Hello everybody! Been an avsforum lurker for quite a while - what a tremendous resource! Maybe you guys can help shed some light on something for me......
I recently purchased a new Panasonic ST50 Plasma to replace my LG LCD that was about 5 years old. I had been using a Clearstream4 outdoor antenna mounted at the tip of my roof (about 20' up) for OTA reception, and it has worked pretty well. However, upon hooking up my new Panasonic, many of the OTA stations that I was able to receive before solidly were not breaking up quite a bit, and I even lost a station altogether. I did some research and found that this a popular complaint regarding the integrated ATSC tuner in the Panasonic's, that the tuner was not as solid as some of the others out there. For reference, most of my station towers are about 54 miles away, according to TV Fool.
So I was demoralized - awesome new TV, suddenly only good for watching Blu-Ray and playing PS3. However, I remembered having a conversation with a guy I worked with about his OTA setup, and he said that he was using some little antenna he bought at home depot for $50 and was getting all of the channels that I was getting, plus a few more on VHF. After doing a little bit of research, we determined that it was the GE Futura. I honestly thought that he was exaggerating somewhat on the number of stations that he was picking up, so I didn't think much more of it until my new set not picking up all of the stations I wanted. So I decided to run to home depot and pick up one of these antennas and give it a shot, just to see what happens. I figured it would be easy to return it once it failed miserably vs. the Clearstream4. Before going up on the roof again, I just decided to hook it up in my attic first just to see what it would to do, so I just threw it over a rafter and did a channel scan. To my amazement, it picked ALL of the stations that the CS4 did, PLUS 3 more! I immediately decided to go up on the roof and mount it in the same position as the CS4 and test it - it immediately picked up 3 MORE channels, so now 6 more altogether. Now, after some slight repositioning, I get ALL of the channels in solid signal quality - none of them are breaking up now.
This is no fluke. I told my buddy who lives a few hours away in a different market about it, so he decided to pick one up from Home Depot as well. He also had a CS4. After hooking it up, he got 5 new channels, mainly due to now having the ability to receive VHF. He was still picking up all of his old UHF stations also.
I want to know how this is possible...... everything that I've come to know about OTA reception says that the more metal you have in the sky, and the higher, the better off you are. I haven't taken the GE Futrura apart, but there can't be much in there in the way of reception elements for both UHF and VHF! I know that it has to be in the amplification... but I just don't understand how this could make that much of a difference. I did not have a pre-amp on my CS4 because the RG6 run from the antenna to the amplified distribution amp is only about 20ft, so I didn't figure that I needed one.
Can anybody shed any light on this?
The amplifier is likely the difference. If you installed a decent pre-amp on the C4, it would probably get those additional stations.
There are several different variables, so you're trying to compare apples vs bananas vs cumquats:
a. CS4 doesn't even TRY to provide coverage in Hi-VHF Band, whilst GE Futura INDOOR Model 24746 has a
pull-out WHIP to at least TRY to squeeze out a bit of Gain for VHF (OUTDOOR Model 24769 may be internal):
Compare to the SIMILAR (but NO Whip) Philips MANT940: http://www.walb.com/Global/story.asp?S=8346127
b. "GE Futura" is a trademark name, with a variety of different Models. INDOOR Model 24746 does NOT
APPEAR to have an internal Amplifier....until you read the User Manual and learn that, just like the OUTDOOR
Model 24769, they BOTH have an internal 20 dB Gain Amplifier :
Note that when you hover over the picture of the Indoor Model, the popup claims VHF/FM/UHF coverage.
If the "GE Futura" antennas you have been using include an Amplifier, there is probably an improvement
in UHF sensitivity...which "typically" can be about 10 dB (depending on coax type/length, RF Splitters, et al).
Don't know the details, but the outdoor version of the GE Futura that sells for $49.00 is indeed a good performing antenna for that type of flat panel design. Apparently has a good amp also. Worked better with weak signals than the similar Radioshack version and the Phillips version sold at Walmart. Tried all 3 to help a neighbor who wanted a minimal antenna and got best results with that Home Depot version. So for that type of antenna, the GE model does seem to be the best. But overall, there are certainly much better real antennas out there, especially when used with a preamp when necessary. But those flat panel types can certainly do the trick in the right situations.
I'm shocked the the amplifier (pre-amp?) can make that much of the difference.... the reason I didn't get a pre-amp for my CS4 was because I was actually worried about signal overload, and my coax run was very short. Now I'm curious as to how well the CS4 would have done with a pre-amp!
I told yet another friend about my project, and pointed him to the Monoprice antenna of this type, which has gotten some pretty stellar reviews. I almost want to buy one just to take it apart and see what's going on inside!
You should enter your location into www.tvfool.com
and copy/paste the RESULTS URL (webpage) into post.
Add the Antenna Gain to the RX (dBm) levels to determine the signals levels presented to a Preamp.
Then compare to the "Spurious Free Dynamic Range" (SFDR) signal levels calculated in my DTV Preamp
Signal Overload Calculator spread sheet (see link in my signature line)...note that some Low Gain Preamps
have much higher resistance to overload than high Gain Preamps (e.g. CM7777)....which are intended
for use in RURAL locations....NOT in typical Urban location....
It would help if you were able to identify the specific stations that are on the "difference" list. There are a number of factors involved including operating channel of the area stations as well as distance and bearing and the aiming direction of the C4
The C4 is a moderately directional UHF antenna and isn't a particular good match for your area due to the combination of factors. A small, U/V combo would certainly be a better match. A specific recommendation depends on whether or not WABW is on your "must have" list.
Signals aren't strong enough to worry about overloading a Preamp....even a high-gain Preamp.
UHF Antenna should readily pick up CBS (2), FOX, NBC & ABC without the need to rotate the antenna.
SEPARATE Hi-VHF Antenna will readily pick up PBS on Ch8 (8.1), without the need to rotate the
antenna....but needs to be pointed towards 70-deg (TN) rather than 243-deg (TN) for UHF Antenna.
So simplest system would be current C4 and add a Hi-VHF Antenna, such as Antennacraft Y5-7-13.
[And you might even get lucky and receive other PBS on Ch6 (14.1).....maybe.....]
FYI: A-D EU385 and Radio Shack 15-2586 VHF/UHF Combiners are DCPASS to a UHF Preamp,
whereas UVSJ devices from Macom-Pico and Hollands are DCPASS only on VHF side (Really!!!!).
Strange....amplifying VHF Band is NOT recommended due to FM overload issues.
If you want to receive ION network Ch24 (21.1), then you'll need a ROTATOR...and a Preamp....
and A-D C4 may not have enough Gain to make it happen.....
DUPLICATE Fox on Ch12 (31.1) and DUPLICATE NBC on Ch10 (10.1) may or may not come in
on the VHF Antenna.....until you add a ROTATOR....but might not be worth the hassle.....
If you just HAVE to have (may or may not be Duplicate) PBS on Ch6 (14.1), then you'll need to
upgrade to a BIG Ch2-13 VHF Antenna on a ROTATOR....or a BIG VHF/UHF Combo Antennas.