Converting dss lnbf's to receive ku

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Just wondering if anyone besides me has tried to do it. Increasing amounts
of small dish hardware by the dumpsters these days, begging for creative
sacrificial experimentation.

-lurk
 
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On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
<lakerror1shmi@wolferror2mark.com> wrote:

>
>Just wondering if anyone besides me has tried to do it. Increasing amounts
>of small dish hardware by the dumpsters these days, begging for creative
>sacrificial experimentation.
>
>-lurk
>
>

Don't bother.
 

m0nkey

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"lurknowhere" <lakerror1shmi@wolferror2mark.com> wrote in message
news:ZUQMc.79$nq4.75@fe07.usenetserver.com...
>
> Just wondering if anyone besides me has tried to do it. Increasing
amounts
> of small dish hardware by the dumpsters these days, begging for creative
> sacrificial experimentation.
>
> -lurk


not possible
 
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On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
<lakerror1shmi@wolferror2mark.com> wrote:

>
>Just wondering if anyone besides me has tried to do it. Increasing amounts
>of small dish hardware by the dumpsters these days, begging for creative
>sacrificial experimentation.


You will require a nice spectrum analyzer and some experience in
microwave RF engineering.
 
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Right frequency, wrong polarization. They're circular,
and you want linear.

-Web

In article <733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com>, kryppy@.
says...
> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> <lakerror1shmi@wolferror2mark.com> wrote:
>
> >
> >Just wondering if anyone besides me has tried to do it. Increasing amounts
> >of small dish hardware by the dumpsters these days, begging for creative
> >sacrificial experimentation.
>
>
> You will require a nice spectrum analyzer and some experience in
> microwave RF engineering.
>
>
>
 
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"Web Williams" <Doncha@WishuKnew.com> wrote in message
news:MPG.1b6f85c1c18dfae989abf@news.usenetserver.com...
> Right frequency, wrong polarization. They're circular,
> and you want linear.
>
> -Web
>
> In article <733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com>, kryppy@.
> says...
> > On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> > <lakerror1shmi@wolferror2mark.com> wrote:
> >
> > >
> > >Just wondering if anyone besides me has tried to do it. Increasing
amounts
> > >of small dish hardware by the dumpsters these days, begging for
creative
> > >sacrificial experimentation.
> >
> >
> > You will require a nice spectrum analyzer and some experience in
> > microwave RF engineering.
> >

Well, I did build (component level) and successfully operate my first C-band
receive only earth station system in 1983 (120 degree lna, receiver and all
metal dish). I'm still using the 12.5 foot square spherical reflector after
all these years. Even without the specialized equipment excellent results
can be obtained. All that's required is sufficient ingenuity, creativity,
and a reason to use it. I'm seldom stumpted due to a lack of either one.
For me, it's not just about watching tv from a distance with a remote in
hand.

-Dan
 
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"m0nkey" <allah@achtung.com> wrote in message
news:2mj66gFnjr43U1@uni-berlin.de...
> "lurknowhere" <lakerror1shmi@wolferror2mark.com> wrote in message
> news:ZUQMc.79$nq4.75@fe07.usenetserver.com...
> >
> > Just wondering if anyone besides me has tried to do it. Increasing
> amounts
> > of small dish hardware by the dumpsters these days, begging for creative
> > sacrificial experimentation.
> >
> > -lurk
>
>
> not possible
>
>

Wrong.
 
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"Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
news:52j8g0p72lm859t18headuh920q18121o3@4ax.com...
> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> <lakerror1shmi@wolferror2mark.com> wrote:
>
> >
> >Just wondering if anyone besides me has tried to do it. Increasing
amounts
> >of small dish hardware by the dumpsters these days, begging for creative
> >sacrificial experimentation.
> >
> >-lurk
> >
> >
>
> Don't bother.


