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Old 8-Sep-2015, 2:05 PM   #1
bob66542
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Newbie in KS with questions, please read

brand new to your forum, your tv signal analysis is very helpful. I am in S.E. Topeka and am trying to pick up Kansas city stations. I currently have an antenna in my attic, and when pointed toward KC can get 2 stations there, sometimes. I plan to try temporarily mounting on the roof of my garage to see if I can get more, and better reception. question #1- what is the maximum length allowable for my coax cable? what I have is RG6-U. #2 can I mount 2 antennas, one aimed at KC, one aimed N.W. towards all the Topeka towers, and connect them with a splitter? #3 Most of my TV's are older, analog sets- I understand there are digital to analog converters available, do those of you IN THE KNOW have any recomendations for me? reasonably priced? And is it possible to record with old VHS VCR's with any of them, or will I have to buy a DVR and connect it to my 1 digital TV? Thanks, Bob
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Old 9-Sep-2015, 6:20 PM   #2
rabbit73
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Welcome, Bob:

You would get more answers if you posted your question here:
Help With Reception
http://forum.tvfool.com/forumdisplay.php?f=7

Quote:
your tv signal analysis is very helpful.
It would help us to help you if we could see the signal analysis for your location; go here and enter your exact address or coordinates (which will not show) and give us the link to the report:
http://www.tvfool.com/index.php?opti...pper&Itemid=29

Quote:
I currently have an antenna in my attic, and when pointed toward KC can get 2 stations there, sometimes.
What antenna?

That is what would be expected. The attic location causes a signal loss and the KC signals are weak and of poor quality because of terrain interference. There might also be trees or other buildings in the way. Are there trees or other buildings in the way?
Quote:
#1- what is the maximum length allowable for my coax cable?
Too soon to tell; what length do you need?
Quote:
#2 can I mount 2 antennas, one aimed at KC, one aimed N.W. towards all the Topeka towers, and connect them with a splitter?
Using a splitter in reverse as a combiner doesn't usually work well because when the same signals arrive at the combining point, they interfere with each other if they don't arrive in phase. You would need a rotator or two antennas with an A/B switch.

Quote:
I plan to try temporarily mounting on the roof of my garage to see if I can get more,
You could have two systems. One in the attic for the strong local signals, and one on the roof with a preamp for KC.

It might be possible to remove the reflector from an antenna to make it bi-directional but that probably wouldn't be satisfactory because the KC signals need a preamp, but the local signals would overload a preamp.
Quote:
I understand there are digital to analog converters available, do those of you IN THE KNOW have any recomendations for me? reasonably priced?
There are still some available, that are reasonable, new and on ebay.

Quote:
And is it possible to record with old VHS VCR's with any of them,
Yes, you would use the audio/video output of the converter box into the VCR audio/video input. Or you could do ant out of converter box to ant input of VCR and VCR to analog TV ant input.

If you lived at SE 31st ST and SE California Ave just inside Kansas Turnpike 470, your report would look like this:
http://www.tvfool.com/?option=com_wr...8e032cdaca8e9b
The turnpike traffic might interfere with the KC signals.

If you lived at SE 32nd St and SE Granger St outside 470 near Lake Shawnee Marina, your report would look like this:
http://www.tvfool.com/?option=com_wr...8e03b8820e1214
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Last edited by rabbit73; 9-Sep-2015 at 10:08 PM.
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Old 10-Sep-2015, 4:46 PM   #3
bob66542
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Rabbit 73 thanks for your reply. Being a computer idiot, I have been unable to attach my signal alalysis to this reply. I appreciate your explanation about using a splitter to connect 2 antennas. I am still confused about using an old VHS VCR to record using a converter box, as there is no way to input a digital channel like 13.2 into the vcr, which will not take a decimal point. would it be done thru the converter? re; trees/buildings- there is a tree directly east of my house but if I attach to my garage, north of the house I can get past the tree , which I will try this weekend. the cable from antenna to tv in the house would be approx 70'
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Old 10-Sep-2015, 7:31 PM   #4
rabbit73
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Quote:
Being a computer idiot, I have been unable to attach my signal alalysis to this reply.
Go here to get your report:
http://www.tvfool.com/index.php?opti...pper&Itemid=29

