Tuesday, 28 April 2015

DIY LF oscilloscope

One of the most interesting Do It Yourself kits I saw recently is digital oscilloscope with a 2.4 inch color TFT display. The scope can show signals up to a frequency of around 200 kHz.
The price is amazing: 21 euroos...

All the ins and outs can be found via this link.


Another interesting gadget to identify your unspecified components:


Saturday, 18 April 2015

Holy Land contest

Today I made some QSO's with Israelian stations participating in the Holy Land Contest 2015.
Conditions on 10 meter were ok since in 20 minutes I worked following stations:
4Z67TL, 4Z5LA, 4Z5WC, 4X4JU and 4Z1UF.
I used 20 Watts in USB around 28.500 MHz


Friday, 17 April 2015

More Moore

Today I ran into an interesting visualization of Moores Law;
the amount of integrated transistors versus time.
Each 2 years the amount of transistors doubles. From the 4 bit 4004 processor from 1972 to the most sophisticated processor nowadays (Xeon, 15 core). 
50 years ago Gordon Moore was right:

This week I drove along an old railway station that is not used anymore as station. I could not resist making a nice picture.

Station Vogelenzang-Bennebroek - along railway line Leiden CS-Haarlem - was built in 1880 and used as railwaystation until 1944. 

Thursday, 9 April 2015

BC-696 transmitter

This week, at the radio club, a green radio, BC-696 was shown. This transmitter has been revised by Mans, PA2HGJ. He designed a Power Supply Unit for the valve transmitter so now it can be fed with 230 VAC mains.
The BC-696 had been used in Worldwar II in bomber aircraft like the B-17.
The transmitter originally uses 28 VDC power and was operated in CW or AM voice mode. It has two 1625 tubes in the Power Amplifier and is capable of delivering 50 Watts RF in the 80 m band ( unit operates from 3 - 4 MHz).

                               Frontview BC-696 CW/AM transmitter 

                                                Top view opened BC-696

Bottom view 

Side view

PSU, designed by PA2HGJ