6 Foot Solid Prime Focus Ku Conversion

[fred555]

I have a 6 foot Solid Prime Focus dish I'm thinking about converting to Ku.

Ku LNBF Requirements:
At least dual output.
Linear
Standard

So far this is what I have come up with:

Invacom QPF-031 (4 output: 2 Circular/2 Linear)

Mated to:


Invacom ADF-120

But I cannot find either of them in stock.

I also have one of these on order (circular only) from here in hopes of using the scalar section mated to a linear dual output lnbf in some sort of Frankenstein configuration:
http://multicomstore.com/products/r...eguide-prime-focus-antenna-free-shipping.html



Anybody have any other ideas on how to accomplish this given my requirements?

 

[Magic Static]

I would use a KU orthomode feed and a pair of Norsat LNBs and hook them up with a multi-switch, ie 3x4. But for big bucks I've seen the QPF-031 for sale on European sites. I want a QPF-031 also, but not for that kind of money

 

[fred555]

I would use a KU orthomode feed and a pair of Norsat LNBs and hook them up with a multi-switch, ie 3x4. But for big bucks I've seen the QPF-031 for sale on European sites. I want a QPF-031 also, but not for that kind of money

Could you post a link to the proper orthomode feed I would need to mount dual Ku Norsats?

Maybe this one?
http://gotcband.com/collections/feedhorns/products/chaparral-dual-feed

What is a good source for the Norsats? Any particular model number?

 

[Magic Static]

Could you post a link to the proper orthomode feed I would need to mount dual Ku Norsats?

Maybe this one?
http://gotcband.com/collections/feedhorns/products/chaparral-dual-feed

What is a good source for the Norsats? Any particular model number?

That's a C-Band unit.
I can't seem to find a ku one at the moment. I see them on Ebay frequently.
The other stuff you were looking for btw
https://satboy.com/index.php?k=43

 

[fred555]

That's a C-Band unit.
I can't seem to find a ku one at the moment. I see them on Ebay frequently.
The other stuff you were looking for btw
https://satboy.com/index.php?k=43

Thanks for the link!

 

[fred555]

This option may be cheaper than 2 Norsats and a Ku feed?


Quantity Price per unit Merchandise value
Invacom Flansch Quad Polar QPF-031

• Manufacturer: Invacom

1
79,75 EUR

Invacom Adjustable feed horn ADF-120

• Manufacturer: Invacom

1
20,92 EUR

Credit Card
1
4,88 EUR

DHL/Deutsche Post Weltpaket Premium1
35,00 EUR

Total sum 140,56 EUR

 

[Magic Static]

Considering a Euro is $1.08 right now, not too bad An ortho would probably perform better but will be more expensive.

 

[fred555]

Considering a Euro is $1.08 right now, not too bad An ortho would probably perform better but will be more expensive.

It sure does look like a good time to order from Europe:

Euro to US Dollar Rate

I may also order a usb tuner from them for the Pi2 project depending on what Updatelee recommends for his software he is adapting for the Pi2. But I do still want to price out the entire Ortho assembly first.
Please send any more links you may have in that regard.
I did find these EL Cheapos
http://multicomstore.com/dsu-ku-lnb-lnb-ku-12-2-ghz.html

I have never ordered from Europe, how long does delivery usually take?

I do have the prime focus circular Ku lnbf on the way to try to adapt to a linear until then.

 

[Lone Gunman]

iirc not too long ago that those Invacoms were advertised on fleabay for around $70 cuz I too have a 6' solid prime focus I was thinking of setting up for Ku only back a few years ago? Now there's only bulk purchase of 10 at $82 each = $810.

Looks like our supply of some cheap replacement parts is dwindling, especially since WSI went belly up from the DMS lawsuit. Funny, DMS sued WSI over the DMX741 copy of their BSC621 then after they won they stopped producing theirs and there are none to be found now??? WTF??

 

[fred555]

Now there's only bulk purchase of 10 at $82 each = $810.

I saw that too.

I am also thinking if there is a part there is a chance I may ever need in the future, buy it now while it still can be found.

 

[Titanium]

WSI didn't go out of business due to any lawsuit. Yes, there were some deceptive practices that were stopped several years before the business closed, but only addressed the product naming practices, not hardware design.

Bad business decisions, high overhead with two locations, poor customer support, too many substandard equipment builds, cloning/back-dooring competitors equipment and cut-throat pricing.... all added up to locking the doors and walking away.

No need to blame another business for what WSI did themselves.

I worked with Invacom to develop the QPH-031 and QPF-031 in 2004/2005. At that time single satellite DBS/DSS reception was supported by the subscription service providers. Initially they were developed to support FSS and DSS services from the same orbital slot and we're going to market DirecTV and AMC4 FTA faith-based channels as a package.

These LNBFs haven't been manufactured for many, many, many years and the market has been supported by NOS (New Old Stock) reserves. They only have use in the North America market and very few resellers stock a product that sells a few units each year. Yes, buy them while you can, as it is highly unlikely that you will ever see this type of combo LNBF again and in such high quality build!