Near the top of the report you will see a link in bold type that looks like this:



Copy and paste (don't retype each character) just the last part like this, and we will turn it into an active link:
?option=com_wrapper&Itemid=29&q=id%3d8e032cdaca8e9b

Quote:
I am still confused about using an old VHS VCR to record using a converter box, as there is no way to input a digital channel like 13.2 into the vcr, which will not take a decimal point. would it be done thru the converter?
Yes, the antenna sends the digital signal to the converter box, and the converter box sends an analog signal to the VCR.
Antenna > coax > converter box > VCR > TV

Quote:
I will try this weekend. the cable from antenna to tv in the house would be approx 70'
For the test, just connect the antenna to the digital TV with the antenna aimed at 270 degrees magnetic (or whatever azimuth is on your real report ) with a pocket compass for your strongest channels, and scan for channels.

Then try aiming your antenna to the east and rescan. Those signals will probably be too weak without a preamp, but try it anyway.

Please tell us about your antenna.

Do you get your local channels with the antenna in the attic?

If your antenna will be outside the coax shield should be grounded with a grounding block that is connected to the house electrical system ground with 10 gauge copper wire for electrical safety and to reject interference. For further compliance with the electrical code (NEC), the mast should also be grounded in a similar manner to drain any buildup of static charge, but the system will not survive a direct strike.
Attached Images
File Type: gif NEC Grounding.gif (16.5 KB, 24183 views)
File Type: jpg TVFOOL Link4.JPG (21.3 KB, 691 views)
__________________
If you can not measure it, you can not improve it.
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http://www.megalithia.com/elect/aeri...ttpoorman.html

Last edited by rabbit73; 11-Sep-2015 at 12:52 AM.
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Old 11-Sep-2015, 4:17 PM   #5
bob66542
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newbie in KS with signal analysis

http://www.tvfool.com/?option=com_wr...8e03ae22567f03
Rabbit 73, here is my signal anaylisis. thanks for telling me what I had to do, I have a friend here in the office that taught me how to copy and paste.
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Old 11-Sep-2015, 5:14 PM   #6
bob66542
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My antenna is a GE 34792. It works great in my attic and gets my local topeka channels, and when I pointed it towards KC, I got a couple of KC channels, but not constantly. I should be able to safely put up a temporary mast without the grounding to test for reception as long as it is clear, hadnt I ? I WON'T leave it without proper grounding.
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Old 11-Sep-2015, 7:19 PM   #7
rabbit73
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Thanks for the TVFOOL report. That puts you, as your report says, further out from the center of Topeka in Tecumseh near Watson. Your Topeka signals are about 5 dB weaker than my first estimate and so are your KC signals, with about 50 dB difference between them.

Thanks for the antenna info. That GE antenna is good for strong signal areas, but doesn't have much gain for the weaker KC signals.

Quote:
I should be able to safely put up a temporary mast without the grounding to test for reception as long as it is clear, hadnt I ? I WON'T leave it without proper grounding.
As far as avoiding storms, that's good. But as far as electrical safety goes, remember that the coax from the antenna is connected to AC operated equipment. All AC operated equipment has leakage current even when it is operating properly. Just because you can't feel it doesn't mean it isn't there. If the equipment has a 3-wire power cord that is connected to a properly wired 3-wire receptacle, it will drain the leakge current to ground, but many TVs only have a 2-wire cord.

