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KenW <ken1943@invalid.net>: Dec 04 09:09AM -0700 On Fri, 4 Dec 2020 11:00:07 -0500, Ralph Mowery >good. It is not just one ham receiver,but several.   >My theory is that the portable receiver is matched for a high impedance >short antenna, where the ham receiver is matched for a 50 ohm antenna.   Amateur Radio equipment is built to favor ham frequencies and not broad banded like your general equipment.     KenW

Ralph Mowery <rmowery28146@earthlink.net>: Dec 04 11:00AM -0500 While not really a repair,but more of a question.   Why is it that I have one of the portable receivers with a whip antenna that is about 2 feet long and can receive very well the short wave stations, but my ham receiver with a couple of feet of wire on the back receives almost nothing. When I hook the normal antenna to it, it receives vey well. The signal generator shows the sensitivity is very good. It is not just one ham receiver,but several.   My theory is that the portable receiver is matched for a high impedance short antenna, where the ham receiver is matched for a 50 ohm antenna.

OJ Oxford <bestnet@none.com>: Dec 04 08:36AM -0500 My former post was on the unwanted heating up of a cigarette lighter and it was determined that there was too much resistance in such a connector, so switched out to the XT60 based mainly on Jeff Liebermann's recommendation. I initially had great difficulties with my various soldering irons on hand heating up both the connector and the 12 ga copper wires enough to get an acceptable connection, so proceeded to order a brand new 60 watt temp controlled iron and some flux. Well, I'm happy to report that all is well. I have been pleasantly surprised by how well the combination of the iron and flux are working and all connections, while still delayed a bit, are being satisfactorily made and I no longer have lack of connection, melting, or cold solder concerns. Oh, and I have been working with silver solder too as the standard had not yet arrived.   Apparently, my other irons on hand either didn't have the correct tips, were too old to heat up correctly and/or lacking the additional flux all worked to disadvantage. I must say that this 60 watt iron heats up faster than any of my other irons. It is a pencil type and ready to go in about 15 seconds, where my other pencil units always took several min.   Thanks again to the group for setting me straight.

Fox's Mercantile <jdangus@att.net>: Dec 04 09:16AM -0600 On 12/4/20 7:36 AM, OJ Oxford wrote: > Thanks again to the group for setting me straight.   Not all of us give bad advice just to see our name in print.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Jeff Liebermann <jeffl@cruzio.com>: Dec 04 07:54AM -0800 On Fri, 4 Dec 2020 08:36:01 -0500, OJ Oxford <bestnet@none.com> wrote:   Thanks for the update. Some minor comments.   >I initially had great difficulties with my various >soldering irons on hand heating up both the connector and the 12 ga >copper wires enough to get an acceptable connection,   More correctly, those were soldering guns, which I consider to be a really bad idea for soldering XT60 connectors.   >I have been working with silver solder too as the >standard had not yet arrived.   Silver alloy solder melts at about the same temperature as 63/37 lead/tin solder. However, 50/50 melts at about 25C higher temperature. Be sure to adjust the temperature of your new soldering iron depending on which solder you are using. Also, try not to mix solders. You can mix 50/50 and 63/37, but not either of these and lead free RoHS (tin/silver/copper) solders. I'm not sure about mixing with silver solder. If you get a solder connection that is dull and not shiny, clean off as much of the solder as possible and start over with solder and flux until you get a shiny connection.   >I must say that this 60 watt iron heats up >faster than any of my other irons. It is a pencil type and ready to go >in about 15 seconds, where my other pencil units always took several min.   My guess(tm) is the lack of a temperature controlled soldering iron was the main contributor to your soldering problem because the copper wire was drawing away all the heat from the joint.   If your other pencil irons (or soldering guns) took several minutes to heat up, they were probably not temperature controlled. When I learned to solder about 65 years ago, all I could buy were non-temperature controlled soldering irons. At the time wood burning art kits were popular. Make a "painting" with a piece of wood and a wood burning iron. Later, I graduated to essentially the same irons, but made for electronics. It was perhaps 20 years later, that I was introduced to a proper temperature controlled soldering iron. The difference was amazing. The temperature controlled iron (Weller TC-201T) had a "magnastat" thermostat in the iron to control the temperature. Unlike the non-temp controlled iron, the iron could produce far more watts than needed to heat the tip, and regulate the temperature with the thermostat. The non-temp regulated iron had to dissipate the exact amount of watts necessary for the tip to stabilize at the desired temperature.   Another advantage is a temp controlled iron will not cool down (much) when the tip is touched to the work. The thermostat senses the drop in temperature, and increases the current to the heating element to compensate. Such a temp drop is likely when soldering large gauge copper wire, which acts as an excellent heat sink to draw heat away from the joint.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Stu jaxon <stankowalski02@gmail.com>: Dec 03 03:47PM -0800 > > > Model number means nothing on these "RCAs". Post the board numbers. > > rca fre01m3393lna35-a2 main board.. power supply re46hq0602-20141105 > Most of that series has a corrupt UL2 eeprom. I have the .bin file if you have a programmer.   nope, no programmer. is there a way to test the eeprom pins with a scope or multimeter???

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