Silence? I wonder why there is a silence after I announced that "Proper interference immunity (RF integrity) test MUST be made with a 2nd or more TX at specific interference prone channels at specific spacing in relation to the on channel TX and Rx." Fun? Neither do we derive fun on preflight range test, but we do it anyway, nor it was fun to maintain a RF air traffic channel board, we do it anyway. If fun is reduced to flying, we can consider free flight. We are here to derive fun (or joy) from maneuverability to accomplish our goal supported by quality "control" and "handling". Same applies to driving (controlling) a high performance sport or racing car. In that sense, control quality is one root factor to reach those fun and joy. if not by goal. The other root factor, as we know, a quality plane. Quality is about the desired sensitivity, response and dynamic range, these terms apply to both plane and Rx equally well. There is no such thing as up the plane quality and forgo control quality. I hope we do not call that Fun. Making close door conclusion about Rx evaluation problem is well suited for its originator but the general public. Ground range test procedures designed for RC field test without any test bench equipment was published in RCSE a number of times. A short note about open field test for Rx quality. A straight line jointing two TX spaced 33 meter apart on identical wooden pedestal. Walk your RC plane along such line and mark Rx-TX* spacing at the threshold of servo buzzing. (*nearest). Continue same procedure for next candidate. One TX will be a on-channel the other TX(s) will be channeled at any interference prone channels one at a time. Interference prone channel relative to on-channel (N) is ... +/-1ch, +/-(11 to 12)ch, +/-(22 to 23)ch, or any two 20kHz spacing channels A and B that satisfy N=(2A-B) or (2B-A). The two test TX will be the same model is require for consistent result. YK Chan Seattle. ----- Original Message ----- From: Michael Neverdosky <[EMAIL PROTECTED]> To: RCSE <[EMAIL PROTECTED]> Sent: Tuesday, July 25, 2000 4:21 AM Subject: Re: [RCSE] Fw: IPD PCM PPM > We don't know where the improvement comes from. It could be a more > sensitive receiver, better processing or both. > > For flying RC models it doesn't much matter as the link between the > sticks and the flying surfaces is the important one. The stuff in > the middle is not so important. > > I can do tests to check the RF link but this requires looking at the signal > at the detector (discriminator or other) inside the receiver. There are > also tests for selectivity, dynamic range, and a host of other things > that influence real world performance, but who cares? I cannot buy a > RF section separate from the processing section from any of the RC > equipment makers. I can only buy a complete receiver so that is what > is most important to test. > > Of course you can put the receivers on the bench, hook your SINAD meter > to the descriminator, run the transmitter through a calibrated attenuator > and find out the sensitivity. While you are there you can test everything else > but it still doesn't help much as it does not accurately reproduce the > evnvironment where the radio will be used. > > I have ordered a MX system with IPD and will install it in a plane and > see how much fun it is to FLY and if it has any problems with interferance > in the places that I fly. > > Unscientific, yes, but relevant and a lot more fun. I spend way too much time > at the electronics bench now and need more time flying. > > :-)) > > I still think it is useful to discuss the ins and outs of the radios even if > I am not going to build my own (although I might) just as I enjoy reading > the process Joe W. uses to optimize a plane design even though I am even less > likely to design my own world class sailplane. My sailplane designs usually > win the "ugly" contest. :-)) > > As long as we are having fun. > > michael N6CHV AMA 77292 > > YK Chan wrote: > > > > Erine's ranging observation to those candidates can be interpretate as > > such that the perceived IPD performance is actually a result of 1.6dB > > better in RF sensitivity instead of IPD in effect. Rx cousins of > > different post-detection processing (IPD, PPM, PCM) do not necessary > > hold equal RF sensitivity, until proven and accepted as identical > > among them. I am not convince at all that IPD has contributed the > > difference. > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