Why would I bother? Because I enjoy experimenting modifying and pursuing
alternatives for the fun of it. I'm an outlaw in a rigid conformist world
of preassembled predictability.
Watching this hobby develop over the years into a plug and play no brainer
adventure has not diminished the challenge at all. A different level of
experimentation always exists for exploring minds with excess raw materials.
I'm not an engineer, but I've logged many years of self taught technical
experience in electronics, having owned and operated a servicing business
that evolved from a hobby that wouldn't stop. One thing I noticed about most
all school trained techs applying to work for me was that they couldn't
function well without schematic diagrams. I didn't have that problem. I'm
retired from the business now due to other interests and a consumer repair
market that collapsed. Downsized to a hobby, I'm back where all the fun
began, recycling used equipment for projects that expand my capabilities,
and interests. The true spirit of experimentation has more to do with the
process than the result. It's amazing what can happen during the creative
adventure of what to others may appear rather meaningless. I love the
bother, and I'm an artist, so it's a hopeless crusade for the sake of
expression. A hobby cannot be passive without a dull unbothered mind that
learns few things anew.

you asked...

-Dan
 
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"kryppy" <kryppy@.> wrote in message
news:733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com...
> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> <lakerror1shmi@wolferror2mark.com> wrote:
>
> >
> >Just wondering if anyone besides me has tried to do it. Increasing
amounts
> >of small dish hardware by the dumpsters these days, begging for creative
> >sacrificial experimentation.
>
>
> You will require a nice spectrum analyzer and some experience in
> microwave RF engineering.
>
>

Well, I did build (component level) and successfully operate my first C-band
receive only earth station system in 1983 (120 degree lna, receiver and all
metal dish). I'm still using the 12.5 foot square spherical reflector after
all these years. Even without the specialized equipment excellent results
can be obtained. All that's required is sufficient ingenuity, creativity,
and a reason to use it. I'm seldom stumpted due to a lack of either one.
For me, it's not just about watching tv from a distance with a remote in
hand.

-Dan
 
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"kryppy" <kryppy@.> wrote in message
news:733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com...
> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> <lakerror1shmi@wolferror2mark.com> wrote:
>
> >
> >Just wondering if anyone besides me has tried to do it. Increasing
amounts
> >of small dish hardware by the dumpsters these days, begging for creative
> >sacrificial experimentation.
>
>
> You will require a nice spectrum analyzer and some experience in
> microwave RF engineering.
>
>

I like to experiment modifying and pursuing alternatives for the fun of it.
Watching this hobby develop over the years into a plug and play no brainer
adventure has not diminished the challenge at all. A different level of
experimentation always exists for exploring minds with excess raw materials.
I'm not an engineer, but I have many years of technical experience in
electronics servicing, having owned and operated a business that evolved
from a hobby that wouldn't stop. One thing I noticed about most all school
trained techs applying to work for me was that they couldn't function well
without schematic diagrams. I didn't have that problem. I'm now retired
from the business due to other interests and a consumer repair market that
collapsed. Downsized to a hobby, I'm back where all the fun began,
recycling used equipment for projects that expand my capabilities. The true
spirit of experimentation has more to do with process than result. It's
surprising what can be accomplished despite the apparent lack of 'tools'.
I'm testing the audience here for different specifics.

-Dan
 
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You top posted and I mistakenly replied to the lower portion of the thread
in my first message. In regard to your advice about the incompatibility of
polarization, I have solved that delemma. In fact it was the easier part of
the conversion. I merely removed the plastic cover and pulled the thin
teflon insert from the feedhorn throat. The rest of the process was just
about as easy without using any specialized equipment or tools. It was
something I've never heard done. So I had to try, despite being talked down
by those who never did.

-Dan



"Web Williams" <Doncha@WishuKnew.com> wrote in message
news:MPG.1b6f85c1c18dfae989abf@news.usenetserver.com...
> Right frequency, wrong polarization. They're circular,
> and you want linear.
>
> -Web
>
> In article <733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com>, kryppy@.
> says...
> > On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
> > <lakerror1shmi@wolferror2mark.com> wrote:
> >
> > >
> > >Just wondering if anyone besides me has tried to do it. Increasing
amounts
> > >of small dish hardware by the dumpsters these days, begging for
creative
> > >sacrificial experimentation.
> >
> >
> > You will require a nice spectrum analyzer and some experience in
> > microwave RF engineering.
> >
> >
> >
>
 
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On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
<Doncha@WishuKnew.com> wrote:

>Right frequency, wrong polarization. They're circular,
>and you want linear.
>
>-Web

The polarisation is the easy part. Just yank out the dielectric plate
or the wedge. The frequency 550 Mhz higher for DBS, so it will take
some work to bring that down.
 

