I have mounted my new Shark Hamstick on my tacoma. I have verified with a multimeter that i have a solid continuous ground plane from the bed to the frame to the cab all the way to the front bumper. I can not get the SWR below 2:1. I am wanting to run my qrp radios and 2:1 is not acceptable. Thoughts?
Hi John, sorry you are having troubles. Can you fill us in with a little more information? Shark makes a mini and a standard size ham stick. Which are you working with? What band are you on? The lower the band the narrower the bandwidth will be. Do you have an analyzer available to determine what portion of the band is resonant on your antenna? What type of instrument are you using to measure your SWR? If you are just using the meter on the radio, try and get an independent source (SWR/WATT Meter) Panel meters are sometimes inaccurate. Wat type of mount are you using? (mag mount, surface mount? NMO?) If you can, try and fill in some of the blanks. Thanks, Dale K8TS
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Hi Dale!
I have the Shark Mini 20m antenna. I am trying to work with the lower portion of the 20 meter band. I have no problems adjusting the length of the whip to find the bandwidth i want to operate in (CW portion). I just cant get the swr to come down. I have attached an image from my VNA.
John,
Well about 2:1 is not a bad swr. Remember the “mini” is 36” and the standard is 44”. While it sounds like you have perfected your ground you did not say where your whip is mounted, and as Doug mentioned, what type of mount you are using. My guess is that there is some part of the truck…like the cab, interfering or in direct line with your antenna. Also, depending on your mount type, you may not be getting the ground from the mount to the body of the truck. For example, if you are using a lip mount, you may need to ensure the screws contact the body and not the paint, and of course a magnetic mount will not work as good as a lip mount. I have used hamsticks for decades but also use an antenna tuner on my mobile HF radio. Like any antenna, you may want to consider adding an antenna tuner. From your VNA photo it is clear that you have optimized the antenna for 14.055. Remember that 14.055, a lower freq, requires a longer antenna than say 14.250 which is a higher freq. You also didn’t tell us if you are making contacts or if your radio works with the 2:1 swr. My guess is that your antenna approximates 1:1 closer to the ssb portion of the band. 1:1 may be unreachable. These are great antennas and I have worked dx all over the world with them. Hope this helps.
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Harry,
I am currently looking to run my QRP-Labs QMX radio. 2:1 is really the top end for this little radio and it sensitive finals. I have no problems adjusting the antenna up to the SSB portion of the band, But the SWR does not change. I can shortent the whip for 14.250, but the best i get is 2:1. The differnce in antenna length from CW portion to SSB portion in only half and inch of adjustment. I have attached a photo of mounting. Note: I have sanded the paint off inside the tool box, bonded the toolbox to the bed and insured continuous bond through frame and cab. I understand that 2:1 isnt “bad” but it is not good either. Especially running QRP….
John, sadly, your antenna is probably seeing your toolbox also. You would perhaps see better results if you could move the antenna away from the tool box. We carry a wide selection of fender mounts which would get your antenna away from metal obstructions. We carry a large selection of fender mounts. I would recommend one but I do not know the manufacturer of the Tacoma. Please use the search “fender mount” to find the correct one for your vehicle. Wish I could do better, Harry gave you some excellent suggestions, thanks for checking with us. Dale K8TS
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I agree with Dale. The antenna is too close to the box. How about the intellitron trimag mount ZIN-MM-2106T. Big enough for the largest antennas. Not sure if your box lid is all the width of your bed ? My box only opened on each end so it was a great choice. Some things to think about. I noticed you didnt have Coax seal on the connector. We sell that, too!
SKU:
ZCB21018
Good Stuff~
73
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