Channelmaster Mount Hacking

[one_db_compression]

Two summers ago I joined the site and posted about getting stung on eBay with a 50 mm (rather than 42 mm) neck on a Digipower SG-2100 motor. Since then, I procured locally another Digipower SG-2100 with a 42 mm neck and got that working nicely on a 90 cm stamped steel dish.

Recently, I came into possession of three Channelmaster 1.0 m and one Channelmaster 1.2 m fiberglass reflectors and went down the archived path and deep into the rabbit hole of enthusiasts who have homebrewed mounts to facilitate attachment to motors. The Channelmasters came with one 2-3/8" pole mount and three 3" Az-El mounts. As is well-documented, these mounts are very heavy, plus they aren't going to adapt easily to the smaller motor necks.

I contemplated a few different interface designs. Long story short, the most straightforward approach - at least from a design and dry-fit perspective - is to cannibalize Star Choice/Shaw dishes that will support the 42 and 50 mm necks. Functionally, these are Channelmaster 60E and 75E reflectors whose back assemblies are flat and have a number of positions for fasteners. These reflectors are also quite common for low to no dollars here in Canada. I think there might also be compatibility option with the back assembly from a DirecTV Slimline dish. Unfortunately, those are a challenge to find north of the border, so will need to bring a few back on my next work trip south of the border. The assemblies are installed upside-down in order to mount to the motor necks, so I will need to use an external inclinometer to set things up.

Currently, I have only mocked up and dry-fit the 60E and 75E back assemblies and these have not been attached to either motor. The initial fit is very tight - maybe only off by a millimetre or two or a small fraction of a degree. This is practically dead nuts with no play or slop due to the drilled or factory holes. The bolts are essentially screwed into the wood, never mind the washers and nuts. There is nothing that I cannot fix in a few minutes with some hand tools - even laying out and drilling the other six plywood blanks I set aside. I expect the mass of a 1.0 or 1.2 with the new mount to be less than published capacity of the motor. The masses are still significant, but are still less than if using the factory mount options. I am using 5/8" plywood that has already spent 2 years outside, but will look to preserve and paint the final products. I expect the weak link to be the fasteners and gearing in the motors that are going to be strained by the associated forces.

I'm heading off on a short vacation and hope to get back to this in about two weeks. I have a closing window of opportunity before the snow starts to fly, so if any viewers have any constructive feedback, I am happy to hear it. Additionally, there is a different motor vendor with better specifications and track records, please let me know. I am not particularly concerned about incurring additional costs, as I would prefer this to be one-and-done.

Attached are a few photos of the mounts on the 1.0 m reflector.

Thanks!

 

[primestar31]

Two summers ago I joined the site and posted about getting stung on eBay with a 50 mm (rather than 42 mm) neck on a Digipower SG-2100 motor. Since then, I procured locally another Digipower SG-2100 with a 42 mm neck and got that working nicely on a 90 cm stamped steel dish.

Recently, I came into possession of three Channelmaster 1.0 m and one Channelmaster 1.2 m fiberglass reflectors and went down the archived path and deep into the rabbit hole of enthusiasts who have homebrewed mounts to facilitate attachment to motors. The Channelmasters came with one 2-3/8" pole mount and three 3" Az-El mounts. As is well-documented, these mounts are very heavy, plus they aren't going to adapt easily to the smaller motor necks.

I contemplated a few different interface designs. Long story short, the most straightforward approach - at least from a design and dry-fit perspective - is to cannibalize Star Choice/Shaw dishes that will support the 42 and 50 mm necks. Functionally, these are Channelmaster 60E and 75E reflectors whose back assemblies are flat and have a number of positions for fasteners. These reflectors are also quite common for low to no dollars here in Canada. I think there might also be compatibility option with the back assembly from a DirecTV Slimline dish. Unfortunately, those are a challenge to find north of the border, so will need to bring a few back on my next work trip south of the border. The assemblies are installed upside-down in order to mount to the motor necks, so I will need to use an external inclinometer to set things up.