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Why do you need to drop the LO frequency? Adjust your receiver's LNB setup
to reflect the LO freq. of your choice.
-------------------
Brian Gohl
Satellite Audio Video
http://www.adventistsat.com


"Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
news:vjsdg09e7snpest3lak60d0nksm8m7rugf@4ax.com...
> On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
> <Doncha@WishuKnew.com> wrote:
>
> >Right frequency, wrong polarization. They're circular,
> >and you want linear.
> >
> >-Web
>
> The polarisation is the easy part. Just yank out the dielectric plate
> or the wedge. The frequency 550 Mhz higher for DBS, so it will take
> some work to bring that down.
 
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The only problem might be that the whole microwave circuit may be designed
specifically for the DSS region right down the line capacitors and wave
guide and there may not be enough leeway to change it.

I'll forget when I saw a micorowave device in the 1990 ARRL Handbook
(purchased it after getting my ham license),not knowing anything about
microwave stuff,I was amazed to discover that some componenents,capacitors I
think,or was it resistors were just a strip of copper on the pcb!

Seems easier to just buy a used ku lnb(f) off of Ebay!

"Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
news:vjsdg09e7snpest3lak60d0nksm8m7rugf@4ax.com...
> On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
> <Doncha@WishuKnew.com> wrote:
>
> >Right frequency, wrong polarization. They're circular,
> >and you want linear.
> >
> >-Web
>
> The polarisation is the easy part. Just yank out the dielectric plate
> or the wedge. The frequency 550 Mhz higher for DBS, so it will take
> some work to bring that down.


---
Outgoing mail is certified Virus Free.
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"Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
news:vjsdg09e7snpest3lak60d0nksm8m7rugf@4ax.com...
> On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
> <Doncha@WishuKnew.com> wrote:
>
> >Right frequency, wrong polarization. They're circular,
> >and you want linear.
> >
> >-Web
>
> The polarisation is the easy part. Just yank out the dielectric plate
> or the wedge. The frequency 550 Mhz higher for DBS, so it will take
> some work to bring that down.


I believe the Ku10750 LO is spaced 500Mhz lower than the DBS/DSS 11250 LO.

It's possible to do a partial band conversion without much effort. The lnbf
(DSS) I choose for the experiment had a metal back plate held in place by
screws. Once inside I retuned the DRO by adjusting the LO set-screw. There
was sufficient range to allow me to lower the LO frequency by over 250 Mhz..
I choose 208Mhz because it provided the highest reading on my IF signal
testing meter connected inline at the lnbf. Further lowering the LO brought
more transponders into the 950 -1450 window, but at a sacrifice of IF signal
level and decreased quality overall. So 208Mhz was optimum without
modifying any RF circuitry. Six transponders (offset by 208Mhz) were
located on a blind search. The polarity was found to be reversed with the
lnbf mounted normally -- turning it 90 degrees would solve that problem.
Keep in mind that I am receiving Americas (Telstar) 5 transmissions using a
21-22" Dishnet 500 dish, significantly smaller than a standard 1 meter Ku
dish. Here are my results from west central Wisconsin on a clear day:

Tr27 12177 V--12385 H Mhz--quality 35% locked
Tr26 12152 H--12359 V Mhz--quality 20% locked
Tr25 12144 V--12353 H Mhz--marginal
Tr24 12122 H--12330 V Mhz--"
Tr23 12115 V--12322 H Mhz--"

