: Rotors for OTA: Channel Master, Nexxtech/Archer, Yaesu, Hy-Gain, Others
2008-08-16, 09:56 PM
It has been suggested to use a rotor and an amp, i know the amp can be used but this antennais 15-20 yo and i didnt know if a rotor would actually move it, is it that necessary , how much more signal would be gained with a rotor as compared to without if the metal is frail or rusted?
Thanks for your time and expertise.:)
2008-08-17, 12:05 PM
Rotors don't get you more signal per se, they just let you get optimum positioning and/or multiple aiming directions (i.e. one at toronto, one at buffalo if you're in the GTA)
2008-08-17, 05:38 PM
I'm in the process of finding out whether we can lock onto much in the way of OTA signals from our homemade cm4221-style tv antenna before I invest in the full meal deal -- I can get some programming with the antenna standing on the lawn -- but now want to try it higher on the roof.
A friend gave me an older rotator (brand unknown -- no markings except a 7 digit number casting on the output collar) that could help in moving the beast around.
Thing is there was no controller included with the rotator and have no idea on what the input voltage would be in order to turn this thing. There is a long 3-wire flat cable that can be connected to the 3 terminal screws in the unit compartment.
And after I get it to turn then something will be needed to remotely adjust the back and forth position of the antenna.
Appreciate any ideas on how to ID the rotator, or at least determine the input voltage to drive it, and how to make up a simple [temp] controller to run it while I test the antenna on our rooftop.
2008-08-18, 11:49 PM
Many of the rotors here use a 26vac 2-phase AC motor... The motor will have three connections; common (ground), and the two phases... In the controller unit there is a 130-uf/50vac capacitor connected across the two phases and the 26-vac signal is then fed to one or the other motor phase connections... The other motor phase is developed through the capacitor delay... Reversing the 2 phase wires will reverse the motor.
The motor needs 2 phase power to run... you can't just feed any 60Hz single phase power into this motor .... so unless you know what you're doing and can make your own 2 phase power control it would be best to use a real control box.
2008-08-19, 04:36 PM
Ok. I think we may have discovered the controller that fits the rotator. It seems both the rotator and controller were made by Crown Manufacturing Ltd. (somewhere in NA). The controller model number is "Antenna Rotator Controller RC-18" and yes, they both must work together.
Any additional info on this model RC-18 ..user guide, parts list, common distributor such as Channel Master, etc? -- thanks.
2008-08-19, 05:24 PM
We've had another member ask about Crown Rotors before. See Posts #124 -> 127
2008-08-19, 10:48 PM
Thanks, Stampeder for your direction. It helped.
Through another well-known site I also found that an old Radio Shack 150-1225 model may be the equivalent (w/parts explosion detail).
I managed to pair the controller with my existing rotor and it all works. I don't think there will be any real need to have the cover or position indicator present if I 'stopwatch' the on/off times on reverse/forward -- to avoid coax wrap around. This should give me an idea of whether this homemade antenna (thanks to the DHC antenna thread for a design) will bring in any tantalizing channels.
If it proves successful then I can go ahead and purchase the full meal deal. We even got an okay from our local district to stick up a tower if we so wish.
2008-08-20, 01:39 AM
Most rotors have a brake point to prevent wrap around. If yours has one you probably would want to have the brake point aimed anywhere in the direction between Cowichan or Sooke so that continuous transits between SeaTac and Vancouver can be done. Glad that you can put up a tower too! :)
2008-08-21, 11:19 AM
Managed to be a bit ahead of you Stampeder, thanks. It does have a brake stop and I did manually scan all the available channels with the Pioneer's combined tuners ..seemed like it took forever :rolleyes:
With the homemade antenna on a pole about 10' above ridgeline, we managed to access (noisy) 6,8,10,12 only.
Oddly enough a set of wabbit ears next to the tv gave almost the same results :confused:
Other stations on up the scale seemed to be trying to come in but mostly just noise pops in and out (however it can be explained) ..so those might be a possibility.
