I was talking to Michael Krufky the other day on the v4l irc channel and he mentioned a major problem when he got his first tuner card. He said his apartment building was split so many times that the signal he was receiving was really weak. He could only receive fox. He mentioned that he got a drop amp to boost the signal. As soon as he got that he was able to receive all the channels he couldn't receive before without the amp.
<br><br>He said that I should get an amp after he saw the signal fluctuation on especially 543 Mhz but he said that it may or may not fix the problem. I decided to get a 4-way PCT Drop Amp on eBay similar to the 8-way drop amp that he has but since it is just 4-way, it is more powerful than an 8-way. I haven't received it yet but I should be able to try it out soon to see if it fixes my problem.
<br><br>In the mean time, I remembered that I was splitting the line with my other MyHD tuner card with what I thought was a high quality "gold plated" 5-900 Mhz passive 2-way splitter. I decided to remove the MyHD card from the equation and plug my the card in my Linux box (Dvico Fusion HDTV5) directly into the wall to see if it fixes the problem. Initially I saw no change in the signal strength and I still could not tune the atsc channels I knew were on 543 Mhz. After about 15 minutes, I tried azap again on that frequency and I was suddenly getting a signal lock on that frequency which I never got before. It was locking but it still looked like it was just strong enough to get a unbroken lock on the frequency when I saw the signal strength as straight cxxx. It was holding for a while so I was finally able to map all the channels with dvbscan that I could never do before.
<br><br>The next day it was still working but when I checked it again at the end of the day, it had reverted back to the old fluctuation in the signal despite removing the MyHD card and the splitter. I have at times been able to lock onto it again and gotten a weak lock but not for long and as I write this, I am experiencing fluctuations on that frequency again and am unable to watch any of the channels on that frequency.
<br><br>I report my findings here again after I test the amp which will give me an 8db bump on the port. If it fixes the problem with tuning that frequency on my Dvico card, I'll test the amp with my MyHD card to make sure that additional tuner cards don't exacerbate the problem with tuning on those frequencies.
<br><br><br><br><div><span class="gmail_quote">On 2/18/07, <b class="gmail_sendername">Matthew T. Russotto</b> <<a href="mailto:firstname.lastname@example.org">email@example.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Unfortunately, I don't think that's a driver bug but a hardware<br>limitation. My PCHDTV 5500 card seems to be less sensitive to signal<br>or more sensitive to interference on CATV 76 and 77 (537 and 543 Mhz).<br>
I was able to fix my problem by replacing a set of two-way splitters<br>with a higher-quality 3-way splitter and putting the problem card on<br>the 4db drop leg. Having another card (a KWORLD ATSC 110) in the<br>system seems to exacerbate the problem.
<br><br>If there's a way to remedy the issue in software I'd expect it to be a<br>tuner parameter; are you also using a PCHDTV 5500 or other card with LG<br>tuner?<br><br><br>_______________________________________________
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