Obviously the signal would be well in the green using a larger dish designed
for Ku reception. But this test proved it's possible to easily modify (5
minutes) an DBS lnbf to test KU reception on a small DBS dish with very
little work and no special tools. Of course, without a spectrum analyzer or
frequency counter, the blind search function made it quick and simple to
locate unknown shifted transponder IF frequencies. Also, it should be noted
that 15% of the lnbf scaler ring is missing due to another experiment in the
past where a modification was needed to fix a co-feed spacing problem. I
was using co-feeding 5 lnbf's on a Primestar dish where two adjacent
satellites were only 4 degrees apart. Some scaler had to be trimmed. DSS
lnbf''s don't fully illuminate the horizontally oval Primestar dish surface
anyway, so precision numbers don't really apply here. In the end it all
worked fine. Reinstalling the lnbf (with some of the scaler ring missing)
on it's original matching DSS offset dish probably diminished the gain due
to a distortion in the feed to dish illumination, but again, in the end it
worked surprisingly well - even with an added handicap.


-Dan
 
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The LO of the lnbf determines the downconverted block range of IF
frequencies that correspond to the transponders. If the LO is too high (or
too low) the IF block will exceed the limits of the bandpass filter within
the lnbf. Trying to align the receiver to the LO of your choice will not
change the fact that the receiver cannot process an out of band attenuated
IF frequency block. No transponders will be found.

-Dan

"Brian" <b.gohl@comcast.net> wrote in message
news:nNSdnZORR_Fka5vcRVn-jw@comcast.com...
> Why do you need to drop the LO frequency? Adjust your receiver's LNB setup
> to reflect the LO freq. of your choice.
> -------------------
> Brian Gohl
> Satellite Audio Video
> http://www.adventistsat.com
>
>
> "Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
> news:vjsdg09e7snpest3lak60d0nksm8m7rugf@4ax.com...
> > On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
> > <Doncha@WishuKnew.com> wrote:
> >
> > >Right frequency, wrong polarization. They're circular,
> > >and you want linear.
> > >
> > >-Web
> >
> > The polarisation is the easy part. Just yank out the dielectric plate
> > or the wedge. The frequency 550 Mhz higher for DBS, so it will take
> > some work to bring that down.
>
>
 
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"Valdivar" <rebelleader68@hotmail.com> wrote in message
news:pfNNc.14130$BU4.772741@news20.bellglobal.com...
> The only problem might be that the whole microwave circuit may be designed
> specifically for the DSS region right down the line capacitors and wave
> guide and there may not be enough leeway to change it.
>
> I'll forget when I saw a micorowave device in the 1990 ARRL Handbook
> (purchased it after getting my ham license),not knowing anything about
> microwave stuff,I was amazed to discover that some componenents,capacitors
I
> think,or was it resistors were just a strip of copper on the pcb!
Seems easier to just buy a used ku lnb(f) off of Ebay!


I obtained my first GASFET's from Hewlet Packard back in 1983; paid $100
each for three to build a 100 degree C-band lnb. The voltage controlled LO
module was another $125, plus teflon boards and various surface mount
components. I constructed the waveguide out of copperclad board. My lnb
soldered together in modules - very compact assembly. It took weeks to
solve a stability problem due to intermittent self-oscillation of the lna
stages. Those tiny striplines and ground planes are governed by pure magic.
But that was 20 years ago... Now one can buy a premade $15 ku lnbf off
Ebay -- but that's just too easy!

-Dan


>
> "Gary Tait" <classicsat@yahoo.cominvalid> wrote in message
> news:vjsdg09e7snpest3lak60d0nksm8m7rugf@4ax.com...
> > On Mon, 26 Jul 2004 22:19:38 -0400, Web Williams
> > <Doncha@WishuKnew.com> wrote:
> >
> > >Right frequency, wrong polarization. They're circular,
> > >and you want linear.
> > >
> > >-Web
> >
> > The polarisation is the easy part. Just yank out the dielectric plate
> > or the wedge. The frequency 550 Mhz higher for DBS, so it will take
> > some work to bring that down.
>
>
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.706 / Virus Database: 462 - Release Date: 6/14/2004
>
>
 
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On Tue, 27 Jul 2004 08:27:57 -0500, "lurknowhere" <fixlakshmi@wolfmark.com>
wrote:

>
>"kryppy" <kryppy@.> wrote in message
>news:733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com...
>> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
>> <lakerror1shmi@wolferror2mark.com> wrote:
>>
>> >
>> >Just wondering if anyone besides me has tried to do it. Increasing
>amounts
>> >of small dish hardware by the dumpsters these days, begging for creative
>> >sacrificial experimentation.
>>
>>
>> You will require a nice spectrum analyzer and some experience in
>> microwave RF engineering.
>>
>>
>
>Well, I did build (component level) and successfully operate my first C-band
>receive only earth station system in 1983 (120 degree lna, receiver and all
>metal dish). I'm still using the 12.5 foot square spherical reflector after
>all these years. Even without the specialized equipment excellent results
>can be obtained. All that's required is sufficient ingenuity, creativity,
>and a reason to use it. I'm seldom stumpted due to a lack of either one.
>For me, it's not just about watching tv from a distance with a remote in
>hand.
>
>-Dan
>
>
good for you Dan. I remember those 12 foot
reflectors, never actually made one,
I believe they were made from redwood framing.
Built my first 1 transistor regen radio back in 1958, the germanium
transistor cost 10 pound sterling, about $100 in today's money.
It worked great for those times.
 
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On Tue, 27 Jul 2004 08:41:31 -0500, "lurknowhere"
<fixlakshmi@wolfmark.com> wrote:

>
>"kryppy" <kryppy@.> wrote in message
>news:733ag0lav4ic8qcpelpekjj7ofp5iqel4a@4ax.com...
>> On Sun, 25 Jul 2004 11:05:13 -0500, "lurknowhere"
>> <lakerror1shmi@wolferror2mark.com> wrote:
>>
>> >
>> >Just wondering if anyone besides me has tried to do it. Increasing
>amounts
>> >of small dish hardware by the dumpsters these days, begging for creative
>> >sacrificial experimentation.
>>
>>
>> You will require a nice spectrum analyzer and some experience in
>> microwave RF engineering.
>>
>>
>
>I like to experiment modifying and pursuing alternatives for the fun of it.
>Watching this hobby develop over the years into a plug and play no brainer
>adventure has not diminished the challenge at all. A different level of
>experimentation always exists for exploring minds with excess raw materials.
>I'm not an engineer, but I have many years of technical experience in
>electronics servicing, having owned and operated a business that evolved
>from a hobby that wouldn't stop. One thing I noticed about most all school
>trained techs applying to work for me was that they couldn't function well
>without schematic diagrams. I didn't have that problem. I'm now retired
>from the business due to other interests and a consumer repair market that
>collapsed. Downsized to a hobby, I'm back where all the fun began,
>recycling used equipment for projects that expand my capabilities. The true
>spirit of experimentation has more to do with process than result. It's
>surprising what can be accomplished despite the apparent lack of 'tools'.
>I'm testing the audience here for different specifics.
>


I can tell you it is a simple project for a properly trained and
equipped shop. I watched my buddy at HNS retune a DBS lnbf
in twenty minutes. Without the HP I honestly can't see it being done,
but I would really enjoy reading your HOW-TO for the home LNBF
retuner.

Heres my contribution to your project.
http://www.qsl.net/g0ory/10g/sce975/sce975.html
http://www.geocities.com/ResearchTriangle/System/5140/10gig.html
 
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Archived from groups: alt.video.satellite.mpeg-dvb (More info?)

Well, yeah, you could do that, but with a BRAND NEW
Ku-band LNBF selling for around $10, why bother???
The labor of disassembling the case and pulling out
the teflon insert is worth more to me than that!
(At today's labor prices...)

-Web

P.S. I usually always top-post....

In article <o6tNc.163$zw3.158@fe07.usenetserver.com>,
fixlakshmi@wolfmark.com says...
> You top posted and I mistakenly replied to the lower portion of the thread
> in my first message. In regard to your advice about the incompatibility of
> polarization, I have solved that delemma. In fact it was the easier part of
> the conversion. I merely removed the plastic cover and pulled the thin
> teflon insert from the feedhorn throat. The rest of the process was just
> about as easy without using any specialized equipment or tools. It was
> something I've never heard done. So I had to try, despite being talked down
> by those who never did.
>
> -Dan