If the equipment became defective, there might be a shock hazard. If you feel a tingle from the coax shield, you must ground the coax with a grounding block.
http://www.digitalhome.ca/forum/81-o...ml#post1457594
http://www.digitalhome.ca/forum/81-o...ml#post1457668

When you make the test with the GE antenna outside with the antenna aimed at Topeka, the local signals will be stronger, but probably will not overload the tuner. When you aim the antenna toward KC the antenna might do a little better than inside and still receive the Topeka signals.

The problem is that you need an antenna with more gain for KC (which would be more directional), and maybe a preamp too, but a preamp might be overloaded by the Topeka signals. Maybe you will be able to find a happy medium, but I think the best reception would be with two antennas and a switch.

KTWU has a Noise Margin of 62.6 dB even before adding antenna gain or preamp gain, which puts it in the Possible Overload category. KSHB has a NM of 6.1 dB, Weak.



Interpreting Noise Margin in the TV Fool Report
http://www.aa6g.org/DTV/Reception/tvfool_nm.html
__________________
If you can not measure it, you can not improve it.
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http://www.megalithia.com/elect/aeri...ttpoorman.html

Last edited by rabbit73; 11-Sep-2015 at 8:07 PM.
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Old 14-Sep-2015, 4:11 PM   #8
bob66542
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re: newbie

I put up a temporary pole, 20' was suprised to find the reception was no different than with the antenna in the attic, so thats where it will go for now. do you have any recomendations for a better antenna? For the time being, the 26 channels I can get is good enough for me to make the decision to get rid of cox cable, which goes full digital on oct.6 here, and I would have to rent a convertor for each tv I have from them for a monthly $2 each on top of their already outragous prices. My next question concerns multiple TVs- can I split off the antenna multiple times, as can be done with cable TV? I havent tried yet, because I only have 1 modern TV, and havent yet bought a digital to analog converter. also- should I be posting these questions in another part of the forum? Thanks, Bob
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Old 14-Sep-2015, 10:41 PM   #9
rabbit73
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Thank you for making the test. If you are happy with the GE antenna in the attic, that's where it should be. And you don't have to worry about grounding the mast.
Quote:
can I split off the antenna multiple times, as can be done with cable TV?
If you add another TV or converter box, try using a splitter first. If you don't have enough signal for more than one TV, replace the splitter with a distribution amplifier like the Channel Master 3412 for 2 TVs or a 3414 for 3 or 4 TVs.

Don't try to combine antenna and cable signals on the same coax.

Quote:
do you have any recommendations for a better antenna?
If you think you need it, the next step up would be a Winegard HD7694P. If you want to experiment with it you can aim it toward KC. Then you could have two separate antennas, one for Topeka and one for KC, with an A/B switch to change antennas.

An alternative to the switch would be to connect the GE antenna for Topeka to the antenna input of the digital TV, and connect the 7694 antenna for KC to the input of a separate tuner or converter box with its output going to the auxiliary input of the digital TV , to another TV, or to the input of a VCR.
Quote:
also- should I be posting these questions in another part of the forum?
Um, it's kind of too late now for these questions, but you are welcome to post new questions on the Help With Reception thread:
http://forum.tvfool.com/forumdisplay.php?f=7
__________________
If you can not measure it, you can not improve it.
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http://www.megalithia.com/elect/aeri...ttpoorman.html

Last edited by rabbit73; 14-Sep-2015 at 10:54 PM.
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Old 15-Sep-2015, 1:32 PM   #10
bob66542
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Thanks so much for all your help! would there be a distribution amplifier for more tha 4 tv's? we actually have 6 spread out in different rooms/ bedrooms of the house.
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Old 15-Sep-2015, 9:46 PM   #11
bob66542
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Never mind- I see they have a CM 3418. Thanks again for all the help.
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Old 17-Sep-2015, 9:08 PM   #12
bob66542
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are the channelmaster cm3418 and the PCT-MA2-8P the same unit? look exactly the same, but the pct is $29 on amazon and the channelmaster is $51. I do see that in the ad the CM specifically states ac/dc power supply incl. and there is no such statement with the PCT
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