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| hcs |
 Posted: Mon Nov 26, 2007 3:59 pm Post subject: |
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| sorry, the pics arnt comming up on my computer |
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| torbjorn |
| Posted: Mon Nov 26, 2007 3:53 pm Post subject: |
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Those cable filters were used in some early cable tv networks for descrambling pay tv channels.
The scrambling scheme was very simple, as a strong interfering carrier was transmitted at a frequency very near the respective pay channel. An ordinary tv would get its RF stage blocked by that carrier, and the filter attenuates the carrier so it doesn't cause any harm.
Those filters were rented to the customers wanting to see the pay channels.
The drawbacks of that system were that it was not possible to scramble more than a few channels at the same time by that method, as a lot of strong carriers would cause intermodulation problems in the amplifiers of the cable network. And that it was fairly easy for anyone wanting to watch those channels without paying to build an DIY filter (in its simplest fashion, a suitable T stub of good quality coax cable).
At least in Sweden, no cable networks are using that scrambling method today but it was common in the early nineties. |
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| Guest |
| Posted: Mon Nov 26, 2007 12:13 pm Post subject: |
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| s37d wrote: |
| So, what is the purpose of it and how/where does it hook up? ty |
yes its a cable filter. or lightning suppressor. but I am not sure if it will really works for its intension.
yawars. |
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| s37d |
| Posted: Mon Nov 12, 2007 8:49 am Post subject: |
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| So, what is the purpose of it and how/where does it hook up? ty |
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| vtech |
| Posted: Sun Nov 11, 2007 3:38 pm Post subject: |
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| It is a cable filter |
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| Guest |
| Posted: Sun Nov 11, 2007 2:13 pm Post subject: |
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| Ah, what exactly is it used for? |
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| gridnutter |
| Posted: Sun Nov 11, 2007 2:07 pm Post subject: |
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| Looks like an attenuator.... |
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| s37d |
| Posted: Sun Nov 11, 2007 10:27 am Post subject: Can anyone identify this item? |
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Can anyone identify this item? Not sure what it is.
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