I spent the afternoon yesterday putting up a CM 3679 with a 9521A rotator and a 7777 preamp.
According to antennaweb, I'm about 15 miles from my local stations in DC
and about 45 miles from Baltimore and Annapolis (PBS). I've always
gotten Balt and Annapolis on analog with some snow but never digital. My
house is single story between two two-story homes with trees.
I had installed my last antenna about 12 years ago, a Radio Shack
'suburban' VHF/UHF antenna (similar to a CM 3016). I also installed a separate FM antenna on the same pole. The TV signal was split to feed two rooms. There was no amplifier and the antenna was fixed pointing essentially toward DC.
I had intended to reuse the same chimney mount and pole for the new
antenna and rotor. But when I got everything on the roof I found that
the old pole which was in sections had rusted together. Also, the
chimney mount bolts were heavily rusted as well as the old antenna
mounting bolts. So I removed the old antennas (broke rusted bolts), pole
and mounts and made a trip to Radio Shack. I returned with a new chimney mount kit and two 5' poles.
The new mount went up uneventfully. To prevent rust, I spray painted it
with some Krylon I had lying around. The 9521A rotor is well-built. It requires a 3-wire cable for connectivity. The wire does not have to be very large, but the longer the cable run the heavier the cable. Mine was 18-guage since my run was short. The instructions with the rotor state that the antenna should be no more than 3' about the rotor for stability and wind loads. Also, the rotor should be installed so that an arrow on the case points North. A 5' pole placed the rotor above the top of the chimney. I cut a 3' section from the remaining pole for the antenna.
The 3279 comes in two sections. It is jointed with two machine screws
and wingnuts. There are two metal 'rods' that join the VHF section to
the UHF section electrically and are also attached with wingnuts. Once
the two sections are joined, the antenna is over 10' long but is not
heavy. The unit also has a balun (300 to 75ohm transformer) and mounting bracket. I attached the mounting bracket to the pole, attached the 75-ohm antenna lead to the balun, attached a standoff and raised the
antenna and installed it in the rotor, making sure it was pointing due
North. I attached additional standoffs to the pole and ran the existing
antenna wire down the pole and down the wall of the house as before.
[I left the FM antenna for later on.]
At this point I wanted to see if the signal had improved without adding
the 7777 amp so I climbed down to finish the rotor install. I ran the
wire through the wall where the old cable entered the house. I connected
the 3 wires to the back of the 9521 controller and powered it up. Since
this was the first time it was powered, it went through SYNC function
which turns the rotor to '0' degrees. The control unit is not very big,
about like a paper-back novel. It has an infrared remote and is powered
by a brick transformer with a 4' cord. You enter a degree (000-360) for
direction and it starts turning immediately. The unit can also be
programmed by channel number to remember the direct it needs to point.
With this and the right kind of programmable remote you could have the
dish move whenever a channel change is sent to your tuner.
I commanded the rotor to point toward the towers and then checked the digital signal meter in my ATSC tuner (Samsung TS160). I was disappointed to see that the signal level had not improved that much (from about 66% to 75%). I checked other stations that I could not received before and also there was no joy.
So I pulled the 7777 out of the box. This unit comes in two parts, an outdoor amp and an indoor power supply. The outdoor amp attaches to the pole near the antenna. The indoor power supply provides DC voltage to the amp. The 7777 has switches inside for setting an FM trap as well as VHF and UHF amplification. The default is for FM trap Active and both VHF and UHF amplification active. I used the defaults. Since by now it was dark I installed the amp inside for now just to see the difference in signal.
With the amp, signals that had been %60-%70 went to %100. WMPT HDTV signal in Annapolis came in where it had not been before. Unfortunately, I was not able to get any of the Baltimore digital channels.
To complete the installation, I will move the amp up to the pole. I will also move the splitter to the second set. The original pole was ground but I need to move it to a better location. And I think I'll use an old sat dish pole mount for the FM antenna.