This is rather a reminder, not a real post. This is a collection of links to help me in my quest to control this device.
KiCad Templates for Orange Pi Zero
KiCad templates for two different hat models for Orange Pi Zero boards can be downloaded from my GitHub repo. Two different KiCad templates can be downloaded in the same GitHub archive: one uncut, 46×48 mm exactly same size as Orange Pi Zero; the other one has some cuts for network and USB connector, to accomodate […]
Kenwood THD74 measurements
Some RF power masurements done with my Rigol DS 815TG of my Kenwood THD74.
AD8307 RF Power Meter III — build
This will be another short post. I also made the GitHub repo public, but please be aware, current design is flawed. If you use it, you acknowledge that you use it on your own risk. Today I managed to build the revision 1.0 of this power sensor, not without some lessons learned. It was my […]
Kenwood TH-D74
We first met — I think — in the summer of 2015 during the Hamfest in Friedrichshafen. At that time I had a mobile Kenwood transceiver TM-D710 which was quite nice by its own. However, after several months using the TM-D710 I got increasingly annoyed by some of its shortcomings, most of them purely subjective (but I […]
Beacon with SiLabs module
This is a beacon project started by my friend YO5VAE. He faced some issues while programming of the Si4463-based module and I thought I might give a hand. I resoldered the entire project on an empty Arduino shield to allow expansion of the project with some additional modules. Below are some pics, but probably the […]
Boards for prototypes
For low frequency projects, a fast way to prototype is using a bare PCB and scratch some dividers that allow “manhattan” style prototyping. I am especially very fond of this prototyping technique and I believe that PCB design should be avoided in the early stages of prototyping. Jim Williams was an artist in such designs. […]
OCXO tests
A couple of months passed since I purchased two 10 MHz OCXO modules from eBay. And, to my shame, I didn’t even tried these. Yesterday I did a quick test and the devices are spot on. Both measured on my TTi TF930 3GHz frequency counter: The OCXO needs apx 10 minutes for proper warm up […]
Electronics from China — Pixie CW
Power supply: DC 9v – 12v Antenna: 50 ohms, is not balanced, 7MHZ band, standing wave ratio below 1.8 Receive the static current: 10 mA @ 9 v Transmission power: 0.8W @ 9 v, 1.2W @ 12 v Frequency range: 7.023 MHz launch, receive 7.023-7.026 MHz (7.023 MHz crystals) Stray (harmonic) inhibition: – 20 db […]
Electronics from China
I am pretty pleased by the outcome of my commercial endeavours on eBay. Purchasing seems to be a pleasure; until now — with just one exception — I was spared from any nasty experiences. After several small items that I ordered in part for my curiosity to evaluate speed and quality of shipments from chinese suppliers, I […]
144.8 Mhz TX for APRS (3)
This is a quick update post. The road I took with this little project is slowly getting to a dead end due to what it seems to be a lack of available crystals for 144.8 (like 48.26 or 28.96 MHz, for using the third or fifth harmonic). I believe that, currently, all APRS modules are […]
144.8 Mhz TX for APRS (2)
More work today and yesterday on this project. Still locking on 144 MHz, but this is normal, the crystal I used is a 48 MHz overtoned, working on the third harmonic in this case, thus spot on 144.0 MHz: I managed to clean the output, at the expense of transmitted power. I used a 7-pole 2m bandpass […]
144.8 Mhz TX for APRS
Been busy at work lately, but still had some time for myself. Latest idea: a low-cost APRS beacon, done with a classical 144.8 Mhz TX and a μController. AX.25 on air. Automatically. So these days I’ve been busy making this: Winding coils, soldering, measuring. Fun. The frequency is remarkable stable, given the rudimentary nature of this. For example, […]
The Indestructible LDMOS
Mailbag today 2 ! This time from NXP. OMFG, look what I got ! This baby will definitely end up in a power RF amplifier for my Ham Radio fun time. This will be a project. THANK YOU NXP ! Got them both today ! And I have to tell you, the girls and guys […]