RF power and VSWR meter


Posted on Jul 2, 2012

The Inter-Power SWR-5 - upper right - `isn't worth a penny`. Got it from a mate to use with a beacon, but I burnt it out with only 3.5-4W morse signal on 70cm. Removed the bridge and installed my own pick-up line (suggested by LA8OJ) and now it is fb for VHF/UHF. The old Hansen, Reace or whatever make `SWR-meter from 1968 (from J. B. Lowe) or later has a relatively good bridge, it works fb on 2m - provided careful operation, sensitivity is very good on 2m! It is easy to destroy, but works fb with level down to 10mW, have used it on 180-190MHz to test TV-receiver antennas using Wavetek Model 3001 signal generator, but mounted N-connectors to make it look sufficient professional at work, see next note.


RF power and VSWR meter
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The Inter-Power SWR5 was renovated and since the meter and box was so nice looking I decided to keep it and remove the useless bridge. Mounting wire is pulled under the braid for a length of 40mm. It is easier for the old type RG8/U, where the braid often is somewhat looser than for RG213/U. I wouldn't think about using RG214/U! It was some struggle to mount the bridge, and solder in the right order since it is just as must space as you need. Another application of the same technique. It is so easy to build pick-up bridges, it is just fun. Here is my 2m line - permanently inserted between the PA to antenna. Suppose RG8/U type coax-cable is better than RG213/U since the braid may be somewhat loose, but must not be dark and corroded.




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