[mythtv-users] announce: script for locating QAM channels

[Brian Wood]

On Mar 5, 2006, at 8:40 AM, Jeremy McDermond wrote:

> On Mar 5, 2006, at 5:32 AM, Brian Wood wrote:
>
>> I'm a firm believer in using high-quality power supplies. A lot of
>> problems can be traced to cheap ones (especially the ones in the $50
>> cases with PS included). The PS is usually the first place a builder
>> will skimp in order to save $$$.
>>
>> As I mentioned previously, I've had this problem with two different
>> machines, the first had a Thermaltake 560-watt PSU, and the second
>> was a stock Dell machine, not great, but probably a serviceable PSU.
>>
>> Good thought though. I wonder how much power capture cards in general
>> draw. When MythTV systems start to get 3 or 4 of them how much power
>> are we talking about ?
>>
>> I wonder if a lot of the strange, intermittent and unrepeatable
>> problems we see reported here might be related to power problems.
>
> I'm not sure if it's necessarily having enough power, but having
> clean power.  Having interference from a poorly shielded power
> supply, or having dirty power being provided to the card could wreck
> some serious havoc with the RF side of the card.

Agreed, I've seen "600 watt" power supplies for $20, I think they  
were made by "SpikeMaster" :-)

Good quality capacitors and inductors are expensive, colored LEDs and  
fancy fans are not.

You get what you pay for generally, certainly no more than that.  
Thermaltake, PC Power and Cooling and Antec seem to make decent  
units. You can tell a lot just from the weight, a 500-watt unit  
should not weigh less than your mouse.

PC P&C makes a 1000 watt unit, 1100 watt peak, but it's something  
over $400 :-(
>
>
>> So it sounds like the reported BER is meaningless ??
>>
>> I'll try connecting my card further upstream to see if this makes a
>> difference. I had been assuming that a zero BER meant I had
>> sufficient signal
>
> According to http://www.penlug.org/twiki/bin/view/Main/
> DigitalTelevisionDVB, the BER is meaningless on an HD-3000 card:
>
> Note that neither the pcHDTV HD-2000 nor the HD-3000 card support the
> FE_READ_BER ioctl, so the ber reported by azap is undefined. It's
> usually 00000000 for the HD-3000 card, and something like FFFFFFF3
> for the HD-2000 card.
>

Ah-Ha. It was interesting that I had "perfect" reception on all  
channels. "If it seems too good to be true ..."

I now suspect a lot of my troubles may just be related to low signal.

Thanks for the pointer.