Also, an anomaly of 107 -- a Spanish language station came in almost crystal clear (due North).
Methinks there may be too much LOS stuff to overcome to warrant any real cash outlay here. We do have a ton of evergreens surrounding our place and the neighbourhood and our rancher is one of the lowest profiles in the immediate area. We do live up on a plateau and a tower may be able to overcome some problems but not sure we want to raise the hackles of the neighbours ..and perhaps an amendment to our bylaws in the process.
I did manage to do a search on TVFool and it says more results are (theoretically) available at my Long & Lat.
I think b4 getting too carried away, finding someone with FSM and SA meters who is willing to do some indepth testing might be a better path to continue with.
2008-08-21, 12:44 PM
Good that you were able to test. As for that channel 107 issue, if it was an analogue channel it is likely that someone in your area has signal leakage happening from their cable coax or from where their satellite box might be feeding into their TV. Signal leakage could be causing the weak signals on all the other stations you saw. Just a guess. Also when you scanned did you TV offer you a choice between CATV and Antenna (you'd want the latter)?
2008-08-21, 03:10 PM
Yes, the tv has 2 ant. inputs (with its 3 tuners - dig,ana,qam): 1 input for digital/analog combo, 1 for just analog. I used the ant.1 combo position to capture both digital and/or analog.
For curiosity sakes, here's a couple of pics I took of the temp hookup:
Homemade antenna is 17"x30" similar to the CM4221 with a 300~75 balum attached. A 100' coil of uncut standard single shielded rg6 coax ($ store) was run down to the tv.
Hmm.. I wonder if tinfoil will make a better reflector than the galvanized mesh used?
2008-08-22, 01:39 AM
Definitely don't use foil or solid metal or the wind will blow it down! ;) Electronically a mesh is essentially the same anyways.
2008-08-22, 02:47 PM
CSaanich, I agree with stampeder and channel 107 doesn't make any sense. If your TV is setup correctly the highest possible channel should be 69 (82 if it is a very old TV). It sounds to me it is set up for cable and not an antenna.
2008-08-23, 03:57 PM
No, it was set to antenna "A" - Air. But, Ant A has both NTSC and ASTC tuners and I just kept changing channels -- while rotating the antenna each at 360degrees -- and testing the reception at each until the tv reached 125, and then it went back to 2.
Interestingly there were some upper channels that had subs attached to them (ie: 57.003) -- nothing on them though.
2008-08-23, 09:28 PM
Very strange that Antenna had 125 channels since the channel range is 2 to 69.
2008-08-25, 12:51 PM
CSaanich, can you tell me the make and model of the TV? I will try to find the owners manual to see if that clarifies things.
2008-08-25, 11:22 PM
Anyone know if there are any consumer automated rotator/controller combos that will completely pair with a tv as its channels are selected (how does one make the antenna, rotator and tv all sync together while remembering the antenna positions)?
2008-08-26, 12:28 AM
Sure.. it's a Pioneer Elite Pro-110. The manual's not that precise about tuning (OTA).
I tried using the tv's Channel auto preset function as there appears not to be any way of manually adding digital (ie, 13.001) channels into the tuner (only analog). So, each time the antenna is fractionally rotated, I have to do the auto preset again -- what a pain and waste of time.
But, today I set the antenna to rotate away and while at the same time initializing the tv's auto preset function. The tv did manage to select more operating channels (both analog and digital) but still, each attempt at this exercise provided different preset results and again couldn't add any channels from another scan that were missed on the latest one ..hope that made sense :confused:
2008-08-26, 08:13 AM
I think Channel Master makes one that will move the antenna automatically depending on what channel is selected. How it does it I have no clue.
2008-08-26, 01:01 PM
Yep, both Channel Master and Delhi offer rotor controllers that use IR remote controls, so if you have a Harmony Remote you can program it to send the channel changing commands to both the TV and the rotor controller simultaneously. Your TV will go to the new channel, and within 5 to 30 seconds your antenna aim will go to the correct azimuth.