KT-8900 VHF/UHF transceiver

If you are looking for a small, low budget, VHF/UHF transceiver the KT-8900 from manufacturer QYT from China might be your choice.
For under $100 you are the owner of this FM mobile transceiver with a weight of only 400 grams.
It has a frequency range for VHF from 136 to 174MHz and for UHF from 400 to 480MHz.
Transmitter output power is 25W in the VHF range and 20W for UHF operation.

http://www.ebay.com/itm/QYT-KT-8900-Mobile-Radio-Double-Transceiver-For-Car-VHF-UHF-136-174-400-480MHz-/252081794687?hash=item3ab13eee7f:g:d4kAAOSwHnFV6vEk

A picture of my view at the new QRL at Schiphol

Encounter with Aeronautical Mobile station

Yesterdag, August 5, I made a nice radio contact via the repeater PI3UTR (145.575 MHz). With my UV-5R porto I had a QSO with Gerrit, PA0GJC/AM, who was transmitting from a small piston engine driven aircraft. At the moment of our contact he flew above the Dutch coast near Noordwijk heading for Rotterdam-The Hague airport.
I hope Gerrit acknowledges the radio contact by eQSL.

DIY frequency counter

There is no excuse anymore not to provide your receiver or transmitter with a frequency counter.
For 6 euro's I built a counter which measures frequencies from 1 Hz till 50 MHz.
I ordered the "Do It Yourself" kit here:

http://www.banggood.com/buy/Sku184055.html

The counter can also be used as crystal tester.

The counter is designed around a PIC 16F628 that also contains a table with most used IF frequencies which you can add or substract from the measured frequency.

Very nice design with big LED displays !

Kit parts

Half way

                                 The counter works ! 16 MHz X-tal here under test

Close look with 4 MHz X-tal under test

Off topic:

Harvest near  'Stad aan 't Haringvliet'

Collector items

Yesterday I found a box with old components. Some of them were germanium transistors.
I must have kept those semiconductors since about 1977. I remember building a simple MG-radio receiver with an AC125. 
I am not good at throwing away things. Now these components have become real collector items.

http://www.ebay.com/itm/OC140-Transistor-Vintage-Philips-Stock-/231620456594?pt=LH_DefaultDomain_3&hash=item35eda7b092

V1=AF121, V2,3=AC125

60 m band

As a result of a request from VERON ("Vereniging voor Experimenteel Radio Onderzoek Nederland") to "Agentschap Telecom", in the Netherlands there is a chance that part of the 60 m band (5250 - 5450 kHz) comes available for experiments in the near future. This band, located between 40 and 80 m, is very interesting to do (QRP) experiments.
Although the operating frequency is below 10 MHz, the common voice mode used in the 5 MHz band is USB.

In advance of the release of the bandsegment I thought about a 5 MHz transverter. When using a 21 MHz transceiver, with a 16 MHz local oscillator, a transverter could look similar to the design shown below.

70 cm WebSDR

Since begin this month a UHF 70cm WebSDR has been activated.
The 70 cm antenna of the Software Defined Radio has been located in the
centre of the Netherlands, the Gerbrandytoren.
The frequency range of the receiver is 430.000 - 432.000 MHz
The URL to access the receiver via the internet is:

http://websdr.pi1utr.ampr.org:8901/

Source:
http://www.hamnieuws.nl/70cm-websdr-voor-nederlandse-repeaters/#more-6502

Hybrid TV PCI Card

If you want to watch life TV on your PC you might install a DVB-T USB stick these days.
A couple of years ago, when those USB sticks were not available, there were computercards that did the job.
Last week at kingsday we went to a fleemarket and found an unused Hybrid TV tuner card from Zolid (manufacture date 2009).
In the box, apart from card and software, an antenna, remote control and IR-eye had been included.
This morning I installed the card in an old Pentium IV pc that runs with Windows XP.
After installation of hard- and software (driver and "Total Media") I now can watch "free-to-air" transmissions of DVB-T stations (NPO1, NPO2, NPO2 and a local station) and listen to some radiostations. Decoding of "Teletext" signals works fine.
Besides the reception of DVB-T transmissions there is an option to watch analogue signals. Although the max receive frequency is 864 MHz, this option might be interesting for further experiments. 

Components used on the TV card:
-TDA18271 (tuner)
-TDA10048 (demodulator)
-TDA8290 (analog IF demodulator)
-SAA7131E (A/V decoder/pci interface)


http://www.datasheetarchive.com/dl/Datasheet-082/DASF0045845.pdf

                                                  Zolid TV card

Zolid TV tuner card

                                                      TV card installed in PC (aft card)

                                                   "Total Media"  up and running

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.

http://www.banggood.com/DIY-Digital-Oscilloscope-Kit-Electronic-Learning-Kit-p-969762.html

Another interesting gadget to identify your unspecified components:

http://www.ebay.com/itm/121309248191?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

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

http://www.iarc.org/iarc/#HolylandContest

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.