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Hi! Quick question, I see pins 2 and 4 in the diagram to power the VFO board and I already tried it when calibrating the mini360 5V output. My question is how do I power the 49er ? Does it feed from the VFO board ? Thanks in advance. Norbert

Afternoon to all. With everything finally completed, I fired up the first prototype of the 40m QRP Transceiver with the DDS VFO and the 49-er. Happy to report that the unit is up and running. Receive is working as it should and the rotary encoder is working as well. The radio is receiving and transmitting. Some additional testing is in the works for tonight, but for now, very pleased with the initial outcome. Great project!! Best 73s Aaron - N2HTL

Guys, I am using the sketch for the DDS VFO downloaded from QST with the encoder switch connected to Pin 21 of J1. Pressing in the encoder switch does change the increment value. However, when I rotate the encoder knob, the frequency and the increment values change simultaneously. This is the last problem I need to fix before using the Forty 9er. Any ideas? Dennis

OK guys, I managed to put everything together and so far is looking good. It powered up fine, so far I'm noticing that the encoder "step" function is not working when I push it down. It does move up and down with no problems. I can hear stations but they are very low, I hear them like far away if you know what I mean. I tried an external speaker and also with the headphones. For the enclosure I ended up using an old Netgear router that wasn't working. I stripped everything out and managed to fit the VFO board and the 49er inside. It actually looks good. For power I used an SLA 12V battery. I have not tried transmitting yet. I've been on this for a few hours now, tomorrow is another day, Good Night Everybody ! Cheers ! Norbert

Norbert, Were you able to figure out the issue you were having with receiving stations and the fact they sounded "far away?" I'm not sure how the individual parts in your 49-er kit were put into the packaging, but on mine, the cables for J2 (power in) and J4 (antenna out) were wired backwards IF you want to use a standard of the red wire being "+" and the black wire being "-". If I had made the antenna connection to J4 with the way my cables were assembled, the center conductor of the coax going to my antenna would be coming off the ground of the 49-er - which was the red wire at J4. After I fixed the issue, I experimented with switching the wires around at J4 (since I was using clip leads at the time I did the first test), and sure enough, the signals I was hearing sounded like they were being picked up by an antenna that was nothing more than a 3 foot piece of coax. I used a sharp soldering pick to push the two pins out of the white molex connector and simply reversed them. Hope you get your radio on the air and can make a few contacts with it. We should try a sched! Aaron - N2HTL -- Aaron

All: I live close to a 50KW AM station and my Forty-9er does a great job of picking it up. I have an article coming out in CQ that is a broadcast interference filter for the AM band. That article, however, is designed around a BCI filter capable of handling over 100W and uses hand-wound toroids, which is overkill for the Forty-9er. Instead, I changed the inductors to axial lead chokes and ceramic capacitors. While it is not maximized in the theoretical sense, it uses a 5 pole Chebyshev design and has less than a 0.04 insertion loss, but knocks the slats out of the AM band. The photos show the values and plot for the filter. The inductors and capacitors can all be purchased from Tayda Electronics (http://www.taydaelectronics.com/) for about a dime each. Connect it between the BNC and antenna connector on the Forty-9er. Even with shipping, it's still reasonable. You can construct it on perf board. Let's know how it works for you. 73, Jack Purdum, W8TEE

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 the Rotary library. I unplugged the Nano from the VFO board and loaded the new code. If I remember correctly, is not a good idea to load the code with the Nano mounted on the VFO board. I put it back together and Bingo the increments are working when I push the encoder, Thanks for the help. Aaron, I still hear the stations "far away". Yes, I saw your posting about the reversed wiring colors on J2 and J4 and mine also came like that. I reversed J2 with the Red + to be on the left side. For the antenna I'm using a small piece of coax from the 49er to the BNC jack, not sure if that makes a difference. I'm going to try your recommendation by reversing the antenna leads on the board. Right now the center conductor of the coax is on the left side of J4 (looking at it with the spk and key jacks being on the bottom and J2 and J4 towards the top side of the board). I have not tried TX yet. I'll keep you posted. 73s Norbert -KP4WK

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 class in our club. I wanted to ask you about the voltage adjustment of R1. I've been putting my prototype of the radio through some serious testing the past few days. My goal is to also use the DDS VFO to drive some of the older transmitters I have in my collection. But for the 49-er, I see that you indicate that J3 should be used to connect the 49-er to the DDS board at J6. If I'm understanding your instructions correctly, J3 is supposed to have a 4v peak-to-peak voltage on it via the buffer amp on the DDS board. This voltage can be adjusted with R1. As it stands now, I'm not seeing any difference in the performance of the 49-er both in receive and transmit by using either J2 or J3 on the DDS board. According to the schematic, J2 is coming directly from pin 20 on the DDS through C2, while J3 goes through the buffer amp and supplies the 4 volts voltage. I attempted to view the output voltage at J3 but saw absolutely no difference when I adjusted R1. In fact, with either J2 or J3 feeding the 49-er, I still had 5 watts output power on the radio. Can you please clarify exactly where this voltage measurement would be taken? I simply took it directly from J3 and ground but saw nothing but a few milliwatts of DC voltage regardless of the rotation of R1. Thank you and best 73s. Aaron - N2HTL

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 are progressively stronger than the fundamental. I have my 49er (Frog Sound) xcvr terminated in a 50 ohm dummy load sitting on the desk next to my K3 that is terminated in either another 50 ohm dummy load or a ground mounted vertical antenna that is roughly 30 feet or so from the K3. In both cases, the harmonics on 20 and 15 meters are stronger that the 40 meter signal, somewhat stronger on 20 meters and much stronger on 15. Has anyone else checked this? Dave, W0DF

