johnhenry
I think you might have posted this in the wrong thread, as I started it in order to find out more about how to fit additional LNBs to an existing dish and what bits I could use - rather than how to then set up the LNBs and receivers to scan the satellites (which is what your post seems to be about).
Actually, it looks like Imight need to drill a hole (or2?) in the existing LNB holder neck and put a bolt through that (which should not be a problem if done carefully).Originally Posted by echelon
Another feature about having 3 Lnb's fitted comes when we have a bad winter when snow about (how ever not this winter), one of my Lnbs (19e) froze up and stopped working but thankfully 13e and Thor kept working so I still had satellite programmes to watch. Just two days later 19e came back after snow melted. My bracket is still supporting the same original 3 Lnbs I fitted in 2010.
I definitely would never do that, not at all , if only to stop water ingress
these triple clamps mean one goes AROUND the existing lnb neck, if it has room to fit 2 collars, the original collar and the clamp collar , which is why you need a long neck lnb in the prime position
this is exactly how it was done in the picture that you posted earlier
when it comes try it on a spare lnb and you will understand
see my attached picture, the centre clamp goes around the neck of the existing lnb
I take your point about water ingress in general - which would be easy to stop with a little silicone sealant anyway - , but even it does get into the holder then it's not going to get into the neck of the LNB itself because there would still be no hole in that (If that is what you are concerned about?) but maybe is going to run down the inside of the arm and then out the other end or somewhere else inconsequential!
I think you would damage the lnb, because there must be something inside that neck
plus its irrelevant , because the middle holder clamps around the lnb neck, no drilling required
an alternative is one of these like I used on a zone 2 sly dish many years ago
Again, I think there is a little bit of a misunderstanding: if you look carefully at the picture (from another forum BTW) that I attached to Post 18, then that is EXACTLY what was done - the bolt in question (the 3rd from the Right) passes through the body of the LNB holder BELOW the actual LNB, and therefore there should be no possibility of damaging the latter (provided that the head of the bolt is not too large and thus pushes hard against the LNB body)
I think there is a misunderstanding but on your part not mine
that bolt does NOT pass through the lnb in my opinion, its below the lnb and if you look at where the 3 lnb neck holes are you would see that they are in a line above it
that bolt and the 4th from the right as well hold the lnb holder in place which is actually clamped onto the long neck of that lnb as I keep telling you
the 6 bolts fasten the 3 lnb holders to the metal adjustable bracket , no bolts go through that smart lnb , sorry , but they dont , look at the picture I posted in post #25
I have fitted a couple of these myself elsewhere and can assure you that no drilling of the lnb is required
I looked at that sort of thing as well - but the issue of the dimensions of the arm V the unknown dimensions of the "saddle" at the "front" of the bracket caused me the same problem as the one I started this thread about!
PS: it really would be nice, but far too much to actually expect, if people selling these things gave some dimensional or other info that allow you to clearly understand what something is designed to fit on (even "for TRIAX" etc. would be a help). Some are even worse that that - I saw one advert with a picture of the BOX supposedly containing a holder but no picture at all of the holder itself or details of the design etc., and another with a picture of some sort of bracket/holder inside a sealed plastic bag but again no details of what it actually was! How DO people expect to sell something when they do that?
I know , and I fully agree with you , which is why I am trying to help you seeing as I have bought and used and adapted these parts myself over the years
Actually I think we might be talking at cross-purposes on the issue of the "hole" because, in my case, I would not be using the centre LNB holder on the new bracket to attach it to a "smart LNB" (or any other LNB) already fitted in the existing dish LNB holder because I think the 40mm sections of the necks of most of my existing spare LNBs are not long enough to allow me to attach them to both holders at the same time.
Therefore the " new hole" would be through that existing dish arm LNB holder, and below the LNB fitted in that position - and a longer bolt would obviously be used.
I know that, and thank you! - but please see Post 32.
PS: I've "adapted" a few things over the years. Attached image shows how I fitted a standard Sharp Universal to my old (1991-ish) NEC 3000 80cm dish - which was said to be "impossible" to do - and got it spot on the focal point!
Still there about 20yrs later - but I doubt the Sharp LNB still works !