Currently, I have only mocked up and dry-fit the 60E and 75E back assemblies and these have not been attached to either motor. The initial fit is very tight - maybe only off by a millimetre or two or a small fraction of a degree. This is practically dead nuts with no play or slop due to the drilled or factory holes. The bolts are essentially screwed into the wood, never mind the washers and nuts. There is nothing that I cannot fix in a few minutes with some hand tools - even laying out and drilling the other six plywood blanks I set aside. I expect the mass of a 1.0 or 1.2 with the new mount to be less than published capacity of the motor. The masses are still significant, but are still less than if using the factory mount options. I am using 5/8" plywood that has already spent 2 years outside, but will look to preserve and paint the final products. I expect the weak link to be the fasteners and gearing in the motors that are going to be strained by the associated forces.

I'm heading off on a short vacation and hope to get back to this in about two weeks. I have a closing window of opportunity before the snow starts to fly, so if any viewers have any constructive feedback, I am happy to hear it. Additionally, there is a different motor vendor with better specifications and track records, please let me know. I am not particularly concerned about incurring additional costs, as I would prefer this to be one-and-done.

Attached are a few photos of the mounts on the 1.0 m reflector.

Thanks!
View attachment 174170View attachment 174171View attachment 174172

The weight of the dish itself is NOT the biggest issue here, it's WIND LOAD that'll kill you (the motor actually). IF you do this, try to put it on a pole that's protected from wind in a cove or something that doesn't block satellite view, but will help stop prevailing winds from blowing directly on the dish.

 

[one_db_compression]

The weight of the dish itself is NOT the biggest issue here, it's WIND LOAD that'll kill you (the motor actually). IF you do this, try to put it on a pole that's protected from wind in a cove or something that doesn't block satellite view, but will help stop prevailing winds from blowing directly on the dish.

Thanks for the feedback. Yes, the torque applied to those plastic gears will shred them. My intention is to install on a NPRM at ground level, which offers fence protection to the east, south, and west, but will still give me look angles from about 85W through to 145W.

 

[FTA4PA]

Two summers ago I joined the site and posted about getting stung on eBay with a 50 mm (rather than 42 mm) neck on a Digipower SG-2100 motor. Since then, I procured locally another Digipower SG-2100 with a 42 mm neck and got that working nicely on a 90 cm stamped steel dish.

Recently, I came into possession of three Channelmaster 1.0 m and one Channelmaster 1.2 m fiberglass reflectors and went down the archived path and deep into the rabbit hole of enthusiasts who have homebrewed mounts to facilitate attachment to motors. The Channelmasters came with one 2-3/8" pole mount and three 3" Az-El mounts. As is well-documented, these mounts are very heavy, plus they aren't going to adapt easily to the smaller motor necks.

I contemplated a few different interface designs. Long story short, the most straightforward approach - at least from a design and dry-fit perspective - is to cannibalize Star Choice/Shaw dishes that will support the 42 and 50 mm necks. Functionally, these are Channelmaster 60E and 75E reflectors whose back assemblies are flat and have a number of positions for fasteners. These reflectors are also quite common for low to no dollars here in Canada. I think there might also be compatibility option with the back assembly from a DirecTV Slimline dish. Unfortunately, those are a challenge to find north of the border, so will need to bring a few back on my next work trip south of the border. The assemblies are installed upside-down in order to mount to the motor necks, so I will need to use an external inclinometer to set things up.

Currently, I have only mocked up and dry-fit the 60E and 75E back assemblies and these have not been attached to either motor. The initial fit is very tight - maybe only off by a millimetre or two or a small fraction of a degree. This is practically dead nuts with no play or slop due to the drilled or factory holes. The bolts are essentially screwed into the wood, never mind the washers and nuts. There is nothing that I cannot fix in a few minutes with some hand tools - even laying out and drilling the other six plywood blanks I set aside. I expect the mass of a 1.0 or 1.2 with the new mount to be less than published capacity of the motor. The masses are still significant, but are still less than if using the factory mount options. I am using 5/8" plywood that has already spent 2 years outside, but will look to preserve and paint the final products. I expect the weak link to be the fasteners and gearing in the motors that are going to be strained by the associated forces.

I'm heading off on a short vacation and hope to get back to this in about two weeks. I have a closing window of opportunity before the snow starts to fly, so if any viewers have any constructive feedback, I am happy to hear it. Additionally, there is a different motor vendor with better specifications and track records, please let me know. I am not particularly concerned about incurring additional costs, as I would prefer this to be one-and-done.

