Are you sure your 50uH choke is doing its job? 9t to get 50uH suggests ferrite witout a gap. IN which case FDC thought the winding will be saturating the ferrite, driving it into non linearity an
The other thing about that circuit that is wrong is the power out specification for the turns ratio / loading resistance. For a single ended PA, Pout max = Vdd ^2 / 2 / RL. With a 9:1 (3:1 turns) t
The scopematch circuit looks reasonable. Arithmetic is correct (as an aside, I always group constants together for calibrations like that. Measuring peak to peak across a 50R load, power then be
Well ... Using exactly the values in the filter circuit diagram, 50R transforms through the filter to 48.5 - j2.86 (Ret Loss = 30dB, VSWR = 1.07) [Using GM3SEK's original Netcalc prog.] So that
Yes Try anything and try to work out what is happening. But first of all, he needs to know what power being deliverfed into a 50 ohmsload is seemingly higher than it 'can' be. The Vdd^2/2/Rl cann
Sounds more like feedback. RF feeding back into the driver stages. The LF component you see is, perhaps, a beat between generated RF and oscillatory RF due to feedback. Or feedback itself oscill
Seems an odd choice of driver chip. A high/low side driver used in a non-bootstrapped mode to drive two low-side FETs How about one of the normal FET driver chips - picking out one I've used in the
When I said bias half way, meant half way between the two logic threshold limits. Ie mid way between 1.3V (upper limit of guaranteed '0' and 2.4V (lower limit of guaranteed '1') so bias at 1.8V Not
There something odd _ I've just checked the data sheet http://ww1.microchip.com/downloads/en/DeviceDoc/22022b.pdf for the MCP1404 you are using (I used the MCP14E4 slightly later I think and the
In that case you have a very odd MCP1404. That looks like a typical CMOS threshold where the level is a fraction of the Vdd. Often something like 0.45 Vdd ( very roughly. CMOS guaranteed thre
I've just noticed that Emails to this reflector appear in my address as LineOne, even though the proper ...@Blacksheep address appears when I hover over it This applies to replies, and also to when I
Someone, somewhere, must have designed a soundcard, or an A/D that looks to a PC like a soundcard to allow easy integration with much of this analysis software. It really shouldn't be necessary to
What core ? What dimensions ? Does it obey the fundamental equation for saturation in a core ? Vrms = 4.44 .F . N . A . B F Hz, N turns, A core area area in m^2 B Tesla Keep B < 0.1 and ferrit
Gentlemen, Please excuse a question from one who watches from the sidelines, the amazing reports of contacts at 8.2 kHz. My question is how long does it take to measure 8270.01953125 Hz? Based o
Just a thought The say GPSDO is delivering 16.384MHz But there's a very good chance the GPSDO itself uses a DDS, so is subject to 32 bit tuning resolution. Unless it has a 48 bit device or uses a
