What's RF Modulator Chn38 for in Recivers?

bostephen

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Hi Guys & Girls,

I have seen "RF Modulator Chn38" in Receivers but failed to use it. Whats the use of this item? Here is the picture showing.
h**p://www.satellites.co.uk/satellite/attachment.php?attachmentid=22682&stc=1&d=1246480931
 

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Mickha

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t's just the default setting for the RF out, in case you want to connect it to your TV using the coax cable, you can usually change it, to avoid interference, but as most people use a Scart connection, or other, it is somewhat redundant.
 

Analoguesat

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For distributing signals the old fashioned way using aerial cables instead of scart.

The advantage of rf distribution is its much much easier to distribute around the house - Ive got all my equipment cross wired in weird and wonderful ways so any of the receivers can be sent to any one of about three different places :D
 

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bostephen said:
Hi Guys & Girls,

I have seen "RF Modulator Chn38" in Receivers but failed to use it. Whats the use of this item? Here is the picture showing.
h**p://www.satellites.co.uk/satellite/attachment.php?attachmentid=22682&stc=1&d=1246480931

Of course, must be noted a lower grade signal distribution to the TV. Exactly what is says on the tin, the A/V signal is modulated onto a RF carrier. The TV then has to de-modulate this signal. Ch38 represents an 8MHz wide channel with a vision carrier of 607.25Mhz

If using a scart or component connection, then no need to connect via RF mod.
 

bostephen

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PAS7_10 @ 68.5°E, 1.8 m Astra C Band Dish (for roaming) but now on Thaicom 2/5 @ 78.5, 90 cm (GTV) offset on Sirius 4; ALL FTA and Astravox VSR-400 Reciever, I Still have 2 analogue recievers...(4 what? noo one knows!!)
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Could this be the way a receiver can send more than one channel so that selection can be done at the TV? If I may ask, how is this done?
 

satelliteman

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Only the one output satellite channel at source can be distributed to other points via the modulator. You can of course daisy chain several receivers IN and OUT of the modulator so a 'TV' can tune into each of the receivers. The receivers would have to be set on different channel numbers in order for this to work.

If that's what you are referring to.
 

bostephen

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PAS7_10 @ 68.5°E, 1.8 m Astra C Band Dish (for roaming) but now on Thaicom 2/5 @ 78.5, 90 cm (GTV) offset on Sirius 4; ALL FTA and Astravox VSR-400 Reciever, I Still have 2 analogue recievers...(4 what? noo one knows!!)
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satelliteman said:
Only the one output satellite channel at source can be distributed to other points via the modulator. You can of course daisy chain several receivers IN and OUT of the modulator so a 'TV' can tune into each of the receivers. The receivers would have to be set on different channel numbers in order for this to work.

If that's what you are referring to.

Pliz post pictorial illustration if u can, of how this is wired.
 

satelliteman

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Sorry it's too late to start drawing pictures ;)

Example for connection of two receivers to one TV via co-axial.

Connect RF OUT from receiver one to the input of RF modulator on receiver two. Then output of receiver two to TV. Tune both receivers in.
 

bostephen

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satelliteman said:
Ch38 represents an 8MHz wide channel with a vision carrier of 607.25Mhz.


Would setting above or below 38 achieve a wider frequency (for whatever a purpose-maybe improving pic quality)?
 

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No they are all the same bandwidth - just the centre carrier frequency is different..
 

bostephen

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1.8 m C Band Dish on
PAS7_10 @ 68.5°E, 1.8 m Astra C Band Dish (for roaming) but now on Thaicom 2/5 @ 78.5, 90 cm (GTV) offset on Sirius 4; ALL FTA and Astravox VSR-400 Reciever, I Still have 2 analogue recievers...(4 what? noo one knows!!)
My Location
Africa, Uganda (Log. 32.8°E, Lat. 0.7° N)
satelliteman said:
Sorry it's too late to start drawing pictures ;)

Example for connection of two receivers to one TV via co-axial.

Connect RF OUT from receiver one to the input of RF modulator on receiver two. Then output of receiver two to TV. Tune both receivers in.



Very clear instructions!! Thx

Any idea about the maximum capacity of "stacking" the receiver signals that the modulator/s can manage?
 

satelliteman

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Due to domestic RF modulators being 'double side band' only, care has to be taken as not to cause cross modulation problems. Also see regarding taboo channels > _http://www.kat5.tv/taboo.html
 

bostephen

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1.8 m C Band Dish on
PAS7_10 @ 68.5°E, 1.8 m Astra C Band Dish (for roaming) but now on Thaicom 2/5 @ 78.5, 90 cm (GTV) offset on Sirius 4; ALL FTA and Astravox VSR-400 Reciever, I Still have 2 analogue recievers...(4 what? noo one knows!!)
My Location
Africa, Uganda (Log. 32.8°E, Lat. 0.7° N)
Thank you guyz for your helpfulness, God bless you.
 

HB13DISH

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One very important drawback for using RF modulator is that the audio by default would be mono, instead of stereo, while the AV output would be stereo.
Perhaps if your equipments has support for stereo (TV, VCR, etc.) using NICAM or other systems, then there might be a way to listen to stereo.
 
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