Attached are a few photos of the mounts on the 1.0 m reflector.

Thanks!
View attachment 174170View attachment 174171View attachment 174172

Necessity is the mother of invention, as the old saying goes. I am sure you will catch heck for using wood but if it works for now then not a problem for the time being. You can always use the wood pieces as a pattern later and swap them out for lightweight aluminum plates. I say good work!

P.S. How is it going with your Edision Mio Plus 4K?

 

[one_db_compression]

Necessity is the mother of invention, as the old saying goes. I am sure you will catch heck for using wood but if it works for now then not a problem for the time being. You can always use the wood pieces as a pattern later and swap them out for lightweight aluminum plates. I say good work!

P.S. How is it going with your Edision Mio Plus 4K?

On a long-term, permanent basis, I would be inclined to go for a metal plate as the interface. For prototyping, the 5/8 ply was a few feet away and I have all the required hand tools. After doing two of these, I can whip up a new template in a matter of minutes now.

The Edision is great. Thank you!

 

[FTA4PA]

On a long-term, permanent basis, I would be inclined to go for a metal plate as the interface. For prototyping, the 5/8 ply was a few feet away and I have all the required hand tools. After doing two of these, I can whip up a new template in a matter of minutes now.

The Edision is great. Thank you!

Glad to hear you are pleased with the Edision!

 

[one_db_compression]

A quick update...

I mated my 60E mount to my ChannelMaster 3040642-02 1.0 m reflector and to my Digipower SG-2100 and its 42 mm tube, with everything on a NPRM on my back deck. I performed a quick alignment to point south, drove the dish to my south bird at 114.9W, gave the assembly a quick twist to "peak", and I am tracking and locking from 87W through to 129W as best as one can expect (C/N of 8 to 9) in the course of 10 minutes and without using a compass or bubble level to align anything.

I have discovered the 60E mount has a mechanical travel limit that, when mounted flush at the rear of the reflector, and when compensating for the tube angle, leaves me about 1 degree short on reflector declination. This is something that I will correct with an angle grinder to take off about 2 millimeters from the left elevation tang on the pivot assembly to make it the same length as its right counterpart.

I did some arithmetic last week and started some correspondence with RimaNTSS. I can confirm that, for a 40 degree tube and this mating of a repurposed CM 60E mount on this size of CM reflector, this will only work unmodified at or below 51 degrees latitude. As the latitude increases, the dish face needs to be flatter (more vertical). Above 51 degrees, there is mechanical interference on the left side of the pivot assembly that holds the tube. Upon a quick examination of a few other 60E mounts ("the small Shaw fiberglass dish" in Canada), the left elevation tang is longer than the right by a few millimeters. I am at almost exactly 51.00 degrees latitude. So if anyone located above a latitude cut line of roughly Calgary-London-Dortmund-Astana wants to replicate this installation, they are going to need to mechanically modify the basic 60E back assembly or factor in some additional declination compensation.

Attached are some new photos. QPH-031 and universal mount from HyperMegaSat. Red habaneros, green Hungarian, and orange Bulgarian hot peppers were added for some color.

 

[RimaNTSS]

Is that the original Channel Master antenna feedarm? If not, are you sure the LNB is in tight position?

 

[one_db_compression]

Is that the original Channel Master antenna feedarm? If not, are you sure the LNB is in tight position? View attachment 174486

You have a good eye.

This rectangular LNB arm came with the dish. There are no side supports, though the dish mold can accommodate them. Originally, I thought this to be strange, as all the other documentation I have found for the Type 100 and 120 reflectors show the multiple circular, tubular arms, rather than this single, rectangular, bottom tube. I asked the original owner and he indicated that this is how he received the dish new ~ 20 years ago. On the dish itself, the rectangular notch for the tube and the associated fastener hole is inherent from the mold and is smooth fiberglass. It isn't cut into the dish after the fact. So unless there were counterfeit CM reflectors that hit the market two decades ago, this appears to be factory-spec. Is this possibly a Alaska/Hawaii model that was used for Dish or DirecTV? I do have two other CM Type 100 reflectors (with the "traditional arm configuration") stored at another location, but I won't be able to trial them with the mount for another 12 days or so.