 

[Lone Gunman]

I had no problems with WSI products nor with support that I got from Robbie on the one item that I had a problem with, ie, the NS741S that I bought. It turned out that the box was mislabeled and what I was sent was an NS741U instead. When he finally found out what had happened, he sent me an NS741S free of charge and just told me to keep the U that was sent by mistake, which I still have today.

But back to DMS, as I said, it seems to me that once they won the lawsuit they basically discontinued the BSC621S so neither it nor the WSI clones are available now.

I originally went with the DMX741 because I wanted to get rid of the servo motor and the Corotor II I was using at the time because I didn't want to keep the GI920 I had up and running just to move the dish and change polarity for the AZBox Elite that was slaved to it. That DMX741 and the Vbox X that I bought cost me less than $80 shipped and allowed me to park that GI920 on the shelf and use the Elite to move the dish and change the polarity. I expect truth be known the electricity saved the first year from that unplugged 920 actually paid for the conversion to the DMX and the Vbox.

So now we're back to Corotors with 2 LNBs and a servo and the only way to operate them now is either with an old receiver hooked up with a modern receiver slaved to it....again, OR, purchase an ASC-1 @ what, $150? to do what a $35 Vbox had previously done.

So I'm just saying that in my relatively short experience with FTA equipment it seems the evolution has gone from bad to much better to bad again where equipment cost is concerned and cost is the one thing that just might drive me away from the hobby just like the expense of racing is forcing me to sell my race car.

Just my $.02 worth! And your mileage may vary!

 

[Titanium]

DMSI Lawsuit? Nope... as supported by this post by WSI: http://www.satelliteguys.us/xen/posts/3110891/

Guess we also forgot what was not happening when WSI was released as a site sponsor? Customer and product support?

Back onto subject: Optimized solutions for KU reception on a prime focus dish? I agree with Magic Static. An orthomode feed and a pair of quality Norsat LNBs is the best option for optimal performance. The Invacom adjustable scalar paired with the Inverto Black C120 LNB would be a great LNBF option. Both readily available and not too expensive - $40. If the op doesnt want to spend too much $$$, how about the GEOSATpro SL1P for $18?

 

[Magic Static]

I have never ordered from Europe, how long does delivery usually take?

I've ordered from several places in Europe and it isn't too bad. I get stuff from China quick too. These "World Wide Shipping" companies really do

 

[Titanium]

I have never ordered from Europe, how long does delivery usually take?

Some items arrive within the week. Other shippers have taken 3 weeks. Just received a USB ATSC dongle that took more than three weeks...

 

[fred555]

how about the GEOSATpro SL1P for $18?

I have a requirement of dual output to feed many receivers from powered multiswitches.
I will check out the Inverto Black C120 LNB, thanks for the suggestion.

 

[fred555]

Frankenstein Option

Here is donor number one:

Prime focus dual circular

Donor number two:

Dual output linear


Here are both disassembled:

So it looks promising. Press the scalar assembly off of the prime focus on the left,
cut off the linear on the right where the circular is cut, then press the scalar assembly onto the linear.
I must stuff something soft down the neck of the linear to prevent metal shavings contamination.

 

[fred555]

how about the GEOSATpro SL1P for $18?

That is probably a good idea, I can use the SL1P in a comparison study with the Frankenstein model above.
If the Frankenstein is close I will use it, but if the signal levels are extremely subpar, I will be placing an order from Europe.
(A good chance I will order from Europe either way just to have parts.)

 

[polgyver]

I am just curious, what Quality you could get, if you use SL2PLL LNBF? This is LNBF for offset dishes, but, maybe it could deliver acceptable "Q" ?
I do not know your 6' dish's focal length. Sadoun 180 cm dish has 682 mm focal length. Channel Master 120 cm offset dish has F=725 mm.
Ariza 120 cm has F=720 mm. Therefore, your prime focus 6' dish could be considered equivalent to 100-105 cm offset dish (which is rather decent size...). Of course, such offset LNBF would "see" only central part of your prime focus dish, but, the less visible "outside ring" can also be useful by blocking warm Earth's thermal noise.
Is this dish motorized, or, designated to just one satellite?
Cheers, polgyver

 

[fred555]

I am just curious, what Quality you could get, if you use SL2PLL LNBF?

I was thinking about that too. I don't have any spare SL2PLLs, so I think I will order another one.

Is this dish motorized, or, designated to just one satellite?

It will be stationary for now. I have one actuator that will go on my 10 footer, maybe if my multi lnbf setup does not pan out. With all my dishes shared to many TVs, motors are not a good fit. I like having a dish per or lnbf per favorite satellite. Imagine my wife is watching something in one room and I was to move the dish to watch something else in another room, not good.

FTA and OTA are the only TV source I have. Luckily I don't need a rotor on my antenna either. My Antenna points to one major market and I pick up the only other market in the opposite direction off the backside. Channel changes are quick this way too, no lag waiting for a reposition, with FTA or OTA. I like to surf a while before settling on a channel, no EPG is no problem.