Invacom QWPH-031 weight issue solution

Status
Please reply by conversation.

freezy

SatelliteGuys Pro
Original poster
Apr 19, 2009
960
0
Land of Sky Blue Water
if this weighs so much could we just run a couple stainless fishing leaders from the lnb yoke to the edge of the dish and attach with a couple screws
ftaimages.jpg

img%5D
my.php
ftaimages.jpg
 
if this weighs so much could we just run a couple stainless fishing leaders from the lnb yoke to the edge of the dish and attach with a couple screws
ftaimages.jpg

img%5D
my.php
ftaimages.jpg

Freezy,

Yes you can, but don't attach them that high up on the dish as shown in your picture. The "struts" will interfere with your signal reception. Attach them down to the same degree positions on the lower portion of the dish, instead of up above. It will be perfect. Also, 1/2" aluminum tubing with the ends folded flat will do just fine, no need to use stainless unless you happen to have it freely available.

Using fishing leaders would not be a benefit as the LNBF support arm can "bounce" upwards just the same as it can sag or drift to the left or the right. You want to use something which is solid, not a flexible wire.

I would also like to add that with a Winegard DS-2076 dish (which does not have these side "struts") you can rob the struts used on the Winegard DS-3101 dish and simply drill two holes for the bolts in the perimeter of the dish to fit them on the DS-2076 dish.

This works really fine and gives the dish a really sturdy feel. However.... I have removed these struts from my DS-2076 and have been using it without them for over a year during all kinds of crazy winds and I have not experienced any problems what-so-ever. So, the weight of this LNBF is not as critical as some may think. As long as the dish is aligned properly, I don't think you will ever notice any trouble.

RADAR
 
Ahhh I see it so clear now.

Why don't they make a smaller/lighter dual LNB? I don't see an advantage on a motor setup at all.

Maybe on a fixed dish but then why would you need the circ./Linear capability?

What is available in the lower Ku "Universal" Ku band in the Western Hemisphere? If anything it would make more sense to put that in a LNB than doubling up on a dish that is moving around.
 
if this weighs so much could we just run a couple stainless fishing leaders from the lnb yoke to the edge of the dish and attach with a couple screws
ftaimages.jpg

img%5D
my.php
ftaimages.jpg

Interesting that you should post this. I had done a prototype of this a month or two ago, and just today, I cleaned it up so that it was more adjustable.
I'm using a QPH-031, which does sag a bit to the left when the dish is tilted over to the west horizon, however the main reason I did it was because my lnbf arm on my Fortec 90CM is an inch or two too low and to the left (viewing from the front, and the LNBF isn't at the focal point.
So I drilled two holes, not quite as high as you show, but almost. I put a bolt through that hole, and I had drilled a hole through the bolt, and ran a wire down to the lnbf support arm, and up to the other side. I was able to bend the lnbf arm enough to get the lnbf up to the proper focal point, then tightened another nut over the wire. A couple pictures below.
 

Attachments

  • for-inv_1406.jpg
    for-inv_1406.jpg
    85.1 KB · Views: 210
  • for-inv_1407.jpg
    for-inv_1407.jpg
    47.1 KB · Views: 196
  • for-inv_1409.jpg
    for-inv_1409.jpg
    74.8 KB · Views: 208
Still flimsy - wires are bad for holding LNBF on place - it's hold only one direction : down, but allow to move up/left/right; better use struts.
 
Still flimsy - wires are bad for holding LNBF on place - it's hold only one direction : down, but allow to move up/left/right; better use struts.

Very true. I know a fellow who used wires like power pole guy wires to secure his mast. There is always too much slop here and when the dish wobbled in the wind, the wires came loose and he found his dish and mast laying over on its side after several strong storms.

Stick with solid, lightweight struts of some sort. You will appreciate it in the long run. Wires and even aircraft cables, no matter how strong, still have too much flexibility. You desire that rigid structure and support.

RADAR
 
Still flimsy - wires are bad for holding LNBF on place - it's hold only one direction : down, but allow to move up/left/right; better use struts.

That may be the case if the lnbf is in the right place already, but I guarantee that isn't the case with my lnbf, since I had to stress it with probably 10 lbs of tension to pull the lnbf up into position. So it isn't moving in ANY direction, despite the apparent slack look of the wires. The wire is pretty heavy duty wire, and even 10 lbs tension didn't straighten out the kinks.

But even if you didn't have the lnbf in the wrong position, if the reason for the wires is to compensate for the extra weight, then all the force is down anyway, so I don't see a problem with using wires. Bottom line, it's a cheap solution, and struts might be better, but it can't be worse than not having them.
 
That may be the case if the lnbf is in the right place already, but I guarantee that isn't the case with my lnbf, since I had to stress it with probably 10 lbs of tension to pull the lnbf up into position. So it isn't moving in ANY direction, despite the apparent slack look of the wires. The wire is pretty heavy duty wire, and even 10 lbs tension didn't straighten out the kinks.

