zapped from the knobs

Discussion in '"Boat Anchor" & Classic Equipment' started by VA7WPN, Jan 19, 2013.

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  1. VA7WPN

    VA7WPN Guest

    What Im going to do is... Build my station, build the grounding for all of the equipment into a singular bus bar. The bus bar will go out to a 6' grounding rod pounded into the ground. Ill Build my test bench the same way, along with installing a few antenna's outside of the house. Properly ground the Tower, and the remote antenna switch as well. All with individual lightning protection. Maybe, Ill get this done by the end of the spring. Until then, Ill work with what I have. :) Taking ALL the advice I can, into consideration.
     
  2. KE3WD

    KE3WD Ham Member QRZ Page

    A grounding scheme is possibly good for lightning protection, likely won't stop RF in the shack.

    A balanced antenna, such as a dipole, properly installed with balun at feedpoint, can eliminate RF in the shack as well as the fact that the dipole, being balanced, does not need an Earth Ground in order to operate properly.

    Be sure to BOND that ground rod to the main electrical ground rod when you do it.


    73
     
  3. VA7WPN

    VA7WPN Guest

    Tomorrow night, Ill be running the Long wire out side... some how.
     
  4. W4HAY

    W4HAY Ham Member QRZ Page

    I've had fair results using off-center loaded (shortened) dipoles in apartments, condos and motel rooms both at QRP levels and around 20-30 Watts. The loading coils were made with 22 AWG magnet wire on forms of 1" PVC pipe. The were routed between rooms and along hallways. use your imagination. Typically they get out better than they receive because of noise from consumer electronic and electrical devices.

    In college I had a crystal controlled rig that put out about 20 watts and used it with a random wire tossed out the window and worked against the dormitory steam heat radiators. If they're made of metal, the air conditioning ducts can sometimes be made to work as a counterpoise.
     
    Last edited: Jan 21, 2013
  5. KE3WD

    KE3WD Ham Member QRZ Page

    Longwire is typically one of the hardest antennas to keep RF out of the shack with. The reason is that there is no real counterpoise for the wire other than the shield on the coax and the chassis' of the radio gear itself.

    Besides that, a random longwire really has to be rather loooooong to be efficient at HF frequencies.

    There are ways to work that you can utilize, though.

    Consider a true dipole and feed it with ladderline to a tuner that has the proper balun on or in it to use balanced ladderline and not just coax. This has advantages over coax feed in that line losses will be a lot less and when using any compromise antenna, the line losses can really eat up the efficiency of the thing. Sure your wattmeter might be showing that there's for instance, 100W or possibly more happening at the transmitter, but that says nothing about how much of it is just heating air due to the poor efficiency of the radiator.

    Putting the same antenna outdoors will likely not solve your problem. Might reduce things a bit, but doubtful, as this is not a situation of your antenna being too close to your operating position, even though it is, it is a situation where a radiator of extreme short length for the frequency also has no counterpoise (other than the coax shield and the radio itself, which is why you are getting bitten).

    Some have suggested the MFJ counterpoise box known as the Artificial Ground. While that may work here, it will have little impact on the efficiency of what you are trying to use for an antenna. In my way of thinking, that money could be better spent on an antenna that could be erected in the winter, such as a ground mounted Vertical with some radials on the ground underneath it. Especially if you can get your hands on a used one and save some money. Even after the spring thaw and you erect some good wire such as dipole or that G5RV, you will find that having a Vertical out there as well, along with a good antenna switchbox, will give you some options. The low takeoff angle of the properly installed vertical antenna with radials can often make the difference on the DX, while that G5 might prove to be better on the "local" nets on this continent.

    Another good indoor antenna is the small magnetic loop. These must be tuned each time you turn the Big Knob, but that narrow bandwidth can also translate to an antenna that is right there in the room with you that makes contacts. If you don't want to build one, MFJ sells these also.


    73
     
  6. VA7WPN

    VA7WPN Guest

    Im going to be running some Coax threw a window for now, as my house is bricked, Im not going to punch any unnecessary holes at this point.
     
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