Stereo RF Modulators - Are they worth it?

maggy_thatcher

Hi,

We've a Sky box in one room, and a regular co-ax linking it to two other TVs via the RF2 socket on the back. The picture is okay (could be a bit better - may look into moving the channel at some point soon, or taking the attic aerial out of the loop), but I've noticed that it's only a mono sound source that doesn't have quite the "power" that the original source had. I was wondering has anybody any experience with external RF modulators -- in particular ones that perform stereo encoding, and are they generally any better than the built in modulator that's built into the box? I was looking at options such as this one

Putting in a SCART/HDMI run between the TVs isn't really an option (the house was pre-wired with coax, so that what I'm sticking with). Using a "video sender" didn't work well at all, as I think the walls in our house are too well built -- I could get a fuzzy picture that would break up as soon as I walked in front of it, as well as the fact that the two alternate TVs are in perpendicular directions when it comes to the "main" box.

Advice would be much appreciated!

watty

It might possibly to is Stereo via Zweikanalton in Germany, but I doubt it. (PAL B/G setting 5.5, 5.742MHz = Zweikanalton)
Worryingly they claim the PAL-I is 5.5, PAL-I is 6MHz.

It's very likely just stereo to Mono mix and Mono sound. On PAL-I it's only mono.
PAL-I (UK, Ireland and other countries) only has mono FM (6.0 MHz offset), and stereo is done by Digital Nicam system. You can get Nicam encoders, but that modulator won't have one and no consumer builtin or external RF modulator has.

It's just a plain ordinary RF Modulator, with Zweikanalton.

Most video senders are very very poorly made. Down to a price..
See http://www.techtir.ie/tv-radio/video-senders

http://en.wikipedia.org/wiki/Zweikanalton
http://en.wikipedia.org/wiki/PAL
http://en.wikipedia.org/wiki/Nicam

Note that NO DVD recorder or Nicam VHS actually record and replays Nicam. They ALL decode the Nicam with same chip as in a TV tuner, and then on VHS it uses the FM HiFi stereo audio heads and on DVD recorder encodes to MP2 along with the MPEG2 in the MPEG-PS written to disk. On both families the stereo playback is only via SCART or Audio RCA L&R, or on DVD player, possibly SPDIF digital (optical or RCA) also if installed. There is no re-generation of Nicam. The built in RF modulator is just mono (sum of L+R).

maggy_thatcher

watty wrote: »

It might possibly to Stereo via Zweikanalton in Germany, but I doubt it. (PAL B/G setting)

It's very likely just stereo to Mono mix and Mono sound. Espeically on PAL-I
PAL-I (UK, Ireland and other countries) only has mono FM (6.0 MHz offset), and stereo is done by Digital Nicam system. You can get Nicam encoders, but that modulator won't have one and no consumer builtin or external RF modulator has.

It's just a plain ordinary RF Modulator.

I checked the technical specifications -- it looks like it does use dual-channel audio in PAL B/G mode:

Audio carrier frequency
PAL I : 5.5MHz
PAL B/G: 5.5, 5.742MHz

I know it would be mono-only in PAL/I mode -- so if I were to use something like that I'd switch the TV over to German mode or something like that (actually I think my TV allows to set PAL mode on a per channel basis, must check that when I get home).

If there are better (but still affordable at domestic level) modulators, I'd love to know!

watty

Edit it's Zweikanalton
Very very few UK/Ireland TVs do Zweikanalton, usually just one channel.


Forget modulators. The decent ones are more expensive than a Freesat HD PVR box. And still won't give you stereo.

maggy_thatcher

Oh well

Thanks anyway...guess I'll have to make do with crappy sound

Antenna

watty wrote: »

Edit it's Zweikanalton
Very very few UK/Ireland TVs do Zweikanalton, usually just one channel.


Forget modulators. The decent ones are more expensive than a Freesat HD PVR box. And still won't give you stereo.

A lot of TVs sold here , including ones in Lidl, can apparently handle German analogue TV stereo sound (with PAL B/G), according to their specs. I assume most/all can set PAL mode per TV channel, so you can have PAL-I for Irish analogue terrestrials and PAL B/G for modulator channel.

BTW The frequency coverage of that modulator
"Frequency range: UHF-470-872MHz; VHF 126-300MHz"
is handy covering those VHF frequencies too if there is a lack of suitable channels at UHF - could be an increasing problem in a few years with the higher UHF channels - the so-called digital dividend spectrum - being sold off to other users, whilst especially 230-300MHz is clear of any strong over-the-air signals that might affect an in-house modulator, provided you have no cable TV (which does use those frequencies) also.