vrijdag 5 mei 2017

X-Phase II Noise Canceler part 2.

A few years ago, started the build of the X-phase II noise canceler, but never completed it. Now I found the time to do this. I ordered the missing parts and put them on the board. Nothing special, only the winding of the toroid was the most interesting part of the build. I used the FT50-43 toroid wich covered between 1,5Mhz and 50Mhz. Because the original manual is in German by DG0KW, I had to figure out how to wind the toroid. First you take a peace of 58 cm, 0,2mm wire. Twist it together with a 13cm, 02mm wire. Put 1 winding through the toroid. Then 3 windings to the left and three windings to the right side of the toroid. Now there are 7 twisted windings on the toroid. Now you are half way. Then, you put 6 windings on top of the three twisted windings on the left side with the single wire that came lose from the twisted wire. Then you put another 7 windings near the 6 windings. So in total 13 windings. You do the same on the right side of the core.

After I completed the build, it was time to power it up. The LED became green and I heard the relais energized. And, there was no smoke coming out of any of the parts :). Only thing to do is to connect the antenna plugs and test the circuit. 


dinsdag 10 januari 2017

New in the Shack "Yaesu FT-225RD"

Recently I was lucky enough to get my hands on a Yaesu FT-225RD 2-meter all mode set. This rig is in mint condition and I even have the original manual and purchase receipt of the original owner who bought it in the year 1980. Purchase price in these day`s was 2150 guilders, which is now approx. 2150,- Euro`s.

I allready made some QSO`s with it and I got nice feedback about the audio quality. So far I could not found any issues with this rig. Some specs I got about http://www.rigpix.com/

zaterdag 2 april 2016

My First Bitx20: Just two pictures.

After testing my Bitx20 Exciter, I soldered the front paneel to the exciter board. Actualy nothing much to tell, so just two new pictures. Maybe, maybe, I don`t put a linear amplifier on this Bitx, and use it for Whisper because the VFO is so stable!

maandag 28 maart 2016

My first Bitx20: Bitx20, one step further!

Yesteday was Easter holiday, so I decided to build on my project again. I have cut two pieces of PCB to create the front and the back of the project. In the front there is room for a signal meter, mic. jack, on/off switch, volume potmeter and the Si5351 VFO. On the back I drilled a hole for the antenna connector, and a hole to put the 12V dc power cable thru. Just like all my HF-projects I used a SO259 female socket for the antenna connector. I made the connections from the SO259 and the input of the Bitx20 using RG174 coaxial cable. Keep in mind that I didn`t build the bandfilter yet, so the RG174 is connected to the 3th bi-directionel amplifier of the rig. When I was connecting the Si5351 VFO to the Bitx, I ran into a small...minor...actualy no problem. The VFO uses 5Vdc, and the Bitx20 uses 12Vdc. So, I looked in my box of desolderd used components and found a 7805. I soldered it on the +12v rail, ground and connected the 5V output to the VFO. You can see the 7805 on the PCB in front of the SO259 antenna connector. So, the VFO has power and the VFO-output signal was connected to the Bitx20 HF-mixer, (you know? the one with only one transformer!) by using the same RG174 coax cable. Time to test the rig. As soon as I turned it on, I heard a lot of activity. There was a contest on the band, so I could test the Bitx20 very well. It was very interesting to  hear all kinds of QSO`s on the 20meter band, but also the beeps on 10.000MHz (my IF on this project) and some radio broadcast stations because the bandfilter is not there. The VFO runs from 4.000MHz till 4.350MHz. You can add this signal to the IF of 10.000MHz. So I can receive all activity between 14.000MHz and 14.350MHz. But, ....there`s always a but. The VFO signal is not only added to the IF frequency. It is also extracted from the IF frequency. So, I also receive activity on (VFO 4.000MHz~4.350MHz) - IF 10.000MHz = 6.000MHz~5.650MHz. Now you know why I receive not only amateurs on 20 meter, but also some other signals and harmonics because the bandfilter is missing. Hopefully my parts for the bandfilter arrive soon.

vrijdag 25 maart 2016

My first Bitx20: My first "Dead Bug" Bitx20

Remember my first ever build Bitx20? I never completed the build because I didn`t have enough knowledge about building a SSB transceiver. Now, a few years later, I decided to grab the only half completed Bitx and give it another try. Because I have build quite a lot of Bitx projects, my first project was not complete anymore. In the years, I borrowed some components for my other projects from this first build PCB. This is actualy the first design of the Bitx20. You can see that the mixer section where the VFO frequency comes together with the IF-frequency, consists of only one transformer. In all my other builds, I used two transformers.

In this project I used the BF199 HF transistors instead of the 2N3904. On top of the board you see the power lines bar for +12V,cont. + 12Vsend  and +12 V Receive. As you can see, the bandfilter is missing. 

Picture of the soon to be front panel and back-panel. An old VU-meter for signal level and the very good Si-5351 VFO from SDR-kits. So still some work to do, but after 6 months of doing nothing with the hobby, it`s time to get the soldersmoke in the shack!

 Bitx 20 before I ripped it apart.

zaterdag 25 juli 2015

New Si5351 VFO by SDR-Kits

A few weeks ago Ton (PA0KLT) asked me to test a new developed VFO by SDR-kits based on the Si5351. This little VFO (34mm by 25mm) consists of the Si5351 ,which is a programmable I2C-Cmos clock generator programmable at any frequency + VCXO support.Also on the board a ATtiny85 ,8 bit microcontroller that runs on 16MHz~20MHz.At the back of the PCB you will find the Rotary Encoder to adjust the frequency.This VFO is a very clever design because the only thing you have to do is drill a 7mm hole in the front of your case and attach the VFO with the mounting ring of the Rotary encoder.The VFO works on 5 Volts and it uses 18 to 24mA.This VFO is programmed in the range of 4.000MHz ~ 4.350MHz for the test with the Bitx20 that has a IF of 10.000MHz.Any other frequency can be programmed for any band or IF.

When you power up the VFO the start frequency is 14.200 MHz USB.The dial speed of the VFO is 1042Hz X 96 = 100KHz each turn.If you press the Rotary Encoder shortly ,the VFO goes to fine tunning mode.Now we have 26Hz X 96 = 250Hz each turn.When we press the Rotary Encoder for a few seconds,we return to the offset frequency of 14.200MHz again.

I connected the new Si5351 VFO to my Bitx20 "Dead Bug Style".Before that I had to disconnect the onboard VFO and instead of that I put the output of the new VFO directly on the mixer side of the Bitx20.I also connected a frequency counter for the test.When I turned the power on ,the rig immediately came to life.Several stations where heard and the VFO performes great. Because there are no inductive parts on the VFO,there is no "hand effect"when you turn the dial of the Rotary encoder.When you choose a frequency,it stay`s on it,even after a 3 hour test period the frequency didn`t shift.I also made some QSO`s with the set-up.There was no re-tune needed after I let go of the microphone ,which is needed with the on-board VFO.

Picture of the set-up.The Bitx20,IK3OIL frequency counter and the Si5351 VFO.Picture below the scematic of the VFO.

woensdag 13 mei 2015

Multiband Bitx: First reception test

This is the first video I shot of the reception from my Multiband Bitx.First you hear a Dutch QSO on 40 meters in LSB.After that I switch to the 20 meter band where a station is calling for CQ.Because this is the first test,there are a lot of adjustments I have to make.USB/LSB finetunning,AGC and S-meter.Also the frequency reading of the VFO is not correct yet.On the left side of the Bitx,you see the Amplifier and Lowpass filter PCB.I started the build of that as well en began to put the parts on it.