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Old April 7th 18, 12:44 PM posted to
Brian Gaff
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Posts: 7,250
Default Has Com78 National (Ch56) from Rowridge changed?

In the old days of Analogue one of my jobs was to test tv tuners coming in
from Mullard and Telefunken that our factory used.
The gain and noise over the wide bandwidth was really variable on many of
these tuners, often batch dependent. I often wonder how we are doing on this
front with modern sdr systems now in use. Seems to me that unless there is a
very good preselector, the input can be overloaded by anything anywhere near
the actual frequency, making everything non linear and full of cross mod
problems. I remember playing with onne of these el cheapo devices made in
china. It was pointless using it as a scanner near any large transmitter.

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"Scott" wrote in message
On Sat, 7 Apr 2018 11:48:35 +0100, Jeff Layman

A couple of weeks ago I posted that for some reason my Panasonic PVR
could still pick up Com78 on CH56 using the Group A 18-element loft
aerial. Under the same conditions, the Panasonic TV couldn't see Com78.

Yesterday (before retuning to get the 4 April changes), I had a look at
the Com78 signal strength and quality on the PVR's setup menu. It was
interesting that the signal strength bar was showing 6-7, and quality
was 5 or 6 with a yellow bar. The picture and sound were normal on
CBeebies HD and BBC4 HD. I just retuned, and now Com78 is down in
quality. CBeebies is still showing 6 or 7 for strength, but quality is
at 1 in red (sometimes it gets to 2). Strangely, most of the time the
picture and sound are fine.

I still find it amazing that the PVR can deal with a signal with as poor
a quality as this, which the TV can't even see!

My friend has reception problems (probably fault of the communal
aerial), which she can normally resolve by using the Humax box.