"Geoffrey S. Mendelson" <[EMAIL PROTECTED]> made an utterance to the drakelist gang ---------------------------------------------------------------------- On Tue, Jul 12, 2005 at 11:22:36AM -0000, Bob Henderson wrote:
> I returned the R-4C to the shack last night expecting the interference from > BC signals on 20 & 40m to be thing of the past BUT they were as loud as > ever. On 20m still peaking within a few degrees counter-clockwise rotation > of the preselector and on 40m peaking within a few degrees clockwise > roatation. My heart sank. I left the receiver set to 40m with the > preselector peaking the interfering signals i.e that few degrees clockwise > from the 40m peak and I retired to bed. Bob, I've been following this since the beginning, but am hazy on a few details. My first question is there an antenna connected to the radio when you hear the signals? Ignore for now the '570 and '930. Disconnect the antenna and if you can short out the antenna connector. I ask to make sure they are not sneaking in from somewhere else. Then connect a good DC ground and check again. Still quiet? If not, you have either leakage from an external source, or a bad connection acting as a rectifier and detecting the AM signals. If the receiver is in a metal case, as IMHO it should be, make sure the case is properly grounded and if the chassis is not hot (I'm not familiar with the receiver in question, so I thought it best to ask) make sure the case is grounded to the chassis. If it is, then connect up your antenna.Come back? Hopefully they did not. but they probably did. If you have an antenna tuner in a metal box, then connect the antenna to it and a good DC ground to it. Tune for maximum noise on 7020. At this point if you have another receiver connected instead, it should hear almost nothing of the AM stations on 7020 or their actual frequencies. If it does, then there is probably a SW relay of them near you and you are picking a reflection of it up and confusing it with the same stations AM broadcast. Assuming there is nothing, Connect up the R4C without the preselector. What do you get? Please report. BTW, since you have a '570, you probably should do the AM broadcast mod on it. This involves moving a jumper (like on a computer card) and gives you great medium wave sensitivity. Remember that ground waves travel long distances over water. If I had a decent antenna (I don't) in the summer near sunset I could probably work you on 2m. :-) Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel [EMAIL PROTECTED] N3OWJ/4X1GM IL Voice: (077)-424-1667 IL Fax: 972-2-648-1443 U.S. Voice: 1-215-821-1838 VoN Skype: mendelsonfamily. Looking for work as a CTO or consultant in handheld gaming, large systems development, handheld device construction, etc. Support amateur (ham) radio, boycott Google!!! ---------------------------------------------------------------------- On Behalf of "Geoffrey S. Mendelson" <[EMAIL PROTECTED]> Submissions: [email protected] Unsubscribe: [EMAIL PROTECTED] - unsubscribe drakelist in body Hopelessly Lost: [EMAIL PROTECTED] - help in body of message Zerobeat Web Page: http://www.zerobeat.net Brought to you courtesy of TLCHost.net http://www.tlchost.net/ ----------------------------------------------------------------------
