Just Sharing This Chaparral LNBF

[Satfaca]

Albeit having a dozen of C-band feedhorns on stash I couldn't resist taking another one off Ebay the other day.
It's the first LNBF made by Chaparral I've ever seen, it must have been from the early 90s or even late 80s, who knows. It is a diecast, very robust, I somehow "suspect" it is/was designed to work on both linear & circular polarity.
Since winter just started here, it won't be before next spring/summer when I eagerly try it out.

Anyone from the forum familiar with this thing?

 

[Channel Hopper]

Albeit having a dozen of C-band feedhorns on stash I couldn't resist taking another one off Ebay the other day.
It's the first LNBF made by Chaparral I've ever seen, it must have been from the early 90s or even late 80s, who knows. It is a diecast, very robust, I somehow "suspect" it is/was designed to work on both linear & circular polarity.
Since winter just started here, it won't be before next spring/summer when I eagerly try it out.

Anyone from the forum familiar with this thing?

View attachment 159370View attachment 159371View attachment 159372View attachment 159373View attachment 159374View attachment 159375

Not familiar at Cband, but the vane system was used on the very first LNB polariser system I had, around 1987/8, on an IRTE 1.5m dish.

Look after it well, the 60K noise might not be good for reception but it will be relatively true compared to todays fabricated figures.

Who knows, you could change the front end pin diodes and give it a new lease of life.

 

[John]

Albeit having a dozen of C-band feedhorns on stash I couldn't resist taking another one off Ebay the other day.
It's the first LNBF made by Chaparral I've ever seen, it must have been from the early 90s or even late 80s, who knows. It is a diecast, very robust, I somehow "suspect" it is/was designed to work on both linear & circular polarity.
Since winter just started here, it won't be before next spring/summer when I eagerly try it out.

Anyone from the forum familiar with this thing?

View attachment 159370View attachment 159371View attachment 159372View attachment 159373View attachment 159374View attachment 159375

Wow, never ever seen one of those before, what a great historical find. Look forward to your findings in the future .

 

[Joolz]

The only info I found about this product was this. It never seemed to make it onto the UK market at the time maybe as it was only for linear polarisation?

 

[John]

I must admit, to satisfy my curiousity, i wouldn't mind replicating one of those poloriser plates if i had the precise drawing information at hand

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

 

[Satfaca]

The only info I found about this product was this. It never seemed to make it onto the UK market at the time maybe as it was only for linear polarisation?

Superb find, Joolz!
Wonder what makes you confident it was linear only?

BTW, just found another piece here.

 

[Joolz]

Just a guess as I dont see a way you can fit a dielectric plate into the feedhorn and I see no mention of it in old UK dealer catalogues from that era.

 

[John]

Just a guess as I dont see a way you can fit a dielectric plate into the feedhorn and I see no mention of it in old UK dealer catalogues from that era.

I tend to go with your thinking Joolz - knowing the first and last missing word could help us

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

 

[Joolz]

This template came in many forms.

Polar axis

Hello members, a question ; is about the polar axis. wants to adjust the polar axis for the C-band. as you know I live in Aalten (the Netherlands). 7 degrees east (eutelsat 7) is the middle of the track for me. Which Satellite for the C-band do I need to properly adjust the polar axis...

rickcaylor.websitetoolbox.com

 

[Satfaca]

Just a guess as I dont see a way you can fit a dielectric plate into the feedhorn and I see no mention of it in old UK dealer catalogues from that era.

It's not a precondition to have a plate in order to transform circular signals to linear ... or better to cross divide the polarity, there are at least two other priniples (or patents) to do that.
I somehow feel that this cross in front (encircled in red) is from a dielectric material and its form could have a role, besides there are two steps seen in the depth (marked with red arrow) which definitely "brake" circular into linear (same thing as ADL CPOR feedhorns or well known Av-Comm tubes).



If I swiftly compare mine with the 2nd one mentioned above (Ebay), I'd say the last been missing the cross ... so it makes me think there have been linear and international/circular versions of this PolarAmp LNBF.



BTW Seavey had complete another solution with four dipoles...

 

[Satfaca]

I must admit, to satisfy my curiousity, i wouldn't mind replicating one of those poloriser plates if i had the precise drawing information at hand

I can do that with cutting off some carton board precisely copying the original and send it to you per snail mail... PM me if you want that.

 

[g host]

Hi.
Nice treasure.
Could you make some drawing with measurement, please ?
Maybe will be useful in future.

