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Hello David,
What radio reception are you concerned with? Interference from the switch-mode power supply in the lamp fixture could be radiated, or it could be getting to the radio through the 12 volt circuit. RadioShack ferrites could help, but I think we need more info. Chuck david wrote: Hi all Is there an easy soloution to stop the interfrence that florescent lamps the 12volt ones from tandy/dick smith cause to radio reception. thanks David |
Ok, then the interference is being radiated. Take the radio
out on deck and see if the interference drops to an acceptable level when you are 10-15 feet from the lamp. If so, then the answer may be to use an external antenna. Nothing elaborate is necessary. Maybe a twisted pair from the radio antenna jack to the antenna would help cancel any radiation from the lamp to the feedline. Can't think of anything else to try that wouldn't be "over the top". Someone else may have a better suggestion. Good luck, David. Chuck david wrote: Hello Chuck Thank you for your reply. Its just an AM/shortwave reciver it makes no diffrence if it works from the ship supply or the radios internal batteries. the florescent lamps internals are a transformer a switch a transistor on a heat sink 3or 4 capactors and a diode which i disabled to avoid the .6volt drop that seemed to reduce the interfrence a bit (i think). the above is from memory I'd have to open one up again to be more accurate. |
I'd say that turning off the flourescent lights when using the radio is the
simplest solution. Install an indandesent for use during those times if you need light at the rig. Doug "chuck" wrote in message ... Ok, then the interference is being radiated. Take the radio out on deck and see if the interference drops to an acceptable level when you are 10-15 feet from the lamp. If so, then the answer may be to use an external antenna. Nothing elaborate is necessary. Maybe a twisted pair from the radio antenna jack to the antenna would help cancel any radiation from the lamp to the feedline. Can't think of anything else to try that wouldn't be "over the top". Someone else may have a better suggestion. Good luck, David. Chuck david wrote: Hello Chuck Thank you for your reply. Its just an AM/shortwave reciver it makes no diffrence if it works from the ship supply or the radios internal batteries. the florescent lamps internals are a transformer a switch a transistor on a heat sink 3or 4 capactors and a diode which i disabled to avoid the .6volt drop that seemed to reduce the interfrence a bit (i think). the above is from memory I'd have to open one up again to be more accurate. |
fluorescent lamps interferance
Hi all
Is there an easy soloution to stop the interfrence that florescent lamps the 12volt ones from tandy/dick smith cause to radio reception. thanks David |
Hello Chuck
Thank you for your reply. Its just an AM/shortwave reciver it makes no diffrence if it works from the ship supply or the radios internal batteries. the florescent lamps internals are a transformer a switch a transistor on a heat sink 3or 4 capactors and a diode which i disabled to avoid the .6volt drop that seemed to reduce the interfrence a bit (i think). the above is from memory I'd have to open one up again to be more accurate. |
In article ,
"david" wrote: Hi all Is there an easy soloution to stop the interfrence that florescent lamps the 12volt ones from tandy/dick smith cause to radio reception. thanks David that's an easy question....the answer.....TURN THEM OFF....... Me |
"Me" wrote in message
... In article , "david" wrote: Hi all Is there an easy soloution to stop the interfrence that florescent lamps the 12volt ones from tandy/dick smith cause to radio reception. thanks David that's an easy question....the answer.....TURN THEM OFF....... Me OK guys...its sea story time! After several years of fighting florescent desk lamps in US Navy HF receiver sites (110 VAC versions) using the turn them off, get them out the building policy, I was shocked to see a new construction building in Alaska having florescent fixtures being installed in the ceiling. Not only that, but the Naval Research Lab was supplying the fixtures as GFE (government furnished equipment). This was in 1970 and I was very surprised to find out there exists special ballasts and fixtures for florescent lights in radio reception areas. The diffuser cover over the tubes had a very fine wire mesh laminated into the translucent material and grounded to the fixture case. We powered up a fixture in the building and I used a Stoddard NM25 RFI meter and swept the HF spectrum. The fixture was quiet with the diffuser in place, and fairly quiet with the diffuser open. Bottom line--there are at least 110VAC RFI reduction fixtures available. I have no idea what the taxpayers paid for them. 73 Doug K7ABX |
In article .net,
"Doug" wrote: "Me" wrote in message ... In article , "david" wrote: Hi all Is there an easy soloution to stop the interfrence that florescent lamps the 12volt ones from tandy/dick smith cause to radio reception. thanks David that's an easy question....the answer.....TURN THEM OFF....... Me OK guys...its sea story time! After several years of fighting florescent desk lamps in US Navy HF receiver sites (110 VAC versions) using the turn them off, get them out the building policy, I was shocked to see a new construction building in Alaska having florescent fixtures being installed in the ceiling. Not only that, but the Naval Research Lab was supplying the fixtures as GFE (government furnished equipment). This was in 1970 and I was very surprised to find out there exists special ballasts and fixtures for florescent lights in radio reception areas. The diffuser cover over the tubes had a very fine wire mesh laminated into the translucent material and grounded to the fixture case. We powered up a fixture in the building and I used a Stoddard NM25 RFI meter and swept the HF spectrum. The fixture was quiet with the diffuser in place, and fairly quiet with the diffuser open. Bottom line--there are at least 110VAC RFI reduction fixtures available. I have no idea what the taxpayers paid for them. 73 Doug K7ABX There are RFI eliminators that can be added to florescent lighting fixtures, as an after-market upgrade. GE made all the ones that I had installed in every Cannery Office in alaska. This was before the advent of computer networks in the offices, and when that happened we moved the radio's and antennas out away from the offcies and clear out in the brush, and just left the Control Heads, back in the plants. SEA 322's, 330's, and 325's work really well, at the end of 3000 ft of telephone wire. Bruce in alaska there is always a way to fix a problem, if money isn't a part of that problem...... -- add a 2 before @ |
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