I build this just because i wanted a quick and easy project to kill some time. I found the schematics online (PH2LB and Here). All the necessary parts i had laying around. In the end it looked like this: It give a fair a mound of “Noise” according to my scope. I have put it in a little enclosure, also i tried it on my frequency counter. It seams to resonate around the 1.7 […]
This weekend I reorganized the shelf to fit my measurement tools.
In the januari 2017 number of Razzies there was an article about a lightning receiver. They started with an basic receiver, but later changed to a pre-build module with more capabilities. My interest wen’t to the basic receiver, simply because, like many of my little projects, its all made up around component that many of us have laying around. So I build the little receiver, only to discover i ran out of standard coils of 1mH […]
Today i received a nice little package. Inside was a Pi-Hat for LoRa. Specifications Lora Spec 168 dB maximum link budget. +20 dBm – 100 mW constant RF output vs. +14 dBm high efficiency PA. Programmable bit rate up to 300 kbps. High sensitivity: down to -148 dBm. Bullet-proof front end: IIP3 = -12.5 dBm. Excellent blocking immunity. Low RX current of 10.3 mA, 200 nA register retention. Fully […]
The idea I have some old server power supplies laying around with the intention to convert them in to a good power source for my HAM stuff. The base will be and DSP-600 from HP, capable of producing 47Amps on 12v. With some tweaking it can produce 13.8V, Also it has a 5V. Always handy for testing purposes. What is needed So here are the basic ingredients: […]
I have had the parts laying around for a while and with the arrival of the 2U high 19 inch chassis it was time to put it all together. A 12V (13,4 actually) power supply for in my rack. Some specs: DV voltage : 13,4 Volts ( i can’t up the voltage more on the 12v supply) DC Current: 12,5 Amps ( all tho it will be fused at 10 Amps.) AC voltage : 230V […]
In september hebben we weer een water weekend gehad, we hebben wat mooie foto’s gemaakt van de 3 boten op het water. Deze wilde ik toch ff delen.
Sinds I have a SEM-35 I have noticed that the mic really sucks (excuse me for the langue). But these carbon microphones have a tendency to become clothed. It come with age and moisture. So after searching the web i found a side that has nice description how to convert it to a electret microphone. The site is in dutch, so i’ll try to translate some passages. The site and source of this info in dutch can be […]
This year during the 40th JOTA at my Scouts Club we wanted to do something new and different. As this will be the 40th time PA0AKS/J will be active, and the last time under his super vision. So we are building an ATV station. Here are some specs: RX : 10.3Ghz Hardware: Philips Satellite reciever, LNB with an 9Ghz L.O. (resulting in an 23cm rx at the output). TX: 13c, (2330Mhz) Hardware: Gigawave 10Watt TX, […]
At my birthday party someone showed up with a awesome old radio. An old SEM-35 manpack radio. SEM-35 Specifications Frequency Coverage 26 to 69.95MHz Channels 880 spaced 50kHz Modulation F3 (FM) Deviation 15kHz max. Transmitter RF Output 150 mW or 1Watt Frequency Stability < + 3.5kHz from -40 to +600C Receiver Sensitivity < 0.5 micro volts for 10db reduction in S/N Receiver Selectivity > 80db at + 50kHz AF bandwidth 400 to 3000Hz Receiver AF […]