 

[John]

I can do that with cutting off some carton board precisely copying the original and send it to you per snail mail... PM me if you want that.

Thanks for the offer @Satfaca ..... i can see from one of the latest pictures how it's supposed to be used so my curriousity has been satisfied thank you.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

 

[satesco]

I had the same curiosity for this LNB, but in the 90s it was priced, as it is now, exorbitant for my budget. I bought it a few years ago, more for the fame it gained in those years.
I used it on my 1.50-meter dish, and the results aren't too impressive. This is due to my lnb clamping system, which I designed for a small antenna. On top of that, I also have a physical inconvenience, that is the antenna is suspended at a great height, which doesn't allow me to make adjustments to the LNB as I would like.
But even so, I did some tests with it in C-band. I'm not sure if I would get a better result if I had worked on a large antenna, at least 2m. But now, when the C-band is used between 3800-4200 MHZ, due to WIMAX interference and others, the scanning results are not like before cell phones.
And Chaparral is no exception when it captures the useful signal and noise at the same time. In areas with strong interferences, this lnb reacts the same way as those that are not protected (this is a way of saying, because even after 3800 MHZ some frequencies are affected).
After all, I use regular lnb and with the dielectric plate I have better results.
Here are some examples with Chaparral, and let's say, Galaxy Inn & Kaonsat (I can choose other lnb) at 40.0E.
Probably with newer versions of Chaparral one can get better results.
I'd like to be conflicted, but this lnb is not for the dxer looking to lock weak signals.

 

[Satfaca]

This is something not to be compared here ... as it looks you have a Chaparall Corotor II+ International feedhorn (that was the official name branded by Chapparal Communications back in the 90s).

 

[satesco]

This is something not to be compared here ... as it looks you have a Chaparall Corotor II+ International feedhorn (that was the official name branded by Chapparal Communications back in the 90s).

You're right, I should have mentioned that. My comment refers to this old model.
Having the latest Chaparral, I'm curious to see what results you get with it. This is of particular interest to me, but at the same time I'm still paying attention how the LNB is protected from interference.
I assume that the engineers at this company have found solutions and adapted the lnb to today's satellite transmissions,
I am waiting to see the tests with the new model, the one in the pictures you posted.

 

[scopus]

You're right, I should have mentioned that. My comment refers to this old model.
Having the latest Chaparral, I'm curious to see what results you get with it. This is of particular interest to me, but at the same time I'm still paying attention how the LNB is protected from interference.
I assume that the engineers at this company have found solutions and adapted the lnb to today's satellite transmissions,
I am waiting to see the tests with the new model, the one in the pictures you posted.

I don't think any engineers at Chaparral will be thinking about 5G. The company closed some time back, about 3 years ago I believe.

 

[Satfaca]

You're right, I should have mentioned that. My comment refers to this old model.
Having the latest Chaparral, I'm curious to see what results you get with it. This is of particular interest to me, but at the same time I'm still paying attention how the LNB is protected from interference.
I assume that the engineers at this company have found solutions and adapted the lnb to today's satellite transmissions,
I am waiting to see the tests with the new model, the one in the pictures you posted.

You must have misunderstood, the PolarAmp posted is from the 80s ... from the golden era of C-band satellite reception in the US. I bet that scientific development peaked at that time aswell and nothing produced/developed later could or have had surpassed the performance of feedhorns anytime later. LNB's are other story.
The original Chaparral Communications company somehow "died" in the late 90s with the transition from analog to digital satellite television and the evolvement of DirecTV & DISH Network.

I've just posted this because I find the model very rare, in fact in my 30+ years of "suffering" with the industry/hobby I've never ever seen any info
about its existance. I guess this forum now is the only source on the www naming it with the right name (thanks to @Joolz) - #PolarAmp.

BTW, there are many different C-band only and C/Ku corotor versions existing, partly due to sucessful ADL's patent challange against Chaparral which had to change the design of their products (just browse for Polarotor/Polarotor II/Corotor I/Corotor II/Corotor II+/TriBand).

 

[satesco]

Often, news comes from a misunderstanding, even if it's old, like the topic about this lnb.
I didn't know the company had disappeared. I bought it to check out what I wanted in the 90s. Seeing the results I got with my model, I'm no longer interested in Chaparral.
But it's good to find out what and how on this occasion.
Can someone, possibly you, still do tests with the example you posted since you opened the discussion about Chaparral, otherwise, welcome.

 

[Satfaca]

From my initial post above: "Since winter just started here, it won't be before next spring/summer when I eagerly try it out."