[RFI] Fishtank Lighting RFI on 3.8 and 1.8Mhz

K1ZM at aol.com K1ZM at aol.com
Sun Nov 23 17:32:26 EST 2003

Hello out there.

I am trying to remedy some TV birdie-like (or touchlight-like type RFI)  that 
is coming from special ultraviolet lighting used to stimulate plant growth in 
a large aquarium.  Apparently a combination of ultraviolet and white light 
makes algae grow on the rocks and helps the plants survive - and these lights 
must be on for about 6 hours daily.

The offending signals sound somewhat like TV birdies and are quite unstable - 
with the most offensive RFI occuring around +/- 3.8Mhz and on +/- 1.830Mhz.  
These signals drift back and forth - sometimes slowly but more often quite 
erratically.  One moment they will be on 3803 and then they will be present as 
low as 3795.

The specific system I am dealing with has ACTINIC WHITE - VHO-1 and SUPER 
ACTINIC R - VHO - 1 (ultraviolet light) bulbs in it - 2 each/ 4 total and has 
twin power supplies of sorts supplying the voltage to the lamps.

The bulbs (which look like very long fluorescent tubes) are made by 
Ultraviolet Resources International - and are quite expensive - around $100 apiece.

Powering off the units kills the birdies COLD - and they definitely reappear 
as soon as the unit is turned on again.

As this one is totally new to me, I am unsure how to proceed.  Has anyone 
ever seen this one before?  What type of fix will work and where should it be 

(Yes, I know three sticks of DYNOMITE in the right place will solve my 
problem - but this guy is a friend and I am trying to find a solution that works for 
both of us.)

Any ideas out there?

Sure would appreciate some help with this one.

Many thanks.


K1ZM at aol.com

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