วันพฤหัสบดีที่ 10 ตุลาคม พ.ศ. 2556

3 axis CNC for milling PCB - Part 2

From the draft of CNC machine. I cutting and drilling  the woods. Assembly all cut wood for checking dimension and area of Plan working. It's reduce to 140 x 190 mm. Next jobs find the milling motor and assemble the Axis motors.

วันอังคารที่ 20 สิงหาคม พ.ศ. 2556

3 axis CNC for milling PCB - Part 1


Draft the Rubber Woods for making CNC Machine. This will be using 14 parts for assemble. Rubber woods found in local store. This design can working area in 200x250 mm. Enough for milling PCB.
Now! We will order the woods. Estimate cost for woods is ฿800.

วันจันทร์ที่ 15 กรกฎาคม พ.ศ. 2556

SDR received JT65 on 20m

Sunday I test my homebrew SDR. I get information from YU2LM's Website. Select design single LO Frequency at 140625 kHz generate from Crystal Oscillator. JT65 operating in 140760kHz. This is on range of my SDR. While operate with long wire antenna. I received first QSO between BV7RJ and JA1PLT and signal at -24db. So I think very weak but it good for experiment. It first time.

วันเสาร์ที่ 18 พฤษภาคม พ.ศ. 2556

DDS with AD9850 and Basic Stamp microcontroller..(part 1)


I and my friend in group "Thailand Amateur Radio Group" will dicuss at RAST meeting in May. We talk about make DDS project. After we buy a DDS AD9850 module. We go back to a workbeanch for starting our jobs. Somebody used RasberryPi foe control, somebody use adurino and I select Basic Stamp. This for start to re-learning a basic language again (I lean at grade 1 in High school). So shall be lean step by step.
The Basic Stamp 2p24 has feature for I2C communicate to module ,16 I/O ports for connect Encoder, Buzzer etc. and include feature for LCD command.
Now I can write a program for up and down a data and output to screen. Next step make a program for control DDS.

วันเสาร์ที่ 20 เมษายน พ.ศ. 2556

New 20m Invert V Antenna test in 5Watts WSPR

Last week I made my antenna for 14 Mhz band. I gone to Japan in March and brought the Balun BU-50 back to Thailand. When I were making antenna by cut a wire 1 mm dia and ½ wavelength.

Propose for this antenna for using in portable station. I test in WSPR mode at 5 watts because I’m busy, I can’t monitors in 24 hrs. After open the wspr.org to check a result.

My station and new antenna can spots over 700 station. That is good result for new antenna. Next I will try in portable station and other mode.

 

วันพฤหัสบดีที่ 28 มีนาคม พ.ศ. 2556

Today QSO result ; 6 QSOs on 20m JT65

14:01  1  -15 -0.3 -22  K E22ICQ JH3IMR -10 
14:28  4  -9 -0.5 794  B E22ICQ RA9JK -12 
14:36  4  -17 0.9 571 B E22ICQ JA1BZJ -08
14:42  1  -15 0.7 544 B E22ICQ JH1QKG -17
15:07  3  -8 -0.8 388 B E22ICQ 9V1LX -09
15:24  2  -3 -0.7 388 B E22ICQ RA0CHK -09

TNX for QSO.
Now operating WSPR. 73

วันเสาร์ที่ 9 กุมภาพันธ์ พ.ศ. 2556

Weekend Project ; Peaberry SDR by AE9RB

Dec 2012, I order a electronic kits from internet. The kits is Software Define Radio and design by Mr.David Turnbull (AE9RB). I got its from a post box in Jan 2, 2013. Then I checked all parts in package and learn instruction in http://makeprojects.com/



After I received a kits from I order in ae9rb.com I saw a good packaged for protect a mistake parts. SMD parts are difficult to check in parts if you have a instruments at you workbench. My order is a set for my first do its yourself.




First step follow as http://makeprojects.com/ print a table for select the bands. I selected 80/30/40 meter bands. A fig show I mark portion of value for those parts.



Then I prepare a inductor and transforme (L1-L7, T1-T5). and next solder an 0.1uF capacitors on PCB.



Warning ; SMD parts easy to broken. Carefully a assembly.

After assemble 0.1uF capacitor should be checking an parts don't fail.



Add D1 , R1, C1, C2, C3, C4 and Socket J2. Be careful a pin of capacitor and pan have small area to solder.



next solder U1 and U2. Instruction inform parts name "NX1117CExxZ". I saw on package indecate "W257CExxZ". Check in datasheet is corrected.




Supply 12-15V for check both regulator. I supply 13V and voltage output are 5.0 and 3.3 V.



Soldering J3, R14, R15, R16, C21, Q3 and check voltage at collector should be 2.0-2.5V. I measure 2.2V. Then soldering U3, U4, R2, R3, R12, R13, R4, R5, J4, J5, J6



This portion carefully a solder. U10, U11 and P1 are small pitch and small pad. My technique add a little Lead-fee on pad before solder an SMD parts. A flux is helpful for easy soldering.



Follow the instruction for assembly parts then a step 20. I can connect to computer by USB and supply a power. The computer should be detect Peaberry SDR. I install driver for download from AE9RB.com and receiver can operate.





Setting on HDSDR. A peaberry SDR should be show in sound card selection.



Step 24 ; Don't forget a mark on transformer T4, T5. May be made misstake assembly.



Final parts Q6, Q7, Q8 after bend I tick a screw and nut before soldering. Just not finish, must be make external LPF.



Weekend job and now a midnight in Thailand. Must be going to sleep.

Thailand field day contest a alone contest for Thailand

Last weekend in Thailand a ham radio enjoy a alone of contesting in Thailand. Thailand field day. Contest is sponsor by 100watts Magazine. I gone contesting at my home. In condition QRP home station (Transmit lower 5 watts) . In 24 hours i made 36 QSOs as below.

Band      Mode.           QSOs
2m.        FM voice.      29
2m.        SSTV.            6
2m.        CW.               1

Good experiment last weekend QRPer.



วันพุธที่ 2 มกราคม พ.ศ. 2556

Homebrew Long wire antenna



A new Homebrew Long wire antenna. For big holiday in happy new year 2013. I made a antenna replacement old dipole antenna 10 meter band. This antenna I use 1.5mm dia  wire around 15 meter long. The wire connect to balun 9:1. I made this balun for longwire antenna.


This is homemade Balun 9:1.  I measure by spectrum analyzer, It's Cover 1.8-20 band. I will be test on the air