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Re: NEON- Neon and radio interference
Dear Dimitrij,
No problem if these are all transmitting antennas and no recievers -
but how you should know?
There was a big installation on a rooftop interfering with the personal
pager system in the 130 - 144 MHz range when they called me.
Looking into miller's mook (and my ham radio anti-interference books)
I suggested to use chokes (single layer 0.2 Cu enameled on 6mm Ferrite rod)
in parallel with a ohmic resistor of abt 500 Ohms, 2 Watts.
I told the installers to connect these "resistor shunted chokes" directly
to the electrodes within the channel letters. First the leads from the
transformer, if this will not work, add more in each channel letter up to
every electrode - GTO connection is choked.
Two of them at the transformer wires had been sufficient to calm the
customer and the postal frequency survey comittee. All OK now.
The effect is caused by plasmon oscillations of the mercury, tuned by the
inductance and stray capacitance of the GTO wires.
In these cases you should stay to core and coil transformers,
solid state in this case is a NEVER, or you can end up in court or jail.
Marcus
> Hello, the List.
>
> I am negotiating now a channel letters job on a roof of a building.
> The roof is full of radio aerials, satellite dishes, etc. and customer is
> worrying that neon transformers may cause radio interference.
>
> Does anyone have experience whether things like neon tubes and/or transformers
> and/or flashers are incompatible there? Or what kind of transformers should better be used
> in such installations? May be some electrical tricks?
>
> Thanks for your inputs
> Dmitrij
>
>
References: