RF modulator or TV problem?

[davidr...@postmaster.co.uk]

A relative has a Vision V40-104 RF modulator feeding two TVs through a
small distribution amplifier. There is nothing else on the RF cable
except the return path for two magic eyes, i.e. AS FAR A I KNOW(!) the
system is _not_ connected to a TV aerial. They use Freesat
exclusively: a PVR in the lounge feeds the lounge TV via HDMI, and the
other two TVs via RF.

Everything worked fine for at least a year.

A few months back, intermittent sound problems appeared on one of the
TVs fed from the modulator. Sound would be fine sometimes, but covered
in hiss/buzz other times. They've tried re-tuning, but it doesn't seem
to help. (I gave instructions over the phone - I assume they were
doing it correctly, but can't be sure).

Recently, most but not all of the time, "no signal" is all that
appears on the other TV. Other times, everything is fine on this TV.
Cannot retune, because the remote is dead. Ordered a new remote.

Any clues as to what might be happening before I visit this relative?
i.e. are both TVs on the blink, is the modulator drifting, or is some
source of interference getting into the (PF100) cable on channel 63?

They are both old analogue-only TVs. The first is probably 25 years
old (Sony, still apparently working well), the second is probably 7
years old (Goodmans, built in DVD, bought from Tesco).

Thanks for any help or advice.
David.

P.S. Didn't go down Freeview route as relative probably can't cope
with re-tunes. Hoped this would be a "set and forget" Freesat system,
and for over a year, that was true.

[Brian Gaff]

My take is interference first and the modulator second.
Brian

--
From the Bed of Brian Gaff.
The email is valid as bri...@blueyonder.co.uk
Blind user.
<davidr...@postmaster.co.uk> wrote in message
news:3ec3be3f-98fb-4c5f...@fw24g2000vbb.googlegroups.com...

[NY]

"Brian Gaff" <bri...@blueyonder.co.uk> wrote in message
news:kfgc65$3io$1...@dont-email.me...

I wonder if there have been any changes to the UHF channels used by Freeview
in that area which means that something is interfering with the UHF 63 that
your modulator is generating.

[hwh]

On 2/13/13 4:26 PM, davidr...@postmaster.co.uk wrote:
> A relative has a Vision V40-104 RF modulator feeding two TVs through a
> small distribution amplifier. There is nothing else on the RF cable
> except the return path for two magic eyes, i.e. AS FAR A I KNOW(!) the
> system is _not_ connected to a TV aerial.

I would start to make sure that the system is not connected to anything
else. Then try the TV's without the distribution amplifier.

After that, try the TV's with a short cable connected to the modulator
directly. Try the lightest one first :-)

gr, hwh

[sintv]

On Wednesday, February 13, 2013 4:33:02 PM UTC, hwh wrote:

> On 2/13/13 4:26 PM, davidrobinson.co.uk wrote:
>
> > A relative has a Vision V40-104 RF modulator feeding two TVs through a
>
> > small distribution amplifier. There is nothing else on the RF cable
>
> > except the return path for two magic eyes, i.e. AS FAR A I KNOW(!) the
>
> > system is _not_ connected to a TV aerial.

Why not just run another cable from the dish and connect up to a Freesat/Freesky box. Would eliminate the modulator and make life easier for you!

[Bill Wright]

davidr...@postmaster.co.uk wrote:
> A relative has a Vision V40-104 RF modulator feeding two TVs through a
> small distribution amplifier. There is nothing else on the RF cable
> except the return path for two magic eyes, i.e. AS FAR A I KNOW(!) the
> system is _not_ connected to a TV aerial. They use Freesat
> exclusively: a PVR in the lounge feeds the lounge TV via HDMI, and the
> other two TVs via RF.
>
> Everything worked fine for at least a year.
>
> A few months back, intermittent sound problems appeared on one of the
> TVs fed from the modulator. Sound would be fine sometimes, but covered
> in hiss/buzz other times.

One thing to be aware of is that these modulators are very versatile.
They do various standards, I, BK, etc. It is possible to vary the audio
level, video gain, etc. Occasionally they seem to have a memory problem
and switch standards, etc. This usually shows up as poor sound. Download
the instruction sheet. If you can't find it I'll scan it for you, but it
would mean standing up...
Be aware that some of the mods (last year, early, I think it was) had a
fault by which the display when you are setting the audio standard is
wrong. Can't remember the details but it was confusing. Also, you can
lock the settings. Press and hold both buttons.
You can alter the RF output level and at max it is very high, 24dBmV,
enough to overload some amps.

Bill

[J. P. Gilliver (John)]

In message
<3ec3be3f-98fb-4c5f...@fw24g2000vbb.googlegroups.com>,
"davidr...@postmaster.co.uk" <davidr...@postmaster.co.uk>
writes:
[]

>A few months back, intermittent sound problems appeared on one of the
>TVs fed from the modulator. Sound would be fine sometimes, but covered
>in hiss/buzz other times. They've tried re-tuning, but it doesn't seem
>to help. (I gave instructions over the phone - I assume they were
>doing it correctly, but can't be sure).

Sounds to me like video on sound - in theory should be less of a problem
with FM sound than it used to be in 405-line days, but in practice with
intercarrier sound strips in the telly, it can still happen. (Especially
if there's overmodulation on the video carrier.)
[]

>They are both old analogue-only TVs. The first is probably 25 years
>old (Sony, still apparently working well), the second is probably 7
>years old (Goodmans, built in DVD, bought from Tesco).

I'd guess at least the latter one is synthesized tuning, which probably
only goes in whole UHF channels. If the modulator has drifted slightly
so that it's no longer on a nominal channel, that might cause the
problem. Or the tuner's reference drifting similarly.

>
>Thanks for any help or advice.
>David.
>
>P.S. Didn't go down Freeview route as relative probably can't cope
>with re-tunes. Hoped this would be a "set and forget" Freesat system,
>and for over a year, that was true.

I _think_ you can get FreeView boxes that auto-retune. And of course the
satellite system won't remain set in stone forever, either )-:.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Radio 4 is one of the reasons being British is good. It's not a subset of
Britain - it's almost as if Britain is a subset of Radio 4. - Stephen Fry, in
Radio Times, 7-13 June, 2003.