same
voltage as the dish, and doesn't say how much the dish uses.

Ugh. I don't know how the VHF/UHF antenna is switched.

Thanks for any help on all my questions.

P. S. I also took off the center part, the receiver or whatever, and
sold it for a dollar or two at a hamfest. They sell new for 50
dollars but tha's okay.

You can also build a wi-fi range extender with the dish:
http://www.findmorecollectibles.com/wifi.html
http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/
http://www.qsl.net/ki7cx/wgfeed.htm
http://www.weijand.nl/wifi/

Circular polarisation for US DBS, Jeff ? Over this side of the pond, it's
vertical and horizontal polarisation for alternate channels or whatever, but
with the same selection / LNB powering voltages, and additional switching by
22kHz tone, the same.

Arfa

 

[Meat Plow]

On Fri, 17 Jul 2009 18:27:05 -0400, mm
<NOPSAMmm2005@bigfoot.com>wrote:

What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It
needs power but the only manual I can find says it uses the same
voltage as the dish, and doesn't say how much the dish uses.


Thanks for any help on all my questions.

P. S. I also took off the center part, the receiver or whatever, and
sold it for a dollar or two at a hamfest. They sell new for 50
dollars but tha's okay.

9 - 13 VDC shud power it.

 

[Jeff Liebermann]

On Sat, 18 Jul 2009 09:54:43 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

Circular polarisation for US DBS, Jeff ? Over this side of the pond, it's
vertical and horizontal polarisation for alternate channels or whatever, but
with the same selection / LNB powering voltages, and additional switching by
22kHz tone, the same.

DirecTV and Dish are both circular polarization.
HughesNet internet is linear (vertical or horizontal) polarization.
FTA (free to air) transmissions are all linear polarization.
Broadcast downlinks (FSS) are all linear polarization.

<http://en.wikipedia.org/wiki/Low-noise_block_converter>
"Most North American DBS signals use circular polarization, instead of
linear polarization, therefore requiring a different LNB type for
proper reception. In this case, the polarization must be adjusted
between clockwise and counterclockwise, rather than horizontal and
vertical."

This explains it in detail:
<http://www.abadss.com/forum/102-faq-how/5880-understand-lnbs-standard-linear-circular-universal-lnb-lnbf-stacked.html>



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[mm]

On Fri, 17 Jul 2009 22:03:07 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com
wrote:

What voltage is meant to be used by 18 inch satellite dishes?
AC or DC?

DC. For simple LNB's, 13V for left hand circular polarization. 18V
for right hand.

Wow. That's amazing.

Thanks to everyone. I should be able to get this working, plus I have
3 amplified antennas in my attic. One or two of them are broken, but I
think I have enough for myself and a friend and his landlady, both of
whom have had very little tv since digital.

BTW, I remember now I sold that thing in the center of the dish for
one or two dollars BEFORE I saw it for sale at Radio Shack for 50
dollars, but that's still okay.

That corresponds to the odd channels and the even
channels (or the reverse in case I got it backwards). If you're using
a DiSEqC switch, there's also a 22KHz control tone to switch outputs.
Life gets really complexicated if you have a 5 LNB dish.

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It
needs power but the only manual I can find says it uses the same
voltage as the dish, and doesn't say how much the dish uses.

Ugh. I don't know how the VHF/UHF antenna is switched.

Thanks for any help on all my questions.

P. S. I also took off the center part, the receiver or whatever, and
sold it for a dollar or two at a hamfest. They sell new for 50
dollars but tha's okay.

You can also build a wi-fi range extender with the dish:
http://www.findmorecollectibles.com/wifi.html
http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/
http://www.qsl.net/ki7cx/wgfeed.htm
http://www.weijand.nl/wifi/

 

[AZ Nomad]

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com> wrote:

What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It

Dishes are passive devices; they are not powered by anything but incoming RF
energy.

A good start would be to learn the difference between a dish,
LNB, and receiver.

 

[Arfa Daily]

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:0cs3659cp4opu7ne8ntktnvtpvfcl1t79m@4ax.com...

On Sat, 18 Jul 2009 09:54:43 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

Circular polarisation for US DBS, Jeff ? Over this side of the pond, it's
vertical and horizontal polarisation for alternate channels or whatever,
but
with the same selection / LNB powering voltages, and additional switching
by
22kHz tone, the same.