Hi! Quick update, I hot glued a battery holder to my case and I'm getting around 12.6 volts (fully charged) with three 18650 LiOn batteries. I believe these are rated 3000mah (Samsung ICR18650-30B). The output power is 2 point something almost 3 watts according to the meter on my MFJ tuner. The battery holder came from our friends at eBay and the LiOns from a Dell Laptop battery. Also added a power switch in the back. This thing is sweet ! 73s Norbert

My 49er kit came with a red and a green ferrite core. Has anyone else had the same experience for L3 (green not black), and does the green core seem to work for L3? 73 Gary W5GW

Evening all. Some troubling news... but I want to bring it up to the group in the hopes that the same problem can be avoided for others building the radio. I've had my DDS controlled 49-er on the air now for the past week and have been making dozens of contacts with it. Fired it up this evening and called CQ a few times. Suddenly, a sharp "pop" came from the board and the D882 started smoking like crazy. Powered the radio down, and sure enough, the D882 is bulged out in a tiny area and looks quite charred. Now it's off to find a replacement... but first, a few questions. I noticed last night that the D882 was quite hot to the touch. I was thinking about putting a heat sink on it, but it was late and never got around to it. Would a heat sink be almost a requirement for that transistor - especially if the failure was caused by overheating? When I followed the instructions to adjust R1 on the DDS board to achieve a peak-to-peak voltage of 4 volts, I made the measurement using my VTVM and an RF probe. I connected the probe to J3, and the ground strap of the probe to the ground pin to the left of J3. When I first took a reading, I was getting around 2 volts... so I adjusted R1 until the VTVM was dead on 4 volts. Was adjusting for 4 volts using an RF probe incorrect? Should I have used a scope instead? I'm just wondering if I was actually overdriving the D882 because my measurement was way off. Would like to avoid this happening again for obvious reasons.... especially if we're going to be teaching a class with this project. :-) Aaron - N2HTL

I've seen some images of Forty9'rs with small heat sinks.. What is the consensus on this.. Is there enough heat generated to warrant adding one.. particularly in smaller enclosures, or should good ventilation be enough ?? What have users found that works as a good bolt on one? Steve NS3L

Some may recall or have TI Launchpads. Similar in operation to Arduino, there is an IDE that allows you to develop Arduino code into them. Here is a screenshot of the free IDE, called Energia - look and feel very similar to the Arduino IDE

I have a dilemma, I followed the instructions for setting the regulator, however the connection points called out J1, pins 2 & 4 for the 12V+ did nothing. I had the 12V ground to one of the G's. I connected the DMM to the 5V+ and G to pick up the voltage output from the regulator but got nothing. When I moved the 12V+ to one of the 12V (white pins at the far end of the header the voltage showed up and I was able to get the regulator at exactly 5V on the money.. Question... Why didn't the 12V+ work through pins 2 & 4? I checked the solder points and they are good. What would explain this and if pins 2 & 4 didn't work for setting the regulator what adverse affect will that have after I seat the modules? Steve NS3L

I finally got the DDS-VFO, Display, & Rotary encoder working..!! It appears everything loaded fine.. Just have to do some color coding of wires, only had blue ones to start.. Waiting on the multi colored ones to arrive. It work nicely. I do have a question however about the last digit on the display.. During testing of all the increments, I noticed the last digit always stays at 0.. Is there something I have wrong? Code issue? Is this a expected function? Now on to completing the 49'r kit.. Steve, NS3L

OK...rained off and on most of the day so it was a good day to work on the board. I fixed the toroids and found a few other mistakes and questionable solder joints....adjusted the VFO output to about 3 volts (with the scope this time)...got 1 1/2 watts out of it. I'll wait to get a heat sink on the transistor before I push it up to 4 volts. Found an old CPU heat sink that might work. Got to check the edge distance to see if it will squeeze onto the board. Also the sensitivity is a lot better now....I got a head cold and my ears are plugged so I can't comment on the audio level...its probably OK but hard for me to hear...did hear someone calling CQ around 7028 and a few other signals out there. Searching for a case now.... tnx for all the help don KC1AT

Nice article in the new issue of QRP Quarterly, Jack. Where do we slip that code into the 49er project code to take advantage of the quick QSY feature. Dave, W0DF

OK so my 49'er is deaf...worse than me (double hearing aids)...takes about 1 millivolt out of my Wavetek SG to hear anything worth listening to.....(like a Hallicrafters S-120 with low line voltage.) Output is low too...maybe a 1/2 watt or so... I think I mis- wound the torrids...so L3 is 11 turns (per the instructions) ...so do you count 12 passes thru the center ???? ( the first turn is really 2 passes thru the core??? right ???) same for L4..how many passes are thru the core ??? ,...16 or 17 ???..I did double check the caps...those are all correct. Yeah and I smoked the final when I was tuning it up too (after a while key down)...got my stash of finals from China the other day...these things aren't like 6146's are they ??? hahahaha ..been following the heat sink thread...I'm trying to make some sort of heat sink for it.... any help appreciated for an old tube guy struggling to get into the 20th century... Don KC1AT ps...the arduino part/ VFO works flawlessly ...hahahaha..love this project.

We had one member who thinks that his kit contained faulty/mis-labeled parts. If anyone else feels this way, please let me know the name of the supplier and I'll start a list of "questionable" suppliers and post it here. Jack, W8TEE