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OK, thanks Jack.? As I said, my testing methods were primitive and just a first glance.? I'll dig into the details next week when I get back to the workbench.? I may have something messed up on the

Dave: Dennis has posted the spectrum traces for the VFO and they all look within specs to me. Jack, W8TEE

Yes... And Dave, If you haven't done so yet, you may have to run the formula that Jack describes in the QST article in order to get the VFO calibrated perfectly. We breadboarded this project every

Don't forget that the crystal on the DDS board may not be exact and you should expect some deviation. The article details how to correct for the "slop" you may find. 73,Jack, W8TEE To:

Thanks for the response Aaron.? I haven't had time to investigate what is happening yet and won't get a chance to do that until next week sometime as I'm getting ready for a short trip.? My DDS is

Hi Dave. I have to admit that I haven't but I certainly will now. When I fired up the DDS controlled 49-er for the first time, I checked it against my frequency counter to see what it was doing. I was

Has anyone looked at the harmonics on their 49er. I must admit that my testing method is primitive but looking at the 2nd and third harmonics on my K3/P3 panadapter, the 2nd and 3rd harmonics on mine

Good to hear! That was one of the design goals that the three of us shot for when we started the project. As I mentioned in the article, we wanted a VFO that would be capable of powering older rigs,

Thanks for the reply, Jack. I successfully made the adjustment to 4 vDC using an RF probe and my VTVM. And Farrukh is absolutely correct... you need to give R1 quite a few turns in order to see any

Got this today: Hi Jack, There are two pots on the DDS VFO board. R1 adjusts the GAIN of the RF buffer amplifier and hence the AMPLITUDE of the sine wave output on J3. R8 is for calibration of

Thanks for the relay, Jack. And therein lies the rub. Rotating R1 has no effect whatsoever on the output... but I'm not thoroughly convinced that I tested the output voltage at the right spot on the

Another possibility that I think I remember me doing was putting an electrolytic in backwards and that cut the audio in the next stage. We I heard that, I said: "No way...I'm too careful." Way. I had

Aaron: Once again, I'm the software guy, not the one who designed the board; that was done by Farrukh and he is better able to answer these types of questions. That said, I do know that the pots can

Jack, and all... As you know, I'm in the process of putting together a very detailed construction manual for the radio which will be handed out to everyone who takes on the project as part of the

Norbert, One test I did make was to disconnect the speaker, plug in the headphones, and pull the DDS board and check for hiss. It was still there. The I pulled the oscillator chip - U2 (LM 602) and

You've been writing about this for over a week. Have you tried what has been suggested (i.e., replacing the LM386, checking the transistors, etc.)? Have you tried different sets of headphones rather

Hi! I played with the radio for a while yesterday and I'm having some difficulty copying other stations. I hear them very low, like "far away" , fainting. I'm noticing a lot of the "hiss" noise that

Thanks for the quick reply Jack. Guess I must have missed that file.? I think I have enough parts in the junk box to put one together.? I'll let you know the results.Dave, W0DF

There are photos of a BCI filter that should work with the Forty-9er posted on this site along with the values. It will be less expensive to make, since the CQ article is for 100W and uses hand-wound

Hola! Dennis and Jack, I was able to fix the "increments" issue with the new code from Jack. I ended up using the file named TempVFOCode.ino and I replaced the rotary.h and rotary.cpp (lower case) in