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On our farm, we use FRS radios for communication. Everyone carries a radio, which are inexpensive Cobra or Uniden models.We have a Cobra MicroTalk Model # PR4250WX that we use as a base radio at the farmhouse. Cobra claims that this is a 5 watt radio. I was able to get a schematic, and have wired in a hand mike, and an amplified external speaker. The batteries have been replaced by an external supply. I want to improve the range and reception, so I built a simple vertical ground plane antenna using plans in the ARRL handbook as a guide.

NOW... How do I connect the antenna to the radio???? Can I just solder a short piece of RG58 to the point where the rubber duckie was connected, and then put an SO-239 on the other end to hook to the antenna coax? This seems logical to me, but I've not had much experience with vhf, and I don't want to blow the radio. If anyone has input on this I would REALLY appreciate it. Thanks in advance.

- 399

Sounds like you have it figured.

Not that I suggest worrying about it, but what are the laws for FRS there.

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XDX74

741N -

The deal here is "run what ya brung." As long as I don't interfere with any official government communications, I can pretty much do what I want. However, if I add any new equipment, I have to have the local policia commandante check it out...which is no problem because I suck up by tuning up and repairing all of their radio equipment. Hey... it works for me.

- 399

you need to locate the rf ground return trace on the transceiver's printed circuit board. (the dc & rf ground returns may be one and the same) once you locate it just extend the connection from the pc board to the ground side of the connector (so-239 or "bnc") and the antenna output to the center pin. if the dc & rf board grounds are separate you'll see rf bypass capacitors connected between them. if you find this is the case let me know, i can tell you what needs to be done. you usually won't find this to be the case since dc & rf ground isolation was reserved for equipment to provide the option of operation from both positive and negative ground vehicles.

When in Rome.....

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XDX74

A farm in Columbia?

Good relations with the Policia?

Any job openings?

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XDX74

BTW, FRS is UHF.

Well, like I said, I don't have much experience with this.

- 399

At FRS frequencies, RG-58 would be pretty close to my LAST choice. Really high loss stuff.

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If you're like everybody else,
you're about average.
73 de K7KBN

For a base, why all the butchery of a cheap handheld? Get ya an Alinco 435 series UHF ham mobile. Simple mod to go out of band and there ya got a 35 watt FRS/GMRS base.

And low loss, 100% shielded RG8 coax is a must for VHF & up.

good luck

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