Almost all types of modern lighting can produce VHF interference, an
unfortunate consequence of 'green' legislation in many countries.
My method is to go and test an example with a FT817 and short antenna and
check for noise.
CFL bulbs, I have seen low frequency HF noise but nothing at VHF. Most of
the lighting at my EME station is 230V CFL bulbs.
LED lighting - most have some form of SMPS and the majority, even with an
EMC marking, do produce some VHF noise. Some examples were detectable at
12ft with a 'rubber duck' antenna on 144MHz. The LED 'halogen replacement
bulbs' sold in the local DIY stores are a complete nightmare. The SMPS is in
the bulb holder with almost no room for EMC filtering!
Conventional fluorescent tubes themselves are fine at VHF (not so hot on
1.8MHz) but I have detected VHF noise from newer 'electronic ballast'
systems. Conventional ballasts I have not seen any VHF issues.
Halogen bulbs are fine, the ones I have in the kitchen are 230V ones. BUT;
the low voltage ones tend to have a SMPS or 'electronic transformer' which
can be as bad as LED systems.
One problem in Europe is that even the ones with a CE certification, which
should include EMC testing, does not address the issue of radiated emissions
from the supply cables above 30MHz.
If I had a choice I would stick to filament bulbs or tube fluorescents and
not worry about the cost.
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