DirecTV and Dish are both circular polarization.
HughesNet internet is linear (vertical or horizontal) polarization.
FTA (free to air) transmissions are all linear polarization.
Broadcast downlinks (FSS) are all linear polarization.

http://en.wikipedia.org/wiki/Low-noise_block_converter
"Most North American DBS signals use circular polarization, instead of
linear polarization, therefore requiring a different LNB type for
proper reception. In this case, the polarization must be adjusted
between clockwise and counterclockwise, rather than horizontal and
vertical."

This explains it in detail:
http://www.abadss.com/forum/102-faq-how/5880-understand-lnbs-standard-linear-circular-universal-lnb-lnbf-stacked.html

That's interesting. I wonder what the perceived advantage of using circular
over linear polarisation is ? I can see that polarisation twist from passage
of the signal through the atmosphere would be eliminated, and also skew
caused by your E-W position with respect to the bird. Do you think that's
the reason ? I didn't realise that a c.p, LNB was effectively just an l.p
LNB with a signal 'de-spinner' (lump of ferrite ?) in the feed. As long as
DBS has been going in Europe, which is quite a lot of years now if you go
back to the old analogue birds, c.p. has never been used, which is why I'm
not too familiar with it as applied to microwave signals.

Many of the LNBs here are now multis to allow use of receivers with dual
independant tuners, and the multi-room service which allows two dual tuner
receivers to be connected to the same dish. Do you have multis like this
that still work with c,p, ?

Arfa

 

[Jeff Liebermann]

On Sun, 19 Jul 2009 01:39:38 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

That's interesting. I wonder what the perceived advantage of using circular
over linear polarisation is ?

Perception is everything, except in this case.

There are some technical advantages to CP. With a single LNB, it's
possible to install the dish with only elevation and azimuth, and no
consideration for tilt. However, with 2 or more LNB's, it is
necessary to align the dish tilt along the ecliptic. Similarly, with
CP at the satellite end, the bird could theoretically not worry about
alignment. However, none of the satellites are that crude. There's
also an advantage when dealing with reflections. Odd order
reflections change the sense of the signal, which then is ignored by
the LNB. However, if the reflections are that bad, there's going to
be some deterioration even with opposite sense cancellation.

However, that's not why the US has CP and the EU is linear
polarization. The US has a long history of *NOT* doing whatever
Europe is doing. EU uses CODFM for DTV, US uses 4VSB. Cellular is
mostly GSM in EU, but a mix of CDMA and GSM in the US. Our cellular
bands are 800/1900, while the EU is 900/1800. Europe is 220VAC 50Hz,
US is 117VAC 60Hz. EU used PAL, US used NTSC. EU is metric, US is
weird. Any semblence of a concerted effort to be different by both
parties is probably intentional.

Incidentally, you can buy LNB's that do both linear and circular
polarization.
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=380135119430>

I can see that polarisation twist from passage
of the signal through the atmosphere would be eliminated,

That's Faraday rotation, which isn't much of a problem at 13GHz.
<http://en.wikipedia.org/wiki/Faraday_effect>
It's really bad at L-band, C-band, and lower frequency terrestrial
point to point signals, but not for geosync birds at Ku band.
<http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=875205&isnumber=18933>
Incidentally, that's another reason why GPS systems (1.2-1.6GHz) are
circularly polarized.

and also skew
caused by your E-W position with respect to the bird. Do you think that's
the reason ?

You're asking my opinion? Well, the current fashion is for political
leaders and organization to make technical decisions, so my suspicion
is that if there were an even more obscure polarization method, the US
would have adopted it.

I didn't realise that a c.p, LNB was effectively just an l.p
LNB with a signal 'de-spinner' (lump of ferrite ?) in the feed.

Dunno. I don't recall seeing anything of the sort when I looked
inside. I'll see what I can find instead of guessing.

As long as
DBS has been going in Europe, which is quite a lot of years now if you go
back to the old analogue birds, c.p. has never been used, which is why I'm
not too familiar with it as applied to microwave signals.

Many of the LNBs here are now multis to allow use of receivers with dual
independant tuners, and the multi-room service which allows two dual tuner
receivers to be connected to the same dish. Do you have multis like this
that still work with c,p, ?

