Date: Thu, 2 Jun 94 04:30:16 PDT From: Ham-Ant Mailing List and Newsgroup Errors-To: Ham-Ant-Errors@UCSD.Edu Reply-To: Ham-Ant@UCSD.Edu Precedence: Bulk Subject: Ham-Ant Digest V94 #167 To: Ham-Ant Ham-Ant Digest Thu, 2 Jun 94 Volume 94 : Issue 167 Today's Topics: Grid Dip Oscillator or Noise Bridge? Send Replies or notes for publication to: Send subscription requests to: Problems you can't solve otherwise to brian@ucsd.edu. Archives of past issues of the Ham-Ant Digest are available (by FTP only) from UCSD.Edu in directory "mailarchives/ham-ant". We trust that readers are intelligent enough to realize that all text herein consists of personal comments and does not represent the official policies or positions of any party. Your mileage may vary. So there. ---------------------------------------------------------------------- Date: 2 Jun 1994 10:53:16 GMT From: ihnp4.ucsd.edu!agate!usenet.ins.cwru.edu!news.ysu.edu!malgudi.oar.net!infinet!wvanho@network.ucsd.edu Subject: Grid Dip Oscillator or Noise Bridge? To: ham-ant@ucsd.edu Jerald Pendleton (jerald@wrs.com) wrote: : The budget is looking good for a new toy.... : I am thinking of getting a piece of equipment to help me tune my : new (and heretofore unerected) HF antenna and I debating the : merits of couple of devices, : MFJ is selling two devices that I think are a grid dip oscillator : and a noise bridge [If i've got this wrong, please correct me] Previous postings have advised you to get an antenna tuner, instead. I can't disagree with that advice if you are confining your experiments to an antenna, only. But if you plan ANY other kind of radio work, some method of measuring resonant frequency is invaluable, and a GDO is nearly essential. What nobody has pointed out, yet, is that an MFJ SWR Analyzer, Model 249 or 259, can also be used as a GDO (strictly speaking, it is not one, but it works exactly like one). An article by David Barton, AF6S, "An Accurate Dip Meter Using the MFJ-249 SWR Analyzer" in QST, Nov 1993, showed how. A Digest of that issue was posted just this week on this newsgroup. I have used GDOs for 50 years, and until the MFJ analyzer came along, they all had one inconvenient feature. The frequency dial always was necessarily very coarse and to measure frequency accurately, one had to use a counter or frequency meter, or else listen to the oscillator signal on a receiver and compare it with other signals on the band. The MFJ unit has a built-in frequency counter and the user always knows the exact frequency with high accuracy. Boy, does that save time! I have no complaints about the quality of the MFJ-249 I have. I have no connection, whatsoever, with them. 73, Van - W8UOF wvanho@infinet.com * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * It ain't wot ya don't know 't gets ya into trouble. * * It's wot ya know 't ain't true. - "Mr. Dooley" * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ------------------------------ End of Ham-Ant Digest V94 #167 ******************************