[pvrusb2] (no subject)

[Roger]

> On Sun, Apr 21, 2019 at 08:19:31PM +0000, Gary Buhrmaster wrote:
>On Sun, Apr 21, 2019 at 9:27 AM Jan Ceuleers <jan.ceuleers at computer.org> wrote:
>
>> The audio defect is a clearly audible repetitive "whistling" noise, with
>> a periodicity of about 1 second. This noise is not present on the audio
>> signal that goes into the PVR.
>
>Just on principal, check the power supplies
>(swap between the units that work and one
>of the STB ones).  And also check for ground
>loops between the PC, the PVR and the
>STB, which can result in all sorts of audio
>artifacts (just go over the the audiophile
>forums and discuss ground issues and
>whines and whistles).

I agree with Gary here concerning noise.

I purchased a Winegard TV preamplifier, for which are only encased in plastic.  
The other TV preamplifier I had at the time, a Channel Master encased in metal 
housing.  Soon after purchasing/installing the plastic Winegard TV preamplifier 
on one of my array of outdoor TV/FM antennas, I encountered significant noise 
over the radio frequency spectrum heard on my ham/shortwave radios; a 
buzzing/whining sound.  After a significant repetitive process of elimination 
of switching-off house circuits/breakers, I finally found the plastic Winegard 
TV preamplifier to be the culprit, and subsequently/immediately replaced with 
the likely better metal encased Channel Master preamplifiers.

Rule of thumb, anything encased in plastic (or unsheilded) can become a noise 
or interference problem.

Can also grab an assortment of ferrite cable clips, 5mm & 9mm, for prancing 
around and clamping to any cable ends (whether RG6, power, audio cable, ...) 
until you find the source. Sort of futile, but will minimize noise on some 
cables due to poor SNR manufacturing standards of products, and with hopes the 
ferrite clips may eventually find the source.

Try using a (sensitive) shortwave or AM radio for finding any RF noise sources, 
but sounds more likely your noise source maybe more inline, or power 
source/feed.  I've also seen high-end or pricey computer power supplies (PSU) 
cause noise, of which Corsair readily replaced.


-- 
Roger
http://rogerx.sdf.org/
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