But even if you didn't have the lnbf in the wrong position, if the reason for the wires is to compensate for the extra weight, then all the force is down anyway, so I don't see a problem with using wires. Bottom line, it's a cheap solution, and struts might be better, but it can't be worse than not having them.

B.J.

My brother ran into a case with a brand new dish where the LNBF support arm was not correctly formed (the bend where the arm passes under the lower perimeter of the dish was not fully complete). No wire or struts would have corrected this. He physically had to finish the bend that was not done fully at the factory.

This was not a difficult task, but if it is your first NEW dish, how would you know that it was wrong without going through a lot of frustration. This was on a Winegard DS-2076 dish. The LNBF support arm on that dish cleared the bottom perimeter of the reflector plate by 2-3 inches. On my dish, it barely cleared it by 3/8". We soon picked up on this difference and corrected his dish by bending the arm properly (completely). That dish is still in use somewhere and doing fine now.

A person has to watch out for these quirks.

RADAR
 
B.J.

My brother ran into a case with a brand new dish where the LNBF support arm was not correctly formed (the bend where the arm passes under the lower perimeter of the dish was not fully complete). No wire or struts would have corrected this. He physically had to finish the bend that was not done fully at the factory.

This was not a difficult task, but if it is your first NEW dish, how would you know that it was wrong without going through a lot of frustration. This was on a Winegard DS-2076 dish. The LNBF support arm on that dish cleared the bottom perimeter of the reflector plate by 2-3 inches. On my dish, it barely cleared it by 3/8". We soon picked up on this difference and corrected his dish by bending the arm properly (completely). That dish is still in use somewhere and doing fine now.

A person has to watch out for these quirks.

RADAR

I found out that my support arm was bent before I ever put it up, via aiming at the sun with mirrors, however I was reluctant to bend a brand new dish, and it seemed to work OK even though in the wrong place. But I finally got fed up, and put it in the right place, and I did improve the reception a bit.

Re the previous post about trying guy wires to support a dish on a pole, yeah, I had a friend who put a 10' dish on a PVC pole, and he tried to secure that with steel cables, and it just pulled the anchors right out of the ground. Didn't come close to working.
 
I found out that my support arm was bent before I ever put it up, via aiming at the sun with mirrors, however I was reluctant to bend a brand new dish, and it seemed to work OK even though in the wrong place. But I finally got fed up, and put it in the right place, and I did improve the reception a bit.

Re the previous post about trying guy wires to support a dish on a pole, yeah, I had a friend who put a 10' dish on a PVC pole, and he tried to secure that with steel cables, and it just pulled the anchors right out of the ground. Didn't come close to working.

It is amazing the circumstances that we find in this hobby. Even little things that do not seem all that important on the surface can make the difference in what channels a person can receive.

I may be quite anal about my dish and motor alignment procedures. But, I think that my persistence and dedication is paying off quite well. This is great!

I only have two snares that I cannot seem to fix. RTN on 83 and the interference from Video-1 and Estrela do Sul @ 63.0W being very weak (69% Q).

Everything else is coming in with quality (on a CS 5K) in the 88-98% range. This is very good in my opinion.

I would like to chat further about other issues, but I hate to hijack Freezy's post any further. Some of this information is related to his issue, but I don't wish to go beyond that.

We will have to discuss this more in another post, I believe.

RADAR
 
I had this lnb on my 90cm fortec for over 2 years without any additional support. never had any issues even in the winter with snow/ice buildup.
 
I could say same, but noticed when I move the dish by one step, SQ is upping little bit, then return to steady value.
I feel I should install those struts soon.
 
...
I only have two snares that I cannot seem to fix. RTN on 83 and the interference from Video-1 and Estrela do Sul @ 63.0W being very weak (69% Q).

Everything else is coming in with quality ...

I haven't had any problems with RTN. It's been solid, as has Video-1/LEO. My theory is that blind scan receiver have a problem with that, while non-blind scan receivers can handle the nearby channels, but that's just a guess.
The Estrela do Sul thing really annoys me. For years, I've been tuning that sat in, getting the DCII channels there, but since i have a 4200 that requires about 50 some keystrokes to tune the DCII channels, I seldom went there. THEN, the DCII channels changed to DVB, so it was convenient to tune them in.... but 3 pine trees grew up, and blocked me. I can't get a hint of a signal off that sat anymore. Good news is that my wife want's to install a barn, that will require those 3 pine trees to GO AWAY. So I may get that sat back if we decide to go through with the barn.
Actually, there were 5 pine trees, and I already took down 2 of them, in order to get AMC6 back since I had lost NASA and the MSNBC channels, but there are still about 3 of them blocking T14 (which is what the North American sat users calls Estrela do Sul).
 
