Techie bits, the back to front bit...

I'm sat here with a pile of bits and a spaghetti mess of wires which is the partially developed radio interface.

This mess, above, is a working USB-CI-V, PTT and sound card interface.

Which connects to:

The audio isolator and PTT Isolator board
All connected to this, my IC-718.

So the big question, does it work?
I'd say that's a yes.
Heard 5051 kilometres away !

Colour me impressed but that's with 5 Watts into a random length of wire, roughly 15 metres in length and tuned by the AT-130.




Comments

Post a Comment

Popular posts from this blog

MiniPA 70 build, almost there.

Image
A quick update, I needed a heatsink so I found one from an old PC which is more than adequate, weighing in at almost 650 grammes I reckon it should be able to handle the heat. Problem though, it's not flat. Which makes it kind of difficult to mount the board. Now, I could use some standoffs, PCB pillars cut to length but I'm a little light on machine tools to make an accurate job of it and it'd annoy me that it was 'wobbly'. As it happens, I recently bought myself a new toy. A Flashforge 3D printer so this seemed an ideal opportunity to learn to use a CAD program and find out how dimensionally accurate the printer is. It turns out, it's pretty good. And the PLA takes a thread really nicely. So, my Mini PA board now has mounts, I just need to drill and tap some holes in the heatsink.
Read more

Replacing the Teensy 3.2 with 4.0 in the GQRP SCD Sudden Digital VFO

Image
 Place holder for GQRP SCD Digital VFO Post   The chip shortage has struck down the Teensy 3.2 which was used in the GQRP Digital VFO here: https://www.gqrp.com/suddenvfo.htm   Obviously that's a problem.  However, there is light at the end of the tunnel, the Teensy 4.0 is pin compatible so could be a drop in replacement.   I downloaded the 'sketch' and tried to compile it, which failed with what looked like potentially simple to resolve errors and a *lot* of warnings about unused and uninitialised variables. The information below shows the changes I made to the V0_13 sketch and get a successful compile.   Compiled for Teensy 4 using Arduino IDE: Version: 2.1.0 Date: 2023-04-19T15:31:10.185Z CLI Version: 0.32.2 Errors with unmodified sketch when compiled for Teensy 4  "Sorry, i2c_t3 only works on Teensy LC and 3.x.  Use Wire for Teensy 4.0, 4.1, MicroMod." To fix: Change every instance of i2c_t3.h to wires.h In:  SCD_2021_V0__13.ino Si53...
Read more

Opto-isolated RS-232 for Icom CI-V

Image
First thing I should say, this is my 'design' and I offer no guarantee that it will work for you, be careful if you build one, do your own testing to be certain it's not going to blow up your laptop and or radio, cause a rift in space time and the instant destruction of the entire universe as we know it. OK, guff out of the way, the Opto Isolated CI-V Interface I mentioned earlier, And the schematic! It's rough, hand drawn and there have been a couple of changes to component values, mainly because I found a document that suggests the CI-V interface port on the radio shouldn't have to sink more than 2.5mA, so one resistor has been changed (the 680R on pin 2 of the right hand side opto is now 2K) and another removed completely (the pull up on pin 5 of the left hand side opto) to comply with that. If I short the CI-V line with my ammeter, I get this: 1.6 milliamps, I'm comfortable with that. Currently (yeah yeah) it works reliably as a serial loop...
Read more