12v antenna relays - maybe?

 Found some hefty 12v relays from a scrapped car - have a search around your local car breakers!

Might make nice antenna changeover relays...

Click the images to go supersize

Hermes-Lite 2

Made some mods to my Hermes-Lite 2 (HL2).
Click the images to supersize.

Added a power on/off switch to the front panel.

Added DC power socket to rear panel, 9 pin sub D for band data to Hardrock 50 (HR50) linear amp and RF3 input for Pure Signal.

Internals (the lumps in the middle of the power cables are gold plated bullet connectors for easy connect/disconnect)

Isolation milled the HR50 interface (provides band data and PTT)

Pin 2 = TXD Band data (Serial out)

Pin 4 = PTT_IN (in from footswitch)

Pin 5 = GND

and simply added pins for a future second amp interface using i2c

Pin 6 = EXTTR_OUT (out to PA)

Pin 7 = SDA2

Pin 8 = SCL2

Second HL2 in a 40mm case !

Don't shout - WSPR

Homebrew WSPR TX using the brilliant open source code by Harry from Zachtek.
If you want the best, buy from Harry,  https://www.zachtek.com/

I tweaked Harry's code to suit my particular setup(s), initially with a scratchbuilt, single band Tx with GPS - about 200mW out on 40 metres on a 9v DC supply.

I then made a multiband unit using modules from QRP-Labs, including the Arduino shield, si5351 OCXO, relay switch kit and assorted LPF's that all plug into an Arduino UNO.

The OCXO si5351 makes it so much more stable and once warmed up, it doesn't drift - I must try it on 144MHz sometime...

Running at 9v DC in gives an easy 200mW+ on multiple bands, in my case, 4 bands (10, 15, 20 & 40).

It is easily programmed by Harry's excellent Windows software and once the initial settings are done, it needs no further configuration as all important info is taken from the GPS (time, locator etc).

It only needs reconfiguring if you change bands/LPF.

Armbian Linux on a TV box

Armbian on an Android TV box

Follow the 1st post here...

https://forum.armbian.com/topic/26978-csc-armbian-for-rk3318rk3328-tv-box-boards/

It's actually quite easy to wipe out the Android install and put Linux on it, just make sure to use one of the RK3318 flavours to 'burn' onto it.
I run in command line only, but it will run the desktop GUI as well, but it's pretty sluggish.

If you 'brick' it, short the 2 pins in last pic and power on and run multitool again

My post is on page 38 of above link

Chinese RF Power Meter

My Chinese RF Power Meter has self destructed itself !

It's pretty much as this...
https://www.aliexpress.com/item/1005003572858028.html

Simply powering it on one day and the Q2 transistor glowed and let out the magic smoke.

If you have any idea what the original component marking is, I would really like to know as I can't find any detail about this bit of kit. - see EDIT at end of this post.

Click the images to go 'supersized'

The position of Q2 is just below the LCD on the right side and I have circled it's position in red on the next image after removing the LCD - it's a 3 legged device, probably SOT23...

Close up images

Beneath the top left tin screen is an AD8318 detector + circuitry.

Anyone got the same meter and could read the ID on their existing Q2 chip or better still has a schematic?

Please leave a comment below or my email is good on QRZ.com

EDIT:

Testing the AMS1117 5.0 (5v regulator) it had failed and in failing it went input to output dead short, injecting 12v to Q2 - probably why it smoked!
Q2 is/was a 3v3 regulator and tracing the circuit, it's Vout pin is also connected to the 3v3 pin at top right of the board (big clue there!).  Q2's Vin pad is destroyed, but should be simple enough to 'hot wire' to C16.
So, parts are on order, it must be worth trying to save it for the price of a coffee?

3D printed loading coil for HF

 Using a 3D printer to make a loading coil for HF portable or static mobile operation.

On Thingiverse I found some files to download and make a loading coil, by VA3TNE, here
https://www.thingiverse.com/thing:2352109

It is designed to work with a folding 'tank whip' or  'Manpack antenna' or AT-271 folding antenna - Google will bring up some useful links.

I printed both the long and short coil versions and found the short coil best suited my needs as it loads the 'tank whip' anywhere between 40 to 10 metres, which is all I need, although the long coil will tune to 80 metres, but it is very twitchy down there.
The coil wire is 1.6mm stainless wire and the end fixings are 3/8in UNF stainless bolts and stainless half nuts and a brass nut - the long brass nut is for old car exhaust manifods and everything can be found on eBay UK and other UK internet sites.

Tuning adjustment is achieved by a sliding 'short' with fly-lead - I used a Stainless 'Jubilee' clip as opposed to the original idea of a 'crocodile' clip, which is why the coil form has 5 vertical cutouts to facilitate the use of a crocodile clip.
The Jubilee clip is tightened enough to just allow it to slide up or down, but not so tight as to clamp it.

I had a broken camera tripod, so dismantled the broken head and 3D printed a bracket to mount the coil and some radials/counterpoise.  There are 3 short fly wires on the tripod mount and have gold plated 2mm 'bullet' connections for each of the radials, so they easily pull out if someone steps/trips on a radial and easy to disconnect and coil up for transportation.

How it looks on the tripod for portable work (click the images to supersize)

On top of the car with mag-mount

Long loading coil

Short loading coil - my preferred option

The whole package ready to deploy - takes just a few minutes.

I also found that M1ECC is marketing his version of a very similar coil, under the name 'slidewinder DX', here

(Link removed at request of M1ECC-Antennas --> see M1ECC Antenna comment below).

He sells the folding whip seperately, although I got mine from China.