Yep. 3 and 5 LNB's per dish is quite common for the HDTV systems that
need to hear 4 different slots on both Ka and Ku band. Here are some:
<http://www.tech-faq.com/directv-satellite-dishes.shtml>
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150346997564>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[mm]

On Sat, 18 Jul 2009 17:58:10 -0500, AZ Nomad
<aznomad.3@PremoveOBthisOX.COM> wrote:

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com> wrote:
What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It

Dishes are passive devices; they are not powered by anything but incoming RF
energy.

Items sold as dishes include amplifers.

A good start would be to learn the difference between a dish,
LNB, and receiver.

A good start on what?

I'm not really interested in an electronics lesson. I just want to
know what voltage would power the amplifier on the VHF/UHF antenna
that surrounds the dish. The manual says it uses the same voltage
that dish does, or something like that. Maybe you can write the
manual's author.

I'll go with one of the helpful answers.

 

[Michael A. Terrell]

mm wrote:

On Sat, 18 Jul 2009 17:58:10 -0500, AZ Nomad
aznomad.3@PremoveOBthisOX.COM> wrote:

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com> wrote:
What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It

Dishes are passive devices; they are not powered by anything but incoming RF
energy.

Items sold as dishes include amplifers.

A good start would be to learn the difference between a dish,
LNB, and receiver.

A good start on what?

I'm not really interested in an electronics lesson. I just want to
know what voltage would power the amplifier on the VHF/UHF antenna
that surrounds the dish. The manual says it uses the same voltage
that dish does, or something like that. Maybe you can write the
manual's author.

I'll go with one of the helpful answers.

Why don't you just go away? You gave no brand or model number, or
anything else that would let anyone help you.


--
You can't have a sense of humor, if you have no sense!

 

[Nigel Feltham]

Arfa Daily wrote:

"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:0cs3659cp4opu7ne8ntktnvtpvfcl1t79m@4ax.com...
On Sat, 18 Jul 2009 09:54:43 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

Circular polarisation for US DBS, Jeff ? Over this side of the pond, it's
vertical and horizontal polarisation for alternate channels or whatever,
but
with the same selection / LNB powering voltages, and additional switching
by
22kHz tone, the same.

DirecTV and Dish are both circular polarization.
HughesNet internet is linear (vertical or horizontal) polarization.
FTA (free to air) transmissions are all linear polarization.
Broadcast downlinks (FSS) are all linear polarization.

http://en.wikipedia.org/wiki/Low-noise_block_converter
"Most North American DBS signals use circular polarization, instead of
linear polarization, therefore requiring a different LNB type for
proper reception. In this case, the polarization must be adjusted
between clockwise and counterclockwise, rather than horizontal and
vertical."

This explains it in detail:

http://www.abadss.com/forum/102-faq-how/5880-understand-lnbs-standard-linear-circular-universal-lnb-lnbf-stacked.html



That's interesting. I wonder what the perceived advantage of using
circular over linear polarisation is ? I can see that polarisation twist
from passage of the signal through the atmosphere would be eliminated, and
also skew caused by your E-W position with respect to the bird. Do you
think that's the reason ? I didn't realise that a c.p, LNB was effectively
just an l.p LNB with a signal 'de-spinner' (lump of ferrite ?) in the
feed. As long as DBS has been going in Europe, which is quite a lot of
years now if you go back to the old analogue birds, c.p. has never been
used, which is why I'm not too familiar with it as applied to microwave
signals.

Not completely true - the UK's old BSB satellite service used circular
plolarisation (quoted as right hand circular which I'm assuming means
clockwise) until the system was killed off by SKY's dodgy dealings - they
persuaded the UK government that BSB would need 2 satellites so there would
be a backup and that they'd need to use the more expensive D-MAC standard
to get good enough picture quality.

The result being it cost a fortune to get new box hardware designed and put
2 satellites up just to broadcast 5 channels (which couldn't be expanded
without launching another 2 satellites) when at the same time SKY were
exempt from UK satellite broadcast restrictions due to uplinking from
Luxembourg and were allowed to rent space on an Astra satellite with space
for 16 channels and using cheaper PAL receivers that were already designed
and available.

When BSB closed down (after only 6 months of broadcasting) the 2 satellites
were sold to Scandinavian broadcasters who switched to D2-MAC and used them
until 2003.

 

[Meat Plow]

On Sat, 18 Jul 2009 19:56:09 -0700, Jeff Liebermann
<jeffl@cruzio.com>wrote:

On Sun, 19 Jul 2009 01:39:38 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

That's interesting. I wonder what the perceived advantage of using circular
over linear polarisation is ?

