• rffdback

    From LU9DCE@21:5/101 to BBSRT on Tue Jul 2 16:40:07 2019
    PIRATE RADIO SURVIVAL GUIDE
    Note: this chapter is from the book "Pirate Radio Survival Guide" written by Radio Doomsday, and Captain Eddy of The Radio Airplane. If you like this book a like to support their efforts, you may send a donation of your choice to either Capt. Eddy at PO Box 452, Wellsville NY 14895.

    Please note that some chapters refer to illistrations or drawings, these could this BBS version of the book. If you would like the illistrations or have other may inquire at the above adddress.

    RF FEEDBACK


    No matter what you do, RF Feedback WILL rear its ugly head in one form or ano station. Perhaps the only way to avoid RF Feedback is to use a Studio To Transm to get your transmitter away from the rest of the station. Don't worry, you won that extreme! RF Feedback can be cured 99.99% of the time. All it takes is a li of the problem and some tried and true cures.

    RF Feedback is caused by being in close proximity to a source of High Level R doesn't mean that your equipment is really at fault, other than being too darn electronic is a potential victim for RF Feedback and it will be quite apparent present!

    The simplest cure for RF Feedback is the RF Choke. A RF Choke is a coil wrapp ferrite core to impede the flow of RF Energy. Radio Shack manufactures a snap o well. A cheaper, and sometimes just as effective, alternative is the ferrite ro Radio's loopstick antenna. Whatever you can come up with should be used. The ke Chokes is in the amount of turns you can use: The more the better. Places to use chokes are on the AC Power cords and ALL Audio Cables. Electrical tape help wraps in place.

    Another simple way to reduce the possibility of RF feedback is to make sure t cords or audio cables are high quality shielded cables. Cheap cables are more t worth. Also try plugging your transmitter and audio source into different AC ou

    If you still suffer from RF Feedback problems, the next step is to install By the effected equipment. I suggest using .01 uF Ceramic Disc capacitors rated at properly de-RF a piece of gear, you need to concentrate your efforts in two pla Power Supply of the unit. Typically, RF will enter via the AC line cord and get supply affecting everything else. Open the unit, MAKE SURE IT'S UNPLUGGED! Loca power supply, if you don't know what a power supply looks like you might want t who does. Places to install bypass capacitors are on each side of the AC line c across the Secondary windings of the transformer to ground and finally, across ground. This should clear up any RF getting into the power supply.

    Should you still suffer, the next step is to bypass all the line in and out c Simply connect your capacitor from the Hot Side (Center Conductor) to the chass make sure the equipment is properly grounded in the first place! Do this for a regardless if they are used or not. And finally, don't forget about your speake might be bypassed as well since speaker wire tends to act as an antenna!



    If you try all this and you still have problems, try moving the transmitter o sometimes a few feet can make all the difference in the world. You may even hav trying another tape deck, some cheap tape decks are impossible to protect from











































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