fair enough , but if you read my posts again I did mention that you need a long neck lnb at the main focal point where the existing single lnb holder would be (in other words you may need to buy and fit one there too) and I was giving you the official version of how it all works in practice
the lnb rack you have bought is designed to clamp aroung a long neck lnb and then fit one or two lnb,s in the spare holders, more importantly it allows you to "spin" the whole thing around clockwise or anti-clockwise on the existing long neck lnb until the rack is at the correct axis in relation to the holder, so on a slant is what I am saying
only when its on the correct axis (skewed) , which is not horizontal , will you be able to adjust the other 2 holders to pick up an extra 2 satellites close by
only when you have done the above alignments could you drill the existing lnb holder and fit the bolt , possibly a new bolt as well as those 6 bolts above, possibly replacing one of the middle ones with a longer bolt if it actually manages to line up and allow you to clamp the new rack to the existing lnb holder
but you cannot just drill the hole and bolt it up without getting that skewed plane right , plus you wont be able to adjust it clockwise or anticlockwise to get the axis right either, once its bolted up , unless your new bolt allows for that action too
I have just jury rigged up one of those racks with a new inverto long neck 40mm lnb and added the triax lnb holder as well for you to look at how it works in practice the way its designed to work, with no drilling required and maximum adjustment allowed, you can see the double clamp around the neck quite clearly , plus the outer lnb holders are in alignment with the middle one too in all directions
see the pics below
digicon (11-02-2016)
Echelon
Many thanks for that, and I certainly did miss the point about the long-necked LNB in your earlier post but, as luck would have it, I do already have one - and it's the twin of the Sharp White Universal shown fitted to the NEC dish, and that one still does work as I checked that over the weekend (it spent the last 20 yrs or so indoors and unused)!
So, maybe I'll use that in the configuration you mentioned and then, when the tilt angle is determined, replace it with one of the short ones - pity that none of the adverts for these give enough info to make all this very important details clear (at all!).
Thanks again!
echelon (10-02-2016)
excellent , that should work and allow you to determine all the correct angles and skews and yaws
once done, its either leave the long neck one in place or bolt the new holder to the existing holder in the manner you describe, providing it doesnt pitch up or down or cause other alignment issues, I think my pictures made it clearer to you and I now see you meant to drill the existing lnb holder and not the actual lnb itself
so cross purposes on both sides but I believe as practical people we got there in the end
let us know how you get on, its very interesting to say the least
one other method I thought of was bolting some sort of L bracket to the dish arm underneath and bolting that new rack onto the upright of the L shape in some manner that allows the same issues to be sorted out even if it needed trimming with a hacksaw
Now here's another weird thing!
I have finally finished all the gardening work for the meantime and can get back to setting up the dishes - when the weather is OK - and that will also involve a replacement of my old NEC steerable dish & mount by another "new old " dish and mount (which will now be a new Diseqc mount).
Here's the "weird" bit - the "new old" dish is white-painted steel, approx. 98cm high and 86cm wide, and has a "very TRIAX" looking folding arm on it with those 50mmx 20mm outer dimensions we talked about earlier - so it looks, armwise, like a TRIAX dish BUT the dish size does not seem to match with any of the current TRIAX sizes and there are absolutely no manufacturer's trademark or other markings on it.
Having done a few web searches I can't find anything to match it, and so does anyone know whether this might be an older TRIAX design or a rough clone thereof, as I want to try to get the dish specs and especially the offset angle
Thanks in advance.
Last edited by jallen01; 12-03-2016 at 06:15 PM.
Update on 8th March post FWIW
It looks like this latest dish IS a TRIAX but possibly an unmarked contract version - but there is an intriguing thing that I found:
- Some retailers DO sell a 98cm TRIAX and show the TRIAX part number as 122901 (in keeping with the rest of the TRIAX TD dishes, the "9" appears to signify a 98cm dish - which "fits" this one)
- OTOH, the actual TRIAX catalogue, and the listings on many major retailers' sites, show part number 122901 to be the TD110 110cm dish, and no 98cm dishes are listed at all!
So it seems that TRIAX appear to have used the 122901 number for two different sized dishes, and the 110cm version is what you will now generally get at about £60-70 retail (unless you look on AM*Z** where you can double that price)!!
Makes the tenner I paid for this one AND a Silent Gold SM 99 mount from the local council waste site quite a bargain, even if it was 10yrs or so ago!
Last edited by jallen01; 12-03-2016 at 07:11 PM.
echelon (12-03-2016)
FWIW reference the 3-way LNB holder shown in Post 18, I've just fitted the two of them to two dishes and found a few problems:
- had to cut off material from the lower edges of the existing LNB holders on both dishes because the large heads of the 2 posidrive bolts which secure the centre LNB to the slotted bar were fouling those existing LNB holders and were both preventing that LNB sitting in the existing holder at the correct angle and also prevented the bar being skewed to allow the LNB at one end to be higher than the one at the other end.
- The new LNB holders are quite fragile near the edge that is secured to the slotted bar - one was already snapped before I fitted it, and another one snapped as I trying (gently!) to open the top to slot in an LNB. "Repaired" those with cable ties around the breakage point - and reinforced another one before I even try to fit an LNB. Just ordered a 3rd LNB holder set to get some spares for the future :-(.
- Had to fit a couple of the LNBs (Comags FWIW) upside down because a lot of the body sticks out at 90deg from the axis of the LNB and is very close to the 40mm diameter part of the body, and thus fouled the nuts on those bloody posidrive bolts! Choose your LNBs carefully if you use these 3-way holders.
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