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How many people have spectrum analyzers or access to one? I have read about spurs created by chips like the AD9850. How does a typical ham checkout one of these devices? Back in the OLD DAYS (1960's)

John, Still in development... ken

... doesn't work doing things in a hurry, Make that 82pF for the fixed. That would put the 50pF trimmer somewhere near mid-range. ----------------------------------------------- You'd want it to be 10

You'd want it to be 10 MHz.. 25t on a T37-2 is about 2.5 uH That would be close to resonance with 100pF Use a fixed capacitor of 47pF in parallel with the 50 pF trimmer A pair of them hooked up back

Doug did a great job on that project. How would you modify Doug's transformer for 10.7 MHz? Alan, N8WQ

Doug Hendricks replacement for the 42if123 transformer /g/qrp-tech/files/KI6DS/42IF123Daugtercardarticle.pdf dave /nt1u

Hey... what gives? Is this for real? George was my Auntie not my mother! How am I supposed to answer a question when the question is wrong? :-) Thanks for making this resource available! -- 72 es

Any idea of when the FT8 transceiver kit mentioned in CQ Magazine (Aug) will be available? John AE5X

Gang, QRPGuys is open for orders after this year's Summer shutdown. We have added a product that may be of special interest to SWL listeners and some hams. It is an active antenna splitter that will

...is it useful? The graticule, although small, still provides useful information about viewed signals.* An approximate measure of DC and AC voltages using the graticule And and approximate measure of

It's not difficult to do a band-pass filter to do the job. Using Elsie: Emacs! 50/50 rounded values Marker: Frequency: Trans: Return: VSWR: Zin: Real: 10M -0.89 -54 dB 1.0038 50.2 50.2 -3dB points

I have a limited supply of the 10.7mhz xfmrs. I can spare two for $10.00 Shipped. The boards for the Neophyte can be obtained from FAR circuits. Regards. Ollie k0lqk

Forgive me, The basic radio is the Neophyte... its considered a basic builders design. Winding a toroid transformer, or simple solenoid coil for 10mhz is not hard. Finding a 10.7mhz can might scarce,

Hi I have tried to do MSK144 with the Si5351A and it does not work in the FMD. The Si5351A is not fast enough. However, I have not tried using both synthesizers and switch between them. I will give it

To use a 5351 for RTTY (FSK) you can use two of the PLLS set for the desired MARK and SPACE frequencies and use gateing with the UART Tx signal. That comes close to how it was done in the OLD DAYS

A low spur and fastest frequency change device is the DDS family 995x from Analog Devices. You can have multiple preset frequencies, phases, and built in auto sweep, all that can be triggered with

Speaking of RTTY, I've done both RTTY and CW on an AD9851. Not on the air but just as another trick in a little project using one as a test signal source. The Elecraft XG3 signal generator also has

That's normal for a PLL. DDS is the way to go for fast frequency changes, like you need for fast frequency sweeps or spread spectrum modes; they can change frequency in microseconds.

The Si5351 can be reprogrammed on the fly but it does not change frequency very fast. I tried to do a frequency sweep and found 3.5 milliseconds to change which severely constrained the number of

Finding the input transformer could be hard...Hal/WB4AEG ---- On Tue, 06 Aug 2019 21:53:55 -0400 ajparent1/kb1gmx <kb1gmx@...> wrote ---- kd1jv has a simpler to build radio and work well. It has