New TCXO signal generator at The Palm HQ

Here's a project I've been meaning to tackle for years.  Long ago I bought some 14.4 MHz temperature-compensated crystal oscillators (TCXOs) from "pyrojoe" on EBay.  I just finished boxing one up as a signal generator for VHF-UHF-SHF receiver check-out.

I used a circuit from Paul Wade, W1GHZ that he published in the August 2010 issue of QST.  The circuit's there in Figure 4, hat tip to Paul.

Paul has a 64 MHz oscillator in his and states, reasonably enough, that that's a good starting frequency because, "The harmonics should be audible at 2304, 3456, 5760, and 10,368 MHz, but there are no harmonics at the common IF frequencies of 144 or 432 MHz, reducing the chances of detecting a birdie".  Fair enough, but I'm actually happy to have a signal at 144 and 432 also -- I should be able to switch things on and off to detect if it's my signal or a birdie.

I substituted a MAR6 for the MAR3 in the schematic but the principle is the same -- over drive a MMIC with an oscillator to generate a bunch of harmonics.  Instead of Paul's 9V battery regulated down to 5 VDC, I'm running mine from a 3.6 V Li-ion battery and boosting to 5 VDC for the oscillator.

And it works great!  Check out the full scale signal on my VX-6R at 576 MHz, the 40th harmonic.  It's easily audible at 1296 MHz as well.  I am very curious to see just how close this dude is in frequency when multiplied up many times.  Now I just need to build my transverters for 2304, 3456, 5670, and 10,368 MHz....