Just Sharing This My Channel Master 1.8 project.

[nelson_b]

yes, and getting same signal as me on that TP on my 1.8m - well done mate
both our 1.8m's have been repaired now. lol
get a coke bottle on the end of that LNB and try and peak signal to 10.5db and your laughing.
i notice the FS1, FS2, FS3 TP is weaker, and disappears "at night", and comes back...whereas the ESPN stays 24hours.

I,m leaving the dish on this sat with this l.n.b. for a day or two now - to monitor signals and tinker with the l.n.b positioning as i,m not sure its 100 % ... I will fit my Rimantss holder so i have full adjustment etc - i may not get any further improvement with C band ... the real test of the repair will be when i put it back to K/A for the Newsnet feeds. which is what i,d been using the dish for prior to the damage.

 

[nelson_b]

Looks a great repair Nelson, can't tell from the picture..

Cheers - scopus
the damage was more extensive than i originally thought .... It was a multi stage job to fix it .. i took pictures of all the steps involved - so i may start a thread sometime to show the work involved it restoring it .

 

[scopus]

Cheers - scopus
the damgae was more extensive than i originally thought .... It was a multi stage job to fix it .. i took pictures of all the steps involved - so i may start a thread sometime to show the work involved it restoring it .

Nelson,

Yes, would love to see the stages of repair..it looked really badly damaged in the first picture..

 

[Manikm909]

I,m leaving the dish on this sat with this l.n.b. for a day or two now - to monitor signals and tinker with the l.n.b positioning as i,m not sure its 100 % ... I will fit my Rimantss holder so i have full adjustment etc - i may not get any further improvement with C band ... the real test of the repair will be when i put it back to K/A for the Newsnet feeds. which is what i,d been using the dish for prior to the damage.

i bet it will be no worse off.

 

[nelson_b]

i bet it will be no worse off.

I optimized the l.n.b position today --- but got no no further gains in C band at 40.5 W... out of interest i did a string test on the dish and its about 2mm out of true .... i,v a feeling that may be enough to affect the K/A reception - as it is so ultra sensitive compared to C or K/U - be interesting to see by how much ?

 

[John]

I optimized the l.n.b position today --- but got no no further gains in C band at 40.5 W... out of interest i did a string test on the dish and its about 2mm out of true .... i,v a feeling that may be enough to affect the K/A reception - as it is so ultra sensitive compared to C or K/U - be interesting to see by how much ?

with you on that one our Nelson .

As promised ... Finally - Today i got some time to check out the "repaired 1.8 " .... first test out of curiosity - the ESPN transponder at 40.5 West ..

and yes i,m happy with the result so far ....

View attachment 142414 View attachment 142415
pic of the worst bit of the of the winter storm damage ..

View attachment 142416

... looks like a new 'un, good job done.

 

[Manikm909]

this whole string test thing puzzles me I must admit - is there a dummies guide on how to do it...?

btw i had no luck at all with @RimaNTSS holder offset for CBAND LNB - just doesnt want to pick up a signal if not central.

so because of that, currently the 1.8 is camped out on 40.5w for ESPN....not using it for anything else at the mo.

 

[Manikm909]

hi guys
in post #666 (lol) above - does anyone know how the guy might have accomplished getting CBAND lnb on top of his KU band lnb (i have PM'd him)
this is what i want to do based on total failure of offset CBAND lnb

 

[moonbase]

hi guys
in post #666 (lol) above - does anyone know how the guy might have accomplished getting CBAND lnb on top of his KU band lnb (i have PM'd him)
this is what i want to do based on total failure of offset CBAND lnb

It looks looks he has two rectangular split collars around the neck of the 40mm Ku band LNB, front and back.
The upper edge of each of the two rectangular split collars looks like it has a metal plate secured to it that has some type of fixing to clamp the C-Band LNBF.

 

[Manikm909]

do u think i could do something with this and my existing @RimaNTSS setup

https://www.amazon.co.uk/Maclean-MCTV-565-Mounting-Accessories-multifunctional/dp/B0725CVNGB/

 

[nelson_b]

this whole string test thing puzzles me I must admit - is there a dummies guide on how to do it...?

btw i had no luck at all with @RimaNTSS holder offset for CBAND LNB - just doesnt want to pick up a signal if not central.

so because of that, currently the 1.8 is camped out on 40.5w for ESPN....not using it for anything else at the mo.

