Telescoping Home Antenna Mast
(THAM)
 |
| Image 3 |
The diagram at the left shows the routing and layout of the pulleys and cable connections. It took some thinking and planning to scale Bruninga's design down to this small size of EMT that I chose to use (1", 1 1/4", 2"). I tried to find a way to use the existing pulley at ACE as they have a good selection but in the end I found that I had to take their pulley apart and make my own custom brackets to hold the pulley wheel itself at the correct position to minimize any cable binding during operation.
Notice that edge of the top pulley on the 1 1/4" & 2" EMT; it is positioned just inside the lip of the tube. This required some cutting (photos later) so the cable could come up and fee directly onto the pulley.
FYI, the lower pulley on the 1 1/4" EMT is positioned further out to the left as you can see in order to position the cable parallel to the tube. This helped in reducing any cable friction at the top of the 2" conduit.
Something this first image does not address is the need for shimming to keep the tubes straight. This is discussed later on.
