Yesterday, a reader wrote me:
Dan, do you think I need an SWR meter for VHF/UHF? My maximum output power would be 5 W. I am having difficultly find a meter that can measure such a low wattage. Down to 2w. Only MFJ seems to have something available, and their quality is hit and miss. Thanks! 73’s
I replied that I didn’t think that he really needed a VHF/UHF SWR meter, especially if he wasn’t planning to design his own antennas. You should be able to tell if you’re having antenna problems by noting the output power of the radio. Most, if not all, modern radios will throttle back the output power if there’s a big mismatch.
Just for kicks, though, I Googled “low-power VHF/UHF SWR meter.” A couple of the link proved interesting:
- Nissei RS-40 VHF/UHF Power/SWR Meter. This item got mixed reviews on eHam.Net. Based on the reviews, I’d probably stay away from it.
- Fox Delta Micro Controller LCD VHF/UHF SWR Meter . This looks like an interesting project. It is a project, though, i.e. something that you’ll have to build.
- SWR meters for low-power use. This isn’t something that you can buy, but it points to a couple of articles previously published in QST that show how to build a return-loss bridge. From those measurements, you can calculate the SWR (or just tune the antenna for the lowest return loss).
The VHF/UHF SWR meter that I have is an Opek SWR-6 (http://www.universal-radio.com/catalog/meters/0988.html). I think it cost me about $70. I have never really checked its calibration, nor do I have any equipment to really do so, but it seems reasonably accurate. Unfortunately, it’s no longer being manufactured.
Do any of you have a suggestion for us? What do you use, if anything to measure SWR at VHF/UHF?