 

[RimaNTSS]

On the dish itself, the rectangular notch for the tube and the associated fastener hole is inherent from the mold and is smooth fiberglass. It isn't cut into the dish after the fact.

Interesting! Could you post some pictures of that notch? Is there a stamp on the back of the dish with the mold number?
And what kind of LNB-holder this dish had?

 

[one_db_compression]

Interesting! Could you post some pictures of that notch? Is there a stamp on the back of the dish with the mold number?
And what kind of LNB-holder this dish had?

ChannelMaster Part No. 3040642-02
Mold No. 1 OM-02

There was no LNB holder on the arm. My guess is that it was a RCA-style LNB that would be inserted into the end of the tube, although the "usual" RCA LNBs are narrower horizontally by ~ 10 mm and shorter vertically by 3 or 4 mm. There is a hole on the top and bottom of the tube that can accommodate a single bolt. I figure it to be either 8-32 or M4, as I needed to drill it out very slightly to insert a 10-32 (~ M5).

Now this is interesting. I just went outside and checked the underside of the reflector. It is a bit like a car... most people will never look at the undercarriage, never mind clean it or do an in-depth analysis. I gave it a minor scrub to clear off some grime and dirt. This opened up a tiny gap in between the LNB tube and the bottom of the reflector. The arm mount component, after two decades of weathering and discoloration, looked like it was integral with the reflector, but is actually a bolt-on part. Clean a little bit of crud out... there is a single bolt in the bottom position, but it is not in the molded, angled hole for the set screw. In fact, that hole has never seen any surface damage from a fastener and has thin layer of factory plastic that was never reamed or cleaned out. There is no stamped part number on the rectangular bracket, so it is possible that it is a third-party piece of kit. The LNB arm plug is aluminum. While dirty, it is machined for a tight fit in the bottom hole. It does not feel cheap. A bolt and washer set secures it to the reflector from behind and not from the right position.

I grabbed a set of arms from a different Type 100. The LNB is in the same relative as the single rectangular tube when I place the two arms next to each other. In the photo, you'll notice that the bottom tube isn't currently secured as I mentioned there has never been a self-tapped set-screw in that fastener position before.

Based on the lack of marring on the adjacent fiberglass, I would suggest that rectangular arm was installed as original equipment from the first setup of the reflector.

Everyone else's mileage may vary.

 

[primestar31]

I used to collect old Primestar dishes from people that wanted them removed, and had lots of the different kinds here in Michigan. Hence my userid Primestar31. Though I no longer have any of them.

However, I've never seen one with that particular arm, so, who knows?

 

[RimaNTSS]

Yes, this is not a different mold of the reflector. I also do not think that manufacturer made this Frankensteined design. Why should they? Perhaps, one of the first owners lost original feedarms or got the original plastic LNB-holder and decided to attach feedarm from another antenna. The adapter for "new" feedarm is not difficult to make. Let me guess.... feedarm is made of aluminum 50x20mm rectangular pipe.

 

[one_db_compression]

Yes, this is not a different mold of the reflector. I also do not think that manufacturer made this Frankensteined design. Why should they? Perhaps, one of the first owners lost original feedarms or got the original plastic LNB-holder and decided to attach feedarm from another antenna. The adapter for "new" feedarm is not difficult to make. Let me guess.... feedarm is made of aluminum 50x20mm rectangular pipe.

Indeed, it is 50 x 20 mm. I agree that it is unlikely the OEM would do this. As I understand it, I am the second owner.

My current working theory is that someone was supplying higher gain reflectors here in Canada for grey market US DBS reception. This is a dish that is oversized for picking up ExpressVu or Star Choice in Canada from older Nimiq or Anik footprints. It would be an aggressive size for picking up Dish or DirecTV in Canada at the edge of the CONUS footprints two decades ago. Many offshore LNBFs from that era would have fit into rectangular arms. As I mentioned, the lower set-screw position (a M6 tapping screw, according to the CM manual?) appears to have never had a fastener in it until earlier today, so I think this was the as-originally-sold configuration. Also, the bolts on this tube look to be SAE and I believe Channel Master supplied ISO fasteners, if I am not mistaken.