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![]() On Mon, 18 Dec 2006, Mike Andrews wrote: Some friends and I have been looking into making antennas for 70 cm. and higher frequencies, but we don't have an MFJ-269; my MFJ-259 tops out at 175 MHz. I _do_, however, have an SWR meter that supposedly works up to 500 MHz( and maybe higher), and an HP 8640B that is good to about 1.2 GHz. If the SWR meter is sensitive enough, could I get at least ballpark SWR values using the 8640B as a source, You did not say what an 8640B is. Signal generator? Transmitter? Power out? Main thing is to get the "forward" power to read something on the meter (preferably full scale, but even if you get half or quarter scale, then you are able to get a rough idea of usabiltiy of the meter). Then see what it shows on the "reflected" scale. Figure ver roughly if the reflected power is half the forward (regardless of the actual location on the meter scale), then you have about 3:1 SWR. Turn the meter around to get an idea if the diodes (and associated circuitry) are well matched for forward and reflected. I have used a number of el-cheapo CB SWR meters even up on two meters and they work surprisingly well, even more sensitive than ham SWR meters for VHF-UHF, and not that far off of what the ham SWR meters report, and so are good for handie-talkie measurements. So, yes, you should get useful ball park figures. running the signal through the SWR meter to the antenna? Or am I way off in left field? -- Mike Andrews, W5EGO Tired old sysadmin |