- Mobile anyennas for six and two meter bands - 2 Updates
- Sherwood RD-6108 receiver turns on and off randomly. - 4 Updates
- Blown Electros - 5 Updates
| captainvideo462009@gmail.com: Sep 18 04:07AM -0700 I plan on installing my Yaesau FT 867 in my car. The car was a former state police vehicle and so holes were already cut in both the middle of the trunk and the middle of the roof. I have a bunch of NMO type antenna bases around here that cover these frequencies and I would like to use these antennas for this. I have used these antennas before but only for one specific frequency. It has been my experience that these antennas tune rather sharply. Since both of these bands are 4 MHZ wide what frequency should I cut the antennas for? Center frequency would be easy but wouldn't an antenna cut for 52 MHZ have very poor SWR when used at 50 MHZ? The rig has both low and high band outputs. I'm not sure what I should do. Thanks for any input on this. Lenny |
| Fred McKenzie <fmmck@aol.com>: Sep 18 12:36PM -0400 In article <f899c883-5185-4ac3-95b2-33c2d3e6e9e1@googlegroups.com>, > Center frequency would be easy but wouldn't an antenna cut for 52 MHZ have > very poor SWR when used at 50 MHZ? The rig has both low and high band > outputs. I'm not sure what I should do. Thanks for any input on this. Lenny Lenny- I would get the matching LDG auto tuner. It would work on HF through 6 Meters. That way you could cut the 6 Meter antenna for mid-band and let the tuner match other frequencies. This assumes the antenna needs tuning. I would check it to see how far off it is at band edges when tuned to 52 MHz. If you are lucky, the FT-867 can tolerate the extremes. Fred |
| dplatt@coop.radagast.org (Dave Platt): Sep 17 11:30AM -0700 >but it happened again 2 hours later. Now it clicks off when on from >anywhere from 2 seconds to hours. Is there a common fault for this >receiver causing these symptoms? Thanks. Chuck Check for current leakage in the areas around the on/off switch. Some decades ago I had a Macintosh II which had a habit of turning itself on without human intervention - usually in the morning. I eventually traced the problem to the keyboard. The Mac II uses a "soft" power switching setup, where the keyboard power switch pulls one of the ADB-cable lines down to ground. This sense line has a very high source impedance, and it didn't take much current leakage to ground to false-trigger it. The Mac II was in a spare bedroom that got quite cold at night during the winter (the place we were renting had a lousy heating system and no insulation). In the morning, my wife would take a shower, humid air would flood the back of the house, some moisture would condense inside the cold keyboard case, and a few microamps of current would leak across the switch contacts. BONG! I cleaned the keyboard's PC board in the area of the switch with some alcohol, coated it with something insulating (I think I used a thin film of my wife's acrylic nail polish) and the problem went away. So, I'd suggest inspecting the power switch and the PC board around it. Possibly some old flux, or the dreaded "yellow glue" on the board has become conductive with age. Clean it all up thoroughly (careful scraping, flux-remover spray, etc.), dry well, and apply a conformal insulation coating of some sort, and see if that resolves the problem. Looking at the manual for the RD-6106 (which may be similar) - this receiver does seem to have a "soft" power switching system, where the main AC voltage can be controlled by both a "hard" switch, and by a relay system driven from the control logic. The control logic then looks at a "standby" pushbutton... this is a low-level contact closure and seems to be tied in with the main keyboard scanning logic. So, a contaminated "standby" PC board / assembly might be at fault. |
| Chuck <ch@dejanews.net>: Sep 17 10:02AM -0500 I don't have a service manual for this receiver but I checked the 6V standby voltage and the 15V line from the standby power supply and they both are at the correct voltage and have low ripple. I've heated and cooled the boards with no change of symptoms. The problem began by the receiver turning on in the middle of the night. Reset the micro but it happened again 2 hours later. Now it clicks off when on from anywhere from 2 seconds to hours. Is there a common fault for this receiver causing these symptoms? Thanks. Chuck |
