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#1
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Hi All,
I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. |
#2
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In message , amdx
writes Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Despite your long 170ft drop cable, were you getting good analogue signals before the change to digital? If so, it could be that something is not right. Normally, even if you have had only fairly mediocre analogues, the digitals are good. Otherwise.... It sounds like your signals are just too weak. As things are, and if you can, the obvious fix would be to overcome the substantial loss of the 170ft drop cable by fitting an amplifier at or near the utility post (not at your end), and power it with low voltage via the coax from your end (ie similar to a line-powered masthead antenna amplifier). However, you would need to consult with the cable company to see if they were OK with letting you do this. It could be that they might be able advise you on the most suitable amplifier to use. It's not rocket science, but you have to be a little careful not to break any of their rules and generally do anything they don't approve of. -- Ian |
#3
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On 2/8/2012 2:17 PM, Ian Jackson wrote:
In message , amdx writes Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Despite your long 170ft drop cable, were you getting good analogue signals before the change to digital? If so, it could be that something is not right. Normally, even if you have had only fairly mediocre analogues, the digitals are good. But, analog can be snowy but very watchable, digital an be pixalated and stuttering without no sound or often no picture at all. Otherwise.... It sounds like your signals are just too weak. As things are, and if you can, the obvious fix would be to overcome the substantial loss of the 170ft drop cable by fitting an amplifier at or near the utility post (not at your end), and power it with low voltage via the coax from your end (ie similar to a line-powered masthead antenna amplifier). However, you would need to consult with the cable company to see if they were OK with letting you do this. It could be that they might be able advise you on the most suitable amplifier to use. It's not rocket science, but you have to be a little careful not to break any of their rules and generally do anything they don't approve of. I had not thought about a coax powered amp, Thanks. Mikek |
#4
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In message , amdx
writes On 2/8/2012 2:17 PM, Ian Jackson wrote: In message , amdx writes Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Despite your long 170ft drop cable, were you getting good analogue signals before the change to digital? If so, it could be that something is not right. Normally, even if you have had only fairly mediocre analogues, the digitals are good. But, analog can be snowy but very watchable, digital an be pixalated and stuttering without no sound or often no picture at all. You are quite correct. However, digital is generally capable of working to lower signal levels than analogue. It's amazing how rubbishy digital signals can be, yet still give perfect pictures - but don't expect miracles! Otherwise.... It sounds like your signals are just too weak. As things are, and if you can, the obvious fix would be to overcome the substantial loss of the 170ft drop cable by fitting an amplifier at or near the utility post (not at your end), and power it with low voltage via the coax from your end (ie similar to a line-powered masthead antenna amplifier). However, you would need to consult with the cable company to see if they were OK with letting you do this. It could be that they might be able advise you on the most suitable amplifier to use. It's not rocket science, but you have to be a little careful not to break any of their rules and generally do anything they don't approve of. I had not thought about a coax powered amp, Thanks. Mikek I see that several others have also suggested a coax-powered amplifier. [If the cable company can't give you more signal level, it's the only solution.] As suggested, they should be able to provide a suitable amplifier and power unit - or at least advise you what to use. -- Ian |
#5
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On Wed, 8 Feb 2012 20:17:11 +0000, Ian Jackson
wrote: In message , amdx writes Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Despite your long 170ft drop cable, were you getting good analogue signals before the change to digital? If so, it could be that something is not right. Normally, even if you have had only fairly mediocre analogues, the digitals are good. Otherwise.... It sounds like your signals are just too weak. As things are, and if you can, the obvious fix would be to overcome the substantial loss of the 170ft drop cable by fitting an amplifier at or near the utility post (not at your end), and power it with low voltage via the coax from your end (ie similar to a line-powered masthead antenna amplifier). However, you would need to consult with the cable company to see if they were OK with letting you do this. It could be that they might be able advise you on the most suitable amplifier to use. It's not rocket science, but you have to be a little careful not to break any of their rules and generally do anything they don't approve of. The cable company probably has amplifiers that can be powered over the cable run. If not, those amps can be found on ebay. Be sure to get a bidirectional amplifier because some systems send the control signals back up the cable to the cable company (Comcast in the southeastern US, for example.) John |