Perception is everything, except in this case.

There are some technical advantages to CP. With a single LNB, it's
possible to install the dish with only elevation and azimuth, and no
consideration for tilt. However, with 2 or more LNB's, it is
necessary to align the dish tilt along the ecliptic.

US DTV HD dishes are now tilted but I don't recall this in the
beginning of their HD offering. Single/dual LNB are not tilted, at
least mine isn't and there is no aiming spec for it. US DISH network
has always tilted even with one LNB IIRC.


<snip>

 

[Arfa Daily]

"Nigel Feltham" <nigel.feltham@btinternet.com> wrote in message
news:HLadnQcuI-72Tf_XnZ2dnUVZ8hydnZ2d@brightview.co.uk...

Arfa Daily wrote:


"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:0cs3659cp4opu7ne8ntktnvtpvfcl1t79m@4ax.com...
On Sat, 18 Jul 2009 09:54:43 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

Circular polarisation for US DBS, Jeff ? Over this side of the pond,
it's
vertical and horizontal polarisation for alternate channels or whatever,
but
with the same selection / LNB powering voltages, and additional
switching
by
22kHz tone, the same.

DirecTV and Dish are both circular polarization.
HughesNet internet is linear (vertical or horizontal) polarization.
FTA (free to air) transmissions are all linear polarization.
Broadcast downlinks (FSS) are all linear polarization.

http://en.wikipedia.org/wiki/Low-noise_block_converter
"Most North American DBS signals use circular polarization, instead of
linear polarization, therefore requiring a different LNB type for
proper reception. In this case, the polarization must be adjusted
between clockwise and counterclockwise, rather than horizontal and
vertical."

This explains it in detail:

http://www.abadss.com/forum/102-faq-how/5880-understand-lnbs-standard-linear-circular-universal-lnb-lnbf-stacked.html



That's interesting. I wonder what the perceived advantage of using
circular over linear polarisation is ? I can see that polarisation twist
from passage of the signal through the atmosphere would be eliminated,
and
also skew caused by your E-W position with respect to the bird. Do you
think that's the reason ? I didn't realise that a c.p, LNB was
effectively
just an l.p LNB with a signal 'de-spinner' (lump of ferrite ?) in the
feed. As long as DBS has been going in Europe, which is quite a lot of
years now if you go back to the old analogue birds, c.p. has never been
used, which is why I'm not too familiar with it as applied to microwave
signals.

Not completely true - the UK's old BSB satellite service used circular
plolarisation (quoted as right hand circular which I'm assuming means
clockwise) until the system was killed off by SKY's dodgy dealings - they
persuaded the UK government that BSB would need 2 satellites so there
would
be a backup and that they'd need to use the more expensive D-MAC standard
to get good enough picture quality.

The result being it cost a fortune to get new box hardware designed and
put
2 satellites up just to broadcast 5 channels (which couldn't be expanded
without launching another 2 satellites) when at the same time SKY were
exempt from UK satellite broadcast restrictions due to uplinking from
Luxembourg and were allowed to rent space on an Astra satellite with space
for 16 channels and using cheaper PAL receivers that were already designed
and available.

When BSB closed down (after only 6 months of broadcasting) the 2
satellites
were sold to Scandinavian broadcasters who switched to D2-MAC and used
them
until 2003.

Yes, all quite true. I'd forgotten about the BSB service, it's active life
being so short ...

And to Jeff. The 'multi' LNBs that I was asking you about are not multiple
singles on a bracket on one dish, but all inside one standard sized LNB
package, so it's one lump with either two or four F connectors on its back.

Arfa

 

[Arfa Daily]

"mm" <NOPSAMmm2005@bigfoot.com> wrote in message
news:h4a5651t25pagovtedb6gpo674cd7epla4@4ax.com...

On Sat, 18 Jul 2009 17:58:10 -0500, AZ Nomad
aznomad.3@PremoveOBthisOX.COM> wrote:

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com> wrote:
What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It

Dishes are passive devices; they are not powered by anything but incoming
RF
energy.

Items sold as dishes include amplifers.

A good start would be to learn the difference between a dish,
LNB, and receiver.

A good start on what?

