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john4378
04-16-2022, 09:43 PM
Hi guys,
I recently decided to get back into CB radios after probably over 30 years (since I was a kid). I donít remember them being this complicated! Iím a total newbie now. After some research, I bought a Uniden bearcat 880 CB radio, a Pyramid 12V 5 AMP power supply, and a K40 CB antenna for my home base station. After setting these up, my SWR reading is extremely highly (3.5+). I have my entire setup within one room on the second floor of my house. My antenna is sitting in a metal baking pan (1ft-1ft) on my windowsill and my CB radio and power supply are on the other side of the room. Iím not sure what the issue is due to not knowing much about CB radios. Another issue is that my microphone doesnít seem to be properly functioning. Iíve tried using the talkback feature on my radio and Iím getting no response from my mic. Iím not sure if microphones can affect SWR or not. If anybody has any tips for getting my SWR lower or how to better ground my setup please let me know. Maybe I need a bigger pan or use tin foil for my antenna?


Thanks,
John

Alabama Buckeye
04-17-2022, 10:51 PM
Grounding! How is that baking pan doing for ground. Slam a 2-3' length of rebar in the ground, diagonally is better, attach 14AWG copper magnet wire to rebar, extend wire to pan and bolt it on.
Ground rod diagonally more likely to pass through moist spot.
Though your ground plane is still absent. A vehicle magnet mount antenna uses the vehicle as ground and ground plane. A whip antenna is only 1/2 of an antenna system. 1/4 wavelength antennas need a ground plane. Don't key up but to check SWR only, until resolved. You need a grounded house roof mounted antenna at the least.

Until you get an antenna up in the air you're not going very far if at all. Look into 1/2 wavelength antennas. Possibly on a TV antenna mast. I put twin 102" whips (1/4 wavelength) atop an all steel building and got nothing of consequence for reception.

Alabama Buckeye
04-17-2022, 11:06 PM
As to talkback. Using external speaker may pay dividends. This feature is to hear yourself talk. Of course you had the radio volume up. Mic gain? You might consider a dummy load rated to the output of radio.

https://www.walcottradio.com/help/mic-gain-control-where-to-set-it-cb-radio.php
"Having worked in the communications business for almost 2 decades, I can tell you the Mic Gain control along with the RF gain control are the most common to be positioned incorrectly."
https://www.walcottradio.com/help/what-is-talkback-tback-cb-radio.php
(https://www.walcottradio.com/help/what-is-talkback-tback-cb-radio.php)Talkback allows you to hear yourself, which tells you that your radio is probably transmitting.

JesseJamesDallas
04-18-2022, 06:31 PM
...my SWR reading is extremely highly (3.5+). I have my entire setup within one room on the second floor of my house. My antenna is sitting in a metal baking pan (1ft-1ft) on my windowsill and...

Well I ain't never...:300 (96):

A baking pan? For real?.............couldn't find a Pizza pan?

Things haven't got more complicated in the last 30 years...Things that were true then, are still true today...Baking Pans make lousy ground planes...:pop3:

GobblerK5
04-19-2022, 11:41 AM
String a dipole antenna up a tree instead of that K40...

Sent from my motorola one 5G UW ace using Tapatalk

Alabama Buckeye
04-29-2022, 01:21 AM
Yeah, Dipole! I'm working on my 2nd Inverted Vee dipole. Making a fancy wire attachment head with dual parallel choke UnUnions; should handle 600W. Making use of them cheap no brand iron toroids. Finally got some feedback from seller on permeability on them; 125. Wired 'em up with 16AWG mag. wire real nice and tight. Waiting for 3D printer made housing for the attachment head and Unions.

98.5" legs and 5'8" height of center above tips of antenna legs is a 90 degree Inverted-Vee. I'll use 12AWG mag. wire for the antenna legs. Make it a 60 degree for nearly omni-directional; but no tighter.