BAD MSG: <[email protected]>] (fwd) essage-ID: <[email protected]> X-Authentication-Warning: europe.std.com: daemon set sender to treg-approval using -f Precedence: bulk List-Post: [email protected] Date: Fri, 27 Sep 96 16:14:18 +0000 Mime-Version: 1.0 Content-Type: Text/Plain; charset=US-ASCII X-Mozilla-Status: 8011 Content-Length: 1620
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 >
