Jack, Thanks for your suggestions. I'll give it a try and let you know the results.
Duane On Fri, 27 Sep 1996, Jon D Curtis wrote: > From: Jack Marshall <[email protected]> > To: [email protected] > Subject: Re: Bowmar Return Loss Measuring Test Set > In-Reply-To: <[email protected]> > Message-Id: <Pine.SUN.3.91.960927101813.12834A-100000@homer> > Mime-Version: 1.0 > Content-Type: TEXT/PLAIN; charset=US-ASCII > > Duane, > > I've used a Wiltron 9041 (also no longer available), and I found that > when using a complex reference, I got much better results (i.e. closer to > the real return loss) by calibrating with a short circuit, rather than an > open circuit. Using an external oscillator required callibration at each > frequency, by shorting the input (where Tip and Ring of the EUT would go) > and adjusting the oscillator amplitude until the return loss reads zero. > Then replace the short with the EUT. Hope this helps. > > Jack Marshall > Bay Networks > > On Thu, 26 Sep 1996, Duane J Marcroft wrote: > > > Treg'rs. > > > > I have Bowmar Return Loss Measuring Set, Model 481A. Can anyone give me > > an idea where I might obtain a copyof Operators Manual and/or a service > > manual for this device? I've tried contacting Bowmar in Acton, Mass,where > > it was built, but they are no longer there. > > > > I purchased it a year ago for a low price and it does not look like it was > > ever used. I can use it in all modes except with an external complex > > impedance and external oscillator. It would be very nice to use it in > > these modes to confirm the calculated return loss measurements of the > > DAA's I'm designing for various countries. > > > > Thank you in advance. > > > > Regards, Duane > > > >