| Chuck <ch@dejanews.net>: Sep 18 10:50AM -0500 On Mon, 17 Sep 2018 11:30:08 -0700, dplatt@coop.radagast.org (Dave Platt) wrote: >looks at a "standby" pushbutton... this is a low-level contact closure >and seems to be tied in with the main keyboard scanning logic. So, a >contaminated "standby" PC board / assembly might be at fault. Thank you for your input. I had removed the conductive glue from the boards with no improvement. I've seen the leaky tact switch faults on tvs, but I didn't think of it in this case. Will disconnect it and see if the receiver stays on. |
| Chuck <ch@dejanews.net>: Sep 18 10:53AM -0500 On Mon, 17 Sep 2018 08:30:14 -0700 (PDT), "pfjw@aol.com" >Silly suggestion - does a piece of black tape over the IR sensor help at all? I suggest because I am seeing lots of "smart house" stuff starting to interfere with some legacy equipment out there. You might also isolate the remote as some of the touch-pad contacts may be aging and making random contact. That is to get past the obvious. >Otherwise, I would trace out the on/off circuit and look for a bad capacitor on in that lot. This unit is approaching 18 years old, or so, about the time these tiny little electrolytics start to fail. >Best of luck with it! Yes, I covered the IR window but I didn't disconnect the IR receiver which have caused weird tv symptoms. Thank you for your suggestions. |
| "J.B. Wood" <arl_123234@hotmail.com>: Sep 18 06:18AM -0400 > Sure. I will not suggest that it happens "all the time", but I have had a couple of big, honking (5,000uf @ 80V) coupling caps go off like Roman candles, leaving no other marks and giving no warning. These things had little rubber plugs on top - and the only visible evidence after the show was that the plug was missing. Made in Scotland, as it happens. > Peter Wieck > Melrose Park, PA Hello, and if it isn't Scotch, it's craaaap! Sincerely, and with apologies to the creators of a very old Dan Aykroyd SNL sketch), -- J. B. Wood e-mail: arl_123234@hotmail.com |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Sep 18 04:39AM -0700 On Tuesday, September 18, 2018 at 6:18:21 AM UTC-4, J.B. Wood wrote: > Hello, and if it isn't Scotch, it's craaaap! Sincerely, and with > apologies to the creators of a very old Dan Aykroyd SNL sketch), Blended scotch is not fit to clean toilets. Balvenie Double-Wood is quite nice, however, for a mid-range single malt. Peter Wieck Melrose Park, PA |
| "J.B. Wood" <arl_123234@hotmail.com>: Sep 18 09:15AM -0400 > Balvenie Double-Wood is quite nice, however, for a mid-range single malt. > Peter Wieck > Melrose Park, PA Bien sur, Peter, and offerings from Macallan, Glenfiddich and Glenmorangie ain't bad either, IMHO. And there's always that smokey peat essence to be had in Sam Adams' Scotch Ale as well. I screwed up - I should have said "Scottish" vice "Scotch". OK, back on topic. Sincerely, -- J. B. Wood e-mail: arl_123234@hotmail.com |
| Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Sep 18 09:35AM -0400 On 9/18/18 9:15 AM, J.B. Wood wrote: > peat essence to be had in Sam Adams' Scotch Ale as well. I screwed up - > I should have said "Scottish" vice "Scotch". OK, back on topic. > Sincerely, My grandfather was born in a peat hut on the Isle of Skye. To the end of his days he insisted on being called a Scotchman, not a Scotsman. I cordially dislike whisky in all its flavours. Cheers Phil Hobbs |
| "pfjw@aol.com" <peterwieck33@gmail.com>: Sep 18 08:12AM -0700 I remember my high-school English teacher explaining that Seltics lived in Boston and were mostly over six (6) feet. Keltics, on the other hand, live in Ireland, Scotland and Wales, and parts of Brittany and come in all sizes and shapes. Scotch was for drinking, Scots were people, scotties were dogs (we have one), and Scottish was the generic. His favorite phrase, which I use on occasion was: "I know what you said, but I am still trying to discern what you mean." He was a stickler, to this day, whenever I am asked "Can I.... ", my very nearly instant reply is: "I don't know, can you?" Whenever I meet classmates, now over 50 years later, we still drop that line on occasion. Peter Wieck Melrose Park, PA |
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