Channel Master/Laminas 1.8m project

[moonbase]

CJ,

What size rose joints did you use for the pivot axis on the CM 1.8m, there is a lot of weight on that axis?


Thx

 

[moonbase]

CJ,

Another question if you can please confirm a point?
Is the polar mount that the dish back plate is attached to a Precision triangular polar mount modded with the addition of some angle iron bracketry?

Thx

 

[Captain Jack]

Yes, I do notice that if I optimise on one polarity, the other one suffers. I will check out the probes! I take it they are not coated with anything special and I can just move bend them with my finger or pliers?

 

[Captain Jack]

What size rose joints did you use for the pivot axis on the CM 1.8m, there is a lot of weight on that axis?

They are M10's. I do have additional holes on the bottom iron angle that I can put two more in and have a threaded bar running across the whole thing but I didn't have a long enough bar for that. Might change it later on but these rose joints are designed for use as track rod ends in go-karts, so should be OK. It feels pretty solid, anyway...

Another question if you can please confirm a point?
Is the polar mount that the dish back plate is attached to a Precision triangular polar mount modded with the addition of some angle iron bracketry?

Good eye! Yep, it's a Precision mount - very sturdy as you know and more than man enough to take the dish.

The weakest point is the declination jack, which is at an awkward angle, in tension and only held by single bolt. Need to change that too.

 

[moonbase]

CJ,

Thx for the quick reply, most appreciated.

If you get a spare minute or two, would you please be able to upload one or two pics on how you modded the Precision polar mount with the angle iron bracketry? I have an identical mount in the loft lying idle that needs a use. Precision made these mounts with huge overkill for antenna size, they are very robust and can accept quite heavy and large antenna.

Rgds

 

[Captain Jack]

There's a thread on this - Precision Polar Mount Project

 

[moonbase]

There's a thread on this - Precision Polar Mount Project

CJ,

Thx, I forgot about that topic, I should have remembered as it inspired me to buy an Evolution mitre saw.

Rgds

 

[John]

CJ,

Thx, I forgot about that topic, I should have remembered as it inspired me to buy an Evolution mitre saw.

Rgds

Me too ;)

 

[Captain Jack]

I must have missed out on my commission

 

[Captain Jack]

As my Laminas is down with no decent way to attach a couple of C band LNBs, I started (and almost finished) adapting the existing boom arm and making new arms - all as per @Trust1's measurements and angles. Have to drill a couple more holes and then it's back to the dish to fit it all.

 

[John]

As my Laminas is down with no decent way to attach a couple of C band LNBs, I started (and almost finished) adapting the existing boom arm and making new arms - all as per @Trust1's measurements and angles. Have to drill a couple more holes and then it's back to the dish to fit it all.

View attachment 98013 View attachment 98014

The new Cband gadget could be on your doorstep at the end of the week CJ if Customs & RM get their finger out then you will only need the one unit to get you L-R-H-V

 

[Captain Jack]

Whoohoo! Sadly, I don't really have any skew control bits to rotate the thing for linear polarity, so it will have to be a circular only device

Of course, if you have any "spares" for the above, then let me know! And then I'd need to figure out a way to run a 3 core cable from inside my cave to the bottom of the garden (the cabling is all in a plastic trunking partially underground so not very accessible...)

 

[John]

Whoohoo! Sadly, I don't really have any skew control bits to rotate the thing for linear polarity, so it will have to be a circular only device

Of course, if you have any "spares" for the above, then let me know! And then I'd need to figure out a way to run a 3 core cable from inside my cave to the bottom of the garden (the cabling is all in a plastic trunking partially underground so not very accessible...)

Do it by hand for the time being CJ, i think it will have some sort of grub screw thingy tapped into the side of the barrel to lock down onto the Zinwell. With your 1.8 nice and easy to get to it could be another helpful task for your beloved to participate in the hobby to go out and turn the Zin to the right position for H/V and lock off ..... what do you think ?

 

[Captain Jack]

Ha! I have more chance of making the whole thing from scratch successfully than getting her to run back and forth to the dish in the middle of winter...

 

[Captain Jack]

Changer attached. Not really fine tuned as did it during my lunch break but signal level seems OK (though not as high as on "native" arms).

 

[Captain Jack]

From a distance my dishes looks a tad small......

 

[Archive4]

From a distance my dishes looks a tad small......
View attachment 98190

Should be on Nature pics!

 

[nelson_b]

From a distance my dishes looks a tad small......
View attachment 98190

Indeed it does --- Now that the Neighbours have got used to this one, they will never notice when you introduce a "slightly" bigger one

 

[archive10]

From a distance my dishes looks a tad small......
View attachment 98190

Nono - it's brill. Just what the doctor ordered...

 

[Channel Hopper]

From a distance my dishes looks a tad small......
View attachment 98190

That field behind you could be worthy of a Jodrell Bank type contribution.