THE BEARDED ONE SPEAKETH...

Howdy,the filter in question is a seven branch Chebyshev high pass variant.The cutoff frequency is approximately 430 Mhz and the attenuation of the unwanted signal is about 42db.The P.C.B. MUST be constructed on double sided S.R.B.P. (synthetic resin bonded paper) copper clad board.The method of construction is up to yourself,but those without the equipment to etch a proper board can still make this P.C.B.The unwanted copper is removed by first carefully scoring the copper thru to the substrate with a sharp stanley (or craft) knife,it is essential to be very accurate to the measurements provided to attain the expected results.Next carefully lift an edge of each unwanted strip,then peel them off with the aid of a hot soldering iron and a pliers.

Keep a supply of new blades to hand as cutting the copper will blunt 'em real quick,and have spare copper clad board too as you will need to start again if you screw it up!The filter must be housed in a screened enclosure,and as it has an odd number of branches,(seven),it can be connected to the T.V. either way around.The capacitors in the filter are formed by the interaction of the top and bottom copper surfaces using the board substrate as a dielectric.The coils should be wound on the shaft of a 3mm drill bit and accurate placement of them and the earthing links should be observed.

A final note of advice from beardy here,make a few of these,you may need them.Not all T.V.I. is caused by bad transmitters,sometimes the television itself can have problems inherent in its design or construction that will make it susceptible to interference,and generally the older the telly the worse the problem.Hope this will keep all your neighbours sweet for yez...

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