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We found that the negative lead from the Astron power supply was internally grounded to the chassis and ultimately to the mains power outlet and back to the electrical panel and to our grounding copper pipe. Researching Astron's technical documents, it was found that this terminal is normally not grounded but there have been a few from the factory that were internally grounded for special circumstances. According to factory representatives and a factory schematic, this terminal should not be grounded. In actual practice, I can state that a power supply should NEVER be grounded. Portions this high current was being passed through a very small power cord conductor and to the electrical box. This can and does create a ground current loop and will cause a problem. The negative or possibly the chassis of a unit can then be tied to a "Star" grounding topology and ultimately to the main grounding bus bar at the destination unit. The Astron unit was pulled, dismantled, examined and corrected. FYI, never allow the power source to be internally grounded. Thank you, Gordon Patenaude WA0WSR

Hi, I'm planning out a 2m repeater installation for the local club here. The repeater's antenna is going to be on top of a two-story building. I'm curious to know your opinion on a dual antenna setup. That way, we'll save a lot by not having to use a duplexer. On the other hand, I am not quite sure if that's going to mess with the repeater's coverage or reception. We could put the antennas about 15-20ft far from each other. I was thinking about a Comet GP9 for TX and a Discone for RX. The antennas will still be on the same roof but on opposite edges. The repeater in question is an SLR 5700 if that makes any difference. 73, Sepehr N6IRN

To add 6 meters to the portable antenna discussion and after reading at least most of the high band/ UHF portable antenna discussions, this is what I found just playing around with a foot long top loaded 6M rubber duck antenna (I believe made by Antennex a number of years ago) and a 19 inch long telescopic antenna attached to an antenna analyzer approximating 6M &2M portable usage.... Compared to a 1/4 wave 19" whip, the top loaded foot long whip SWR bandwidth is way too narrow to cover multiple frequencies and keep the SWR below 2, being something under 500KHz BW, and that is under ideal conditions with either a 1/4 wavelength wire dangling down to make the other half of the antenna, or the portable metal belt clip making contact with a cabinet or other large metal object, or a bare hand making contact with the portable belt clip metal. The 1/4 wave whip with aluminum foil wrapped against the antenna connector shield and extending beyond the borders of the insulated case on the analyzer, and bare hand on the foil to simulate an HT, SWR varied from 2.5-4 depending on frequency , but the bandwidth of the full 1/4 wave whip was way beyond any SWR changes from local factors. Our conclusions.... All HT transmitters need to be able to tolerate very high VSWR most of the time. A 6M rubber duck is extremely inefficient and definitely requires a counterpoise, even with top loading. Basically forget using them without an external antenna separated by coax unless very close range! Even 2M portables should have a counterpoise to the antenna. See 2 pics of our set up. John o

It appears Congress may be in favor of this bill for amateur radio. I'm not a lawyer so some of the language was a little too much for this old guy. Now, they just need to include wording about amateur radio remote stations (repeaters) a rental break, such as with the USFS and BLM, etc Input welcome. -- - Regards, Karl Shoemaker To contact me, please visit SRG's web site at http://www.srgclub.org for the current email address.

Anyone have this unit? I'm researching to see if it's junk or can really work in the field. https://www.gqelectronicsllc.com/comersus/store/comersus_viewItem.asp?idProduct=5678 -- - Regards, Karl Shoemaker To contact me, please visit SRG's web site at http://www.srgclub.org for the current email address.