Trying to get into C-Band, may have found a dish?

Ordered a DPDT switch to make moving dish easier until my pcb is done and delivered for the dish positioner.

Did you read this:



I'm not familiar with the Invacom QPH-031. Does it use/need 22kHz?
If none of your LNBs switch on 22kHz, you could indeed use an ECODA 22kHz switch, I think.
However it has constantly DC-through on both ports, I believe, so your receiver would have to supply power constantly to two LNBs and one Diseqc motor.
- So why not use a diseqc 1.1 switch? Your receiver seems to support it.
- Another option would be to use a 2/1 diseqc 1.0 switch, either "position" or "option", allowing 2 of the 4 ports of the 4/1 switch to be used for your Ku LNB. (Some old receivers, however, don't give a repeated diseqc command, as would be needed for this cascaded/serial use. However, most (modern) receivers do, I think.)

[By the way. If you don't want the motor current through the switch, you could split off a parallel line to the diseqc motor, right after your receiver, if you want. So you don't need to go to the motor and back to the switch, with your cabling. Just mentioning this as a possibility...]


For the actuator: Yes, it is clear that that construction should be changed!


Greetz,
A33
How should I adjust the actuator so it allows more movement to the left without hitting the bolt?

Should I loosen these two bolts and move actuator up or down? Or is this a matter of needing a longer actuator?

IMG_1092.jpg
 
How should I adjust the actuator so it allows more movement to the left without hitting the bolt?

Should I loosen these two bolts and move actuator up or down? Or is this a matter of needing a longer actuator?

No, best way would be to add a metal plate to the back of the mount (at the two holes, where you now can fix your actuator on), to move the actuator fixing point more to the right.
Take for a random example the picture here: anyone bought this new 1.2m dish with actuator bracket??
(Here the fixing point is not only moved to the right, but also backwards (further from the rotational axis). There are plenty of other examples to be found, I guess, on the internet.)

By no means you must let your actuator pass over the rotational axis bolt (which you are now touching, with your actuator), or your dish will 'flop' or flip or whatever it is called (possibly creating severe damage to your mount/dish/actuator)! So take care that the actuator always stays clearly on one side of it.

The actuator triangle design for satellite dishes is a very interesting, but rather neglected subject, I find.
The above proposal is just one (the simplest) solution, I think.

Greetz,
A33
 
What side of the arc has the lowest elevation satellite? You want to mount the motor on the side with the lowest satellite. The motor will then PUSH up from the lowest satellite and not pull through the "flop" point.

If you need to provide more clearance for the actuator arm, many times we have bolted or welded a "L" leg in order to mount the motor clamp six or more inches away from the current position.

Please note that the install guide for the C138 / C238 indicates that the "0" zero skew mark is aligned with the horizontal polarity. If installing the LNBF with the dish parked at the Apex (highest point South), the "0" skew stamp would align with 3 or 9 o'clock (not 12 or 6 o'clock)..
 
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What side of the arc has the lowest elevation satellite? You want to mount the motor on the side with the lowest satellite. The motor will then PUSH up from the lowest satellite and not pull through the "flop" point.

If you need to provide more clearance for the actuator arm, many times we have bolted or welded a "L" leg in order to mount the motor clamp six or more inches away from the current position.

Please note that the install guide for the C138 / C238 indicates that the "0" zero skew mark is aligned with the horizontal polarity. If installing the LNBF with the dish parked at the Apex (highest point South), the "0" skew stamp would align with 3 or 9 o'clock (not 12 or 6 o'clock)..
58W (11 elevation from my area) is on the left side looking from behind the dish (My southern sat is either 121w or 123w). I guess I'll move it back to the left side then and try again looking for some sats.

Okay so right now I have the "0" position aligned to 12 o'clock on the dish, this explains why I am not able to use the 13/18v setting then.

Today I ran a 2nd wire directly from the LNB without a switch and still needed 18v to get the V TP. Tomorrow I will try and rotate the lnb and hopefully that was the issue.
 
Yeah.
I wrote that twice... :(
Ah, just realized that.

Regarding the extension bracket, is there a specific spot/length that it needs to be? Or I can just extend any length as long as it’s mounted from the original hole?
 
I see from your signature that you live in California (like myself). If you install the arm on the east side of the reflector, you should easily reach the western-most active satellite (135w) without any modification to the mount.

No recommendation on the length or position of the "L" leg extension if one needs to be added. Don't want to drive past the "flop" point. The position and length varies between models.

