But, be aware that there are two types of these meters: 1. those that have internal thermocouples and are ready to hook right into the circuit. 2. those that use an external thermocouple which may or
It is interesting to recall that the Collins and Drake rigs, noted for excellent noise blankers for the times, both used separate 40 MHz receivers to obtain the noise signal through a wide passband a
Ron, do you feel that having narrow selectable roofing filters in the Argo V would improve it? How well does the present design deal with multiple S9+30 dB signals "near" your desired S1 signal using
Thanks for the info, Ron, but don't go to any trouble making .wav files. I have a friend with an Argo who would let me audition it if I became interested in getting one. What I was trying to understa
A resistive attenuator in the antenna input will do about the same. Anything that lowers the front end gain or input signal level will boost the IMDDR3 by the same amount. inside the roofing filter i
Jack, I wonder if some unintentional typos got into your posting. Adding any loss ahead of the receiver *increases* the noise figure by the amount of the loss in dB and raises the minimum detectable
I am late getting in on this one, but if the question is how to relate 5 mV of voltage to a power level of -67 dBm, one answer is 125.3 kilohms. <:} I have no idea what the original question was but
Pete, I think that you are may be confusing the dBm with the definition of the decibel and how meters are calibrated and referenced.. It is always true, by definition, that 0 dBm represents a power l
Mark, I think that you may still have a problem there. The dBv reference is defined to be one volt. Thus 5 mV relative to one volt expressed in dBv would be dB = 20 log (5x10^-3)/1 = -46 dB Since we
Yes, Mark, you have identified the whole point of this discussion. Good on you! The notion that "the input should be 5 mV or -67 dB" is meaningless in itself as I have tried to demonstrate with the f
Ken, it sounds like you might be thinking of the dBu, which is a dB reference widely used in the professional audio world. Its definition is a product of the National Association of Broadcasters. At
Thanks very much, Paul, for adding some background to my previous posting(s). I was beginning to think that I was preaching to an empty church from the lack of responses! <:} Now, if we can just get
Right, Tom - many references and a lot of confusion when people start mixing them. I notice on my 606A that while the 0 dB scale on the *attenuator* is linked to the 0-0.3 volt *meter* scale, when th
Eric, I once challenged ARRL on "bauds" and they sent me a copy of some ITU spec that used that term. They argued that if it is proper to use "Ohms" and "volts" then it is equally proper to use "baud
What happened is that IBM is no longer a player in the PC building and selling market . . . they gave away the store to Microsoft and Intel in order to "expand the market." It expanded right past the
I'm not sure that it buys much, Mark,unless there is a problem with the rig. But, it is sorta like a fine car and its speedometer: you really expect it to read "right on the money." My Icom PRO2 usua
Glad to be of help, Bill - I devised this method a couple of years ago and most who have tried it seem to appreciate its simplicity, ease of use and seeming accuracy. I should have mentioned, althoug
That is the purpose of measuring the WWV audio tone frequency in AM mode, Dan. That takes dial calibration out of the picture. If the measured tone frequency is in error, then you are correct: the so
Bill, make sure to use the lowest possible signal level into the program for best accuracy. The trace should be clearly visible but very little background noise should appear. Overdriving will introd