I'm not really interested in an electronics lesson. I just want to
know what voltage would power the amplifier on the VHF/UHF antenna
that surrounds the dish. The manual says it uses the same voltage
that dish does, or something like that. Maybe you can write the
manual's author.

I'll go with one of the helpful answers.

In order to get helpful answers, you first need to have a little respect for
the people who are trying to guide you. Your question doesn't even relate to
any kind of "repair" - read the name of the group, so you are doing well to
elicit any kind of sensible responses at all. If you are not interested in
learning in order to help yourself to arrive at answers, why should we waste
our time doing your research for you ? I would suggest that you try 110v AC
"or something like that". If it works, you won't need to ask any more, and
if it doesn't, you may learn a valuable lesson in both electronics, and life
....

Arfa

 

[Jeff Liebermann]

On Sun, 19 Jul 2009 10:13:03 -0400, Meat Plow <meat@petitmorte.net>
wrote:

On Sat, 18 Jul 2009 19:56:09 -0700, Jeff Liebermann
jeffl@cruzio.com>wrote:

On Sun, 19 Jul 2009 01:39:38 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

That's interesting. I wonder what the perceived advantage of using circular
over linear polarisation is ?

Perception is everything, except in this case.

There are some technical advantages to CP. With a single LNB, it's
possible to install the dish with only elevation and azimuth, and no
consideration for tilt. However, with 2 or more LNB's, it is
necessary to align the dish tilt along the ecliptic.

US DTV HD dishes are now tilted but I don't recall this in the
beginning of their HD offering. Single/dual LNB are not tilted, at
least mine isn't and there is no aiming spec for it. US DISH network
has always tilted even with one LNB IIRC.

Dual LNB is a single LNB with two front end sections. It is aimed at
a single satellite and can feed two receivers, or a dual front end
receiver (i.e. DVR). A dish with two seperate LNB's, each with 2
outputs or 1 output going to a DISEqC switch, is a different animal as
it's designed to hear two satellites. I try to avoid using the term
dual LNB because it's ambiguous.

I've installed a few single LNB dishes. The dish alignment
instructions and web pages didn't have any provisions for tilt. Only
when multiple LNB dishes appeared was there any consideration for
tilt. It might also be useful to note that the single LNB dishes do
not have any mechanism for adjusting tilt.

With HD, one must see more than one satellite. As usual, Europe does
it with a mechanical DISEqC protocol rotator, while the US does it
with multiple LNB's. Each has their benefits and problems. I wasn't
paying much attention when HD first appeared, but I do recall that it
required a new dish because the feed came from a different bird.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Sun, 19 Jul 2009 15:42:34 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

And to Jeff. The 'multi' LNBs that I was asking you about are not multiple
singles on a bracket on one dish, but all inside one standard sized LNB
package, so it's one lump with either two or four F connectors on its back.

See my comment to Mr Meat Plow about the ambiguous term "dual LNB".

There are dishes with 5 LNB's and a built in switch. For example, the
DirecTV AU9 Slimline dish:
<http://www.sadoun.com/Sat/Products/Winegard/DIRECTV-AU9-SLIMLINE-Ku-Ka-Dish.htm>
They have 4 outputs, each of which can be switched to one LNB and
pickup a satellite. The assumption is that there will be a maximum of
4 receivers attached, so that there's no need for a 5th output.

I haven't noticed a 5 LNB dish with only 2 outputs.

Things get rather messy with 7 satellites and 4 receivers:
<http://www.satpro.tv/ProductImages/wb68instalation22.gif>


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[mm]

On Sun, 19 Jul 2009 15:49:48 +0100, "Arfa Daily"
<arfa.daily@ntlworld.com> wrote:

"mm" <NOPSAMmm2005@bigfoot.com> wrote in message
news:h4a5651t25pagovtedb6gpo674cd7epla4@4ax.com...
On Sat, 18 Jul 2009 17:58:10 -0500, AZ Nomad
aznomad.3@PremoveOBthisOX.COM> wrote:

On Fri, 17 Jul 2009 18:27:05 -0400, mm <NOPSAMmm2005@bigfoot.com> wrote:
What voltage is meant to be used by 18 inch satellite dishes?

AC or DC?

I found a satellite antenna in the trash, and I dont have satellite,
but I saved the clip-on VHF/UHF antenna that goes around the edge. It

Dishes are passive devices; they are not powered by anything but incoming
RF
energy.

Items sold as dishes include amplifers.