Many of us fabricated a new the arm connection point and added an "L" bracket (on the reflector end) further away from the mount. This would provide increased travel before the "flop", allow the use of longer actuator arms and increase the counts per degree for improved accuracy.
 
I see from your signature that you live in California (like myself). If you install the arm on the east side of the reflector, you should easily reach the western-most active satellite (135w) without any modification to the mount.

No recommendation on the length or position of the "L" leg extension if one needs to be added. Don't want to drive past the "flop" point. The position and length varies between models.

Many of us fabricated a new the arm connection point and added an "L" bracket (on the reflector end) further away from the mount. This would provide increased travel before the "flop", allow the use of longer actuator arms and increase the counts per degree for improved accuracy.
Yes, in California.

I can easily reach 135w with the actuator mounted on either side.

I was trying to get to 58W.

When you say mounted on east side of reflector, are we talking having it mounted on the right side when behind the dish(want to make sure I am understanding everything correctly).

Can you get 58W from your location?
 
The east side of the dish would be the left side when standing behind the dish. You want the arm mounted on the side with the lowest elevation satellite that you are targeting.

From my previous business location in Roseville, CA, could receive down to 55.5w. Here in the foothills, the hills and trees limit me to seeing down to about 80w to the east, but receive out to West to 166.0e (hasn't been much to see past 139w on C-band).
 
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58W (11 elevation from my area) is on the left side looking from behind the dish (My southern sat is either 121w or 123w). I guess I'll move it back to the left side then and try again looking for some sats.

So that would mean >70 degrees rotation from due south, I guess!
Going back to the left side with your actuator (as Titanium advised), without an extension bracket, would be a good solution indeed.
It would mean that the actuator-bracket should be right at the top of the actuator tube, I guess; or otherwise you might not reach 58W with fully retracted actuator.
(If you cannot reach 58W this way with the actuator bracket at the left hole at the back of the mount, you could probably use the right hole of the mount. But then your range to the other direction of due south will decrease a lot. I won't repeat the flopping risk...)


Many of us fabricated a new the arm connection point and added an "L" bracket (on the reflector end) further away from the mount. This would provide increased travel before the "flop", allow the use of longer actuator arms and increase the counts per degree for improved accuracy.

How I understand the actuator triangle goniometry:
- total stroke length for the receivable arc is about twice the length of the shortest leg of the triangle;
- the actuator length must of course be a bit longer than this total stroke length;
- making the longest leg of the triangle longer, doesn't increase the total stroke length; it results in the possibility of having the actuator tube bracket not on the top of the tube, but more towards the base of the tube;
- with the two legs of the triangle equal in length, the stroke length (and number of counts) per rotational degree (and therefore the positioning accuracy, and movement power) is highest at the fully retracted zone of the actuator;
- when having one leg of the triangle longer than the other, this zone of highest power and highest accuracy shifts more towards the halfway extended zone of the actuator;
- however, the longest leg would normally not be longer than 3 times the length of the shortest leg (resulting in having the actuator tube bracket at the base of the actuator tube); so I guess about twice the length of the shortest leg would be a practical and sensible choice, to spread accuracy and power a bit.

When the leg lengths of the triangle are chosen (one leg almost half of the actuator length!), comes the actual choice/fabrication of the actuator fixing points, for the most retracted satellite position.
These points should preferably be as close together as possible/reasonable, possibly using extension brackets (L-shaped or other); so that you have more power and accuracy, and less chance of flopping, at the extended side of the actuator.

[ All these are approximations, as a rule of thumb, assuming the actuator tube bracket (as an influencing factor) has negligible dimensions.
It is not difficult to enter the size of the actuator tube bracket into the calculations, however, and do very precise calculations.
By the way, I've seen an example where especially the relatively greater size of the actuator tube bracket diminished the chance of flopping! ]


So if I had an polar mount setup with actuator (alas I have not), and wanted to make full use of it, I'd choose the fixing points of the actuator on the base of such an actuator triangle design.

I know this subject isn't discussed often, but I hope I've explained the principles and how I understand them somewhat understandable.

greetz,
A33
 
Thanks, I will do the actuator set-up tomorrow. Just got my DPDT switch to make life easier moving the motor around.

So I turned the LNB 90 degrees as suggested by you both. I can receive signal using the 13/18v option now =D

I also connected my SV HD8000 and it also receives 125w DVB-S TP 4149V now so the 13/18v problem is indeed fixed.

Should be easier to find sats now too leaving it at 13/18v instead of having to constantly switch the setting.
 
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