PVR-150, flashing color on one chan only ??

[Dave72]

I finally dug out my old PVR-150 and installed it for GBPVR use. We only get 3 channels OTA here, but this would add some selection to the stuff we watch.
I made a folded dipole for the center of freq range of the available channels. They came in fairly well, but the one channel that the wife really wants was having color problems.. the reds are sorta flashing in and out. So, I cut the antenna down to the exact freq (189 Mhz for channel 9 in this case), and the pic is perfect with no snow .. but the red flickering is still there.

I tried older drivers (yes, used hwclear), tried other apps (Wintv2000 and VLC both flicker the same). Output to my MVP flickers the same as on the pc. I tried another TV on the antenna and it was perfectly fine !

If my PVR150 is bad, wouldnt all channels be doing the same thing ? (isnt colour stuff after the rf/if stage ?).

Could it be something in my pc ? Where the heck would ya start tuning in there ?? This pc only has 2 PCI slots, one has my Nexus, the other has this PVR150. There is nothing on the other 3 pci-e slots and then the video card is in the long pcie slot.

Id get another tuner card, but it seems anything better than a pvr150 is about $160+

[Dave72]

Update..

I should clarify more info now that I have looked into it more..

We actually get 4 channels here. The 2 VHF low band channels are not coming in very well, but I can see some red flickering in one of them, the other is too snowy to tell for sure. We do have 2 VHF high-band channels, but one is french (so I didnt have it programmed in). Now that I look at that other high-band channel, it has no red flickering at all and has a clear pic.. BUT, I see faint diagonal lines in the pic (well, tilted about 15 degrees ?). There appears to be perhaps 30 lines. They go from quite visible and still, to rolling so fast that they pretty much disappear.

So it does appear to be some type of frequency thing, affecting my channel 9 the worst (causing color blooms or whatever), affecting chan 12 somewhat (the rolling bars), and chan 4 a little bit.. perhaps not chan 2 at all ?

I tried setting my FSB up to 210 from 200, no effect. Tried putting my PCIe freq from 100 to 102, no effect.

[Dave72]

OK, now the plot thickens..

I found an old Radio Shack 'TV Converter' that bumps the VHF channel range into the UHF band.

Did a rescan with this unit in place, and now my old VHF-9 shows up at 116 and my old VHF-12 shows up at 119.

But, ch 116 is still flashing funny colours. wtf ??

The rf into the computer is now totally different for that channel.. so it cant be in-case rf issues.. (if it was baseband or all channels , then maybe..). But when I tried another tv before, this channel was fine !

Is it possible that there's something inside this channel's signal band thats causing the PVR-150 to freak out ? (and yet, doesnt affect a normal tv)

[Dave72]

A TV tech told me that perhaps the colour (chroma) part of the signal is weak, and I should try a booster.

Bought a 10db unit. No difference (well, my snowy channels come in better..). The odd flashing colours are still there.

For a test, I swapped in an attenuator. I can make the channel nearly disappear by attenuating it, but still.. those colours flash.

Luckily,with the amplifier, I am able to fine tune the channel about 600khz and the flashing nearly all disappears.

Does it not sound like some type of EMI ?

[mvallevand]

I used to have some awful buzzing and really distorted Red on MuchMusic when they played music. I played around with the frequencies using the software and got it a bit better but never perfect. I figure it was video noise.

Martin