Polar mount: Elevation calculation problem

Please send several images to eric@satsig.net by email and I will add them in here.

Amongst the images a full side view, while the mechanism is centralised would be helpful.

Amended:

These are the key adjustment angles for your polar mount:
Polar mount main axis angle (deg): 60
Polar mount dish offset tilt (deg); 7.42

The main axis angle is straightforward. It is the red angle I have marked in the image. At present it is set to 71 deg, so it needs some adjustment.

The small downward tilt of the dish is less clear as I can't quite see how to do it. There are two possibiities:

1. The small downward angle is to be achieved by setting the top bolt C slightly longer than bolt A. Does it look like this is the intended method ? Is there sufficient thread on the bolts to allow the top distance C to be increased a bit and bottom distance A to be decreased? If so, measure distance B in mm and multiply by tan(7.42). i.e. 0.13 x B mm. The result is the required difference in lengths of bolts A and C. Bolt C must be the longer. You need to get the gap to 7.42 deg. At present, the gap is more like 0 deg.
There is a similar explanation here: https://www.satsig.net/pol_ex1.htm

2. If the two bolts are not adjustable, consider part D. Is there some way this part may be lengthened ? For example is there a a slot or slots where it attached near the top of the axis. There may even be scale, range 0 to 10 deg on the slot. If there is a scale use it. If not, adjust till you find the due south satellite. Can you adjust so that the purple angle = 22.6 +7.4 = 30 deg ?

Note that the generally triangular shaped bracket arrangement behind the dish is probably intended to cancel out the beam offset (22.6 deg) so that the line along B is at right angles (90 deg) to the beam direction. Is the purple angle 22.6 deg ?  Do the elevation angle calculation for an imaginary satellite at 17.9E and you will be spot on.

Concentrate all your efforts on finding and peaking up on the satellite nearest to due south (I suggest Astra at 19.2E), with your motor mechanism almost centralised, with the motor pre-set just 1.2 deg to the left (while facing south). Use this page https://www.satsig.net/maps/satellite-tv-dish-pointing-uk-ireland.htm and drag the map across till you get to Stockholm.

wxw
Best regards, Eric.

Both nuts must be fully threaded onto the bolts for security. The rose (spherical) joint bearings on the ends are intended to allow the axis to be altered slightly. There should be no need for new hardware. There must be some intended way of setting it.

The small downward adjustment angle varies over a range of about 0 to 9 deg, according to latitude.

Maybe the purple angle already incorporates some portion of the 9 deg. e.g. 22.6 + 4 deg. That would allow the length of the bolts to be adjusted +/- 15mm say.
What is the purple angle ? If the back of the dish is parallel with the front of the dish then 22.6 deg is a probablility as this would cancel the offset angle. In other words with the rear line B vertical the beam is horizontal.

Did any extra spacers or washers come with the antenna ?  There are 8 bolts involved attaching the dish to the plate then to the bracket. The upper pairs of bolts could have washers added on the underside (your idea above).

With the polar axis set correct the question is: can you now adjust the dish far enough forwards and downwards to see the Astra satellite?.

Do you have any instructions with the antenna ?

Best regards, Eric.

Assumes you have pre-set the polar axis first and operated the motor so it has stopped with the dish about 1.2 deg to the left of central. You need the actuator motored to half way and then use the clamp sleeve on the actuator body to set the dish 1.2 deg left of central. Swing the whole unit sideways on the pole in azimuth till you are peaked on Astra 19.2E. The head unit on the pole will now be accurately north-south.

With the purple angle already about 30 deg (i.e. 22.4 dish offset + 7.6 deg downward tilt) you will only need to make very small adjustment of the nuts to peak up the beam (in elevation) on Astra 19.2E.

Turn the underneath top nut slowly while reading the signal strength and peak up. The weight of the antenna will make it sag down and eliminate backlash. Then lock the other nut.

Best regards, Eric.