#6
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On Feb 8, 2:00*pm, amdx wrote:
Hi All, I'm on a boat, about 170ft from the utility post. That's about 10dB loss at midband for RG6. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap.. That was just a 3dB boost. * That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. * *I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? Really? There are such things a power inserters and compatible drop amps that allow you to power the amplifier over the cable from the user end. For RG6 18ga stranded that is about 0.6V loss at 250mA and therefore doable, I would run two cables if there was a way to make it increase signal strength. Forget it. * Getting anymore from the cable company is not an option. * *Any ideas to get a better signal? * * * * * * * * Mikek Use a 15dB gain drop amp with power inserter, but that's just a guess. Would help if you actually knew signal levels like what the receiver requires for optimum reception and what the cable co sources. Putting the amplifier at source gives you a typical system noise figure of 3dB, but putting it at your end limits your NF to 10dB minimum from the start. |
#7
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On 2/8/2012 2:36 PM, Fred Bloggs wrote:
On Feb 8, 2:00 pm, wrote: Hi All, I'm on a boat, about 170ft from the utility post. That's about 10dB loss at midband for RG6. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That was just a 3dB boost. But that 3bd did get me a more consistent picture. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. |
#8
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On Feb 8, 4:36*pm, Fred Bloggs
wrote: On Feb 8, 2:00*pm, amdx wrote: Those amps with power inserters, available from Radio Shack for around $40-50 as I recall, do work well, HOWEVER, I have had 2 of them burn out on me. They do run rather hot. But when they work, they usually do the trick. You power it from the TV end and the inline amp has a blocking cap so you don't put DC on the whole system. Theoreticaslly, that is what you need. I think you should put one amp every 50 feet but that may not be possible for you. Use a 15dB gain drop amp with power inserter, but that's just a guess. Would help if you actually knew signal levels like what the receiver requires for optimum reception and what the cable co sources. Putting the amplifier at source gives you a typical system noise figure of 3dB, but putting it at your end limits your NF to 10dB minimum from the start. |
#9
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![]() AI4QJ wrote: On Feb 8, 4:36 pm, Fred Bloggs wrote: On Feb 8, 2:00 pm, amdx wrote: Those amps with power inserters, available from Radio Shack for around $40-50 as I recall, do work well, HOWEVER, I have had 2 of them burn out on me. They do run rather hot. But when they work, they usually do the trick. You power it from the TV end and the inline amp has a blocking cap so you don't put DC on the whole system. Theoreticaslly, that is what you need. I think you should put one amp every 50 feet but that may not be possible for you. What kind of coax has 10 dB loss per 50 feet, and at what frequency? Those RS amps have no equalization, so the low channels would overlaod the front end, and the high channels would still be snowy if you need more than one or two.. -- You can't have a sense of humor, if you have no sense. |
#10
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In article ,
amdx wrote: I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Adding an amp at the cable box isn't all that likely to work... you can try it, but don't get your hopes up. Unless the amp has a significantly lower "noise figure" than the RF front end in the cable box, all you'll be doing is adding noise... the desired signal will be stronger, but the noise will be stronger yet. Something you could do, is add a single-port RF amplifier right at the utility post splitter, where your tap comes off of the feed. You can buy amplifiers of this sort which are designed to receive "phantom power" through the coax cable... you'd install a "power injector" at your boat, which feeds a DC voltage up the coax to the amplifier. This is probably your best bet: - It would amplify the signal before it's attenuated by the 170-foot cable run. - It won't require a power supply at the post... just at your boat, where you already have power. - It shouldn't interfere with the other taps on the splitter, even when the amplifier is not receiving power from your boat. You'd be looking for an "antenna mast" type of preamplifier. The Channel Master 0068DSB or 7777, Winegard AP-8700 or AP-8275 or HDP-269, AntennaCraft 10G212, or one of the Blonder Tongue Galaxy III models might do the job for you. You'll probably want a "75 ohm in, 75 ohm out" model, which would connect directly to the 75-ohm coax. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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