A good start would be to learn the difference between a dish,
LNB, and receiver.

A good start on what?

I'm not really interested in an electronics lesson. I just want to
know what voltage would power the amplifier on the VHF/UHF antenna
that surrounds the dish. The manual says it uses the same voltage
that dish does, or something like that. Maybe you can write the
manual's author.

I'll go with one of the helpful answers.

In order to get helpful answers, you first need to have a little respect for
the people who are trying to guide you.

I have great respect for and gratitude to the people who are trying to
help or guide me. I don't believe the previous poster was.

OTOH, two posters gave me helpful answers. One was simple, and much of
the other was above me, but it was still quite helpful. Thank you,
both.

Your question doesn't even relate to
any kind of "repair" - read the name of the group, so you are doing well to
elicit any kind of sensible responses at all. If you are not interested in
learning in order to help yourself to arrive at answers, why should we waste
our time doing your research for you ? I would suggest that you try 110v AC
"or something like that".

I don't remember how the manual phrased it, but it said it used the
OTA antenna, that is the amplifier, used the same voltage as the dish,
an 18 inch dish used either for Dish network or Direct TV, probably
the first one.

If it works, you won't need to ask any more, and
if it doesn't, you may learn a valuable lesson in both electronics, and life

I already know that lesson, and I didn't have to burn anything out to
learn it.

...

Arfa

 

[Meat Plow]

On Sun, 19 Jul 2009 08:36:03 -0700, Jeff Liebermann
<jeffl@cruzio.com>wrote:

On Sun, 19 Jul 2009 10:13:03 -0400, Meat Plow <meat@petitmorte.net
wrote:

On Sat, 18 Jul 2009 19:56:09 -0700, Jeff Liebermann
jeffl@cruzio.com>wrote:

On Sun, 19 Jul 2009 01:39:38 +0100, "Arfa Daily"
arfa.daily@ntlworld.com> wrote:

That's interesting. I wonder what the perceived advantage of using circular
over linear polarisation is ?

Perception is everything, except in this case.

There are some technical advantages to CP. With a single LNB, it's
possible to install the dish with only elevation and azimuth, and no
consideration for tilt. However, with 2 or more LNB's, it is
necessary to align the dish tilt along the ecliptic.

US DTV HD dishes are now tilted but I don't recall this in the
beginning of their HD offering. Single/dual LNB are not tilted, at
least mine isn't and there is no aiming spec for it. US DISH network
has always tilted even with one LNB IIRC.

Dual LNB is a single LNB with two front end sections. It is aimed at
a single satellite and can feed two receivers, or a dual front end
receiver (i.e. DVR). A dish with two seperate LNB's, each with 2
outputs or 1 output going to a DISEqC switch, is a different animal as
it's designed to hear two satellites. I try to avoid using the term
dual LNB because it's ambiguous.

I've installed a few single LNB dishes. The dish alignment
instructions and web pages didn't have any provisions for tilt. Only
when multiple LNB dishes appeared was there any consideration for
tilt. It might also be useful to note that the single LNB dishes do
not have any mechanism for adjusting tilt.

With HD, one must see more than one satellite. As usual, Europe does
it with a mechanical DISEqC protocol rotator, while the US does it
with multiple LNB's. Each has their benefits and problems. I wasn't
paying much attention when HD first appeared, but I do recall that it
required a new dish because the feed came from a different bird.

Thanks for the explanation Jeff. I thought a dual LNB was actually two
LNBs with different polarizations. But as far back as I was paying
attention, the DISH discs were always tilted even before they offered
HD and it's always been a question floating around inside my head as
to why DTV were not tilted and DISH were way before HD. Maybe DISH has
two LNB devices anyway and looks at two different birds? Or is it
linier vs polarization circular at issue?

 

[Meat Plow]

On Sun, 19 Jul 2009 22:12:45 -0400, mm
<NOPSAMmm2005@bigfoot.com>wrote:

I already know that lesson, and I didn't have to burn anything out to
learn it.

Your free antenna was designed to use the Sat feedline to not only
power it but to also transfer the broadcast signal to either a Multi
Switch with an antenna output or a splitter provided by the antenna
manufacturer. My old Multi Switch had an antenna output IIRC. This
would block standard brodcast frequencies with the downlink, control
signals and voltages from your set.

If you just have the antenna itself and nothing else you may not have
enough of it to work. What brand/model is it?