Hi for demonstration / photograph purposes i have used some rope .. in reality you need to use fishing line stretched tight across the dish face horizontally and vertically ... then you view the dish from the side ... if the dish is perfect the strings will be touching in the center where they cross



if the dish is warped ... there will be a gap between them where they cross ...... you could add diagonal strings too as i do on the paneled prime focus Prodelin .

 

[Manikm909]

Hi for demonstration / photograph purposes i have used some rope .. in reality you need to use fishing line stretched tight across the dish face horizontally and vertically ... then you view the dish from the side ... if the dish is perfect the strings will be touching in the center where they cross

View attachment 142445

if the dish is warped ... there will be a gap between them where they cross ...... you could add diagonal strings too as i do on the paneled prime focus Prodelin .

thanks

oh i thought this was to locate the LNB G-spot

 

[nelson_b]

btw i had no luck at all with @RimaNTSS holder offset for CBAND LNB - just doesnt want to pick up a signal if not central.

Indeed if signal is only just above lock when central .... its unlikely to lock on side offset ... i have a wide offset on the 2.4 C.m. due to the sub reflector - and it makes the offset l.n.b,s a fraction less than they would be if central on a 1.8 .... I,v never tried an above offset on my c.m 1.8 ... so cant say if there is some loss or not when its offset in that way .. hopefully less than a side offset

 

[moonbase]

do u think i could do something with this and my existing @RimaNTSS setup

https://www.amazon.co.uk/Maclean-MCTV-565-Mounting-Accessories-multifunctional/dp/B0725CVNGB/

If you removed the bar that joins the two 40mm collar sections so you have two separate 40mm collars you could use them front and back on a Ku-Band LNBF.
All you would need to do would be to make some type of plate that could be bolted to the top edges of the collars and fix the C-Band LNBF to that.

If you have any breadboard left if might be OK for the plate? Alternatively, a piece of 2mm thick aluminium or steel plate should to the job?

 

[scopus]

Hi for demonstration / photograph purposes i have used some rope .. in reality you need to use fishing line stretched tight across the dish face horizontally and vertically ... then you view the dish from the side ... if the dish is perfect the strings will be touching in the center where they cross

View attachment 142445

if the dish is warped ... there will be a gap between them where they cross ...... you could add diagonal strings too as i do on the paneled prime focus Prodelin .

Just strung my 1.8 Precision just as a check...all OK..

 

[a33]

To be sure, with the stringtest, do not just test with strings hor and vert (like " + "), but also diagonal (like " x ").

That is because in theory, when it is warped diagonally, the hor/vert test could turn out OK.

I believe (but I'm not sure) that most common warpedness is that left and right of the dish should be pulled more backwards (towards the dishmount/pole).

Greetz,
A33

 

[scopus]

To be sure, with the stringtest, do not just test with strings hor and vert (like " + "), but also diagonal (like " x ").

That is because in theory, when it is warped diagonally, the hor/vert test could turn out OK.

I believe (but I'm not sure) that most common warpedness is that left and right of the dish should be pulled more backwards (towards the dishmount/pole).

Greetz,
A33

I see your point, perhaps the X strings would be more of use on a petalised dish. The Precision is a one piece spun aluminium dish..

 

[Channel Hopper]

I see your point, perhaps the X strings would be more of use on a petalised dish. The Precision is a one piece spun aluminium dish..

A string test on a small, prime focus reflector (petalised or not) can be checked by looking along the dish rim towards the opposite side, but is best carried out by placing face down on a known flat surface. (a frozen pond works well) .

 

[scopus]

A string test on a small, prime focus reflector (petalised or not) can be checked by looking along the dish rim towards the opposite side, but is best carried out by placing face down on a known flat surface. (a frozen pond works well) .

Think my perfectly flat workshop floor would suffice. Tried a frozen pond have you?

 

[Manikm909]

Think my perfectly flat workshop floor would suffice. Tried a frozen pond have you?

Sounds risky to me. You could fall through it .