I haven't had any problems with RTN. It's been solid, as has Video-1/LEO. My theory is that blind scan receiver have a problem with that, while non-blind scan receivers can handle the nearby channels, but that's just a guess.
The Estrela do Sul thing really annoys me. For years, I've been tuning that sat in, getting the DCII channels there, but since i have a 4200 that requires about 50 some keystrokes to tune the DCII channels, I seldom went there. THEN, the DCII channels changed to DVB, so it was convenient to tune them in.... but 3 pine trees grew up, and blocked me. I can't get a hint of a signal off that sat anymore. Good news is that my wife want's to install a barn, that will require those 3 pine trees to GO AWAY. So I may get that sat back if we decide to go through with the barn.
Actually, there were 5 pine trees, and I already took down 2 of them, in order to get AMC6 back since I had lost NASA and the MSNBC channels, but there are still about 3 of them blocking T14 (which is what the North American sat users calls Estrela do Sul).

Hello Again B.J.

Great to chat with you! I am about done for the evening, but I wanted to say goodnight to you before I left the forum.

I find it great to chat with you and the other members. We certainly must keep this dialog going. Talk to you soon?
\
Take care B.J.

Gordy (RADAR)
 
I got my Invacom QWPH-031 today. Wow this thing weighs 5 times as much as my single linear only. My cheapo d-wave dish is able to hold it w/out any extra support...thank goodness.

I did get it from an ebay seller. I need to go back and read the "how to tell if you have a clone" but so far it's working very nice.

Skew isn't dead center at zero at my straight south bird but a 3 degree variance seems ok.

sw21 between the motor and lnb..right?
 
I got my Invacom QWPH-031 today. Wow this thing weighs 5 times as much as my single linear only. My cheapo d-wave dish is able to hold it w/out any extra support...thank goodness.

I did get it from an ebay seller. I need to go back and read the "how to tell if you have a clone" but so far it's working very nice.

Skew isn't dead center at zero at my straight south bird but a 3 degree variance seems ok.

sw21 between the motor and lnb..right?

LOL! Yeah, it is heavy, but remeber there are four LNBFs inside!

As for a switch, yes it should be inserted between the motor and the LNBF for best results. I have done it otherwise and made it work, but it isn't recommended. An SW21 switch may not always be supported by the receiver. Most true FTA receivers will only support DiSEqC and 22KHz switch types, so research your receiver's specs before you buy the switch.

Just thought you would like to know that in advance.

RADAR
 
I robbed the support struts off my 90 CM 3ABN dish and fitted to my 80CM Fortec Star dish for extra support!

Worked out great, added a bracket from Lowes, now there is room for one more LNB on the other side!

Now, there is no weight issue!! :up

K E V I N
ftabman0_avitar-cordoba.gif
 

Attachments

  • Fortec Star 80CM Mod With A-shine Arms.JPG
    Fortec Star 80CM Mod With A-shine Arms.JPG
    53.1 KB · Views: 200
LOL! Yeah, it is heavy, but remeber there are four LNBFs inside!

....
Assuming that we're talking QPH-031 rather than QWPH-031...

Has anyone taken one of these things apart to see how they work?
There certainly aren't 4 "LNBFs" there, since the "F" of that acronym is a feedhorn. Ie only one feedhorn. But after that, I'm curious re how it works. Ie how many probes inside. I assume that there are probably only 2 or perhaps 4 probes, and that the electronics do magic with phasing of the signals from those. I can understand how a multiport circular or linear lnbf can function, but am a bit curious re how they get both circular and linear from one feed.
But re the weight of the thing, seems like the feedhorn part should be the same, and perhaps an extra set of probes at the end of the waveguide, but it seems likely that the main extra hardware required would be 4 sets of electronics for the amp/converter. So the circuit board would have to be bigger, but those things are so miniaturized, that it sure doesn't seem like that could account for the weight. I almost think that a large part of the extra weight would be due to just the need for 4 f connectors?


One question I have about the LNBF, and I think I'll experiment with this once the rain stops and the dragonflies come out and eat these darn mosquitos, but I have always used my 2 QPH-031 with a DiseqC switch, such that only one port get's power at any one time. I'm curious relative to how the performance changes when power is applied to more than one port at a time? Ie is there any problem with leakage of signal from the circular ports into the linear, or from one polarization into the other? I have used mine with one linear port connected to a receiver, and the other linear port going to a signal meter that provides power, but I'm pretty sure that when I did this, I was on horizontal polarity on both ports. Anyway, just curious whether anyone uses one of those multi switches that would power up all the ports, and could compare performance between using only one port vs using all ports?
 
Status
Please reply by conversation.

Users Who Are Viewing This Thread (Total: 0, Members: 0, Guests: 0)

Who Read This Thread (Total Members: 1)

Latest posts

Top