Yaesu FT-897D Battery Project

I decided to build a lithium battery for my Yaesu FT-897D because the official Yaesu Ni-Mh batteries are far too expensive to import here (Then you need the special charger too!)

At present when operating portable, I have been running a lithium battery external to the radio (often a higher voltage battery through a little power supply)

So I grabbed some battery packs made up of four 2200Mah 18650 cells each, three of these adds  up to 11.1v at 8.8Ah, this is plenty for my short trips !

I planned out how to fit them inside, and there’s more than plenty of space, see image ๐Ÿ™‚

My preliminary notes were:

The three packs are each four 18650 cells in parallel

Totalling up to 8.8Ah per pack at 3.7v

At full charge it will be at 12.6v and at empty about 9-10v

I have measured how much power the radio draws, and on monitoring it draws around 8w, on transmitting around 18w (at 10w TX power, go figure) so thatโ€™s only 1-2 amps, super easy for these lithium batteries.

I’m just waiting for my BMS to arrive from China (battery management system)

As that has over current protection, over charge protection, over discharge protection and short circuit protection for the batteries

Then I’ll use some padded sticky foam to mount them in such a way they’ll get ventilation from the existing fans and good to go!

Gallery below! 

 

Setting up RTL-SDR in 2017

Years back I discovered RTL-SDR, that used very cheap USB TV tuners to run Software Defined Radio applications.

Back then I found it super easy to setup,

 

You just download ‘SDR#’ and run the installer, then you’re good to go!

More recently though, AirSpy selling their own SDR products, I recall having more difficulty setting it all up..

 

So let’s give it a shot here today.

Heading over to the AirSpy downloads page

I downloaded the ‘Windows SDR Software Package’ which seems to be similar to the old version, containing SDR#, ADSB Spy etc.
This downloaded a familiar looking sdrsharp-x86.zip file

Extracting this zip gives a familiar folder structure, with an install-rtlsdr.bat file, perhaps it hasn’t changed much after all? Not sure why I seemed to have so much problems last time…
I fired up Zadig as admin after it had downloaded and selected Options > List All Devices so that I could find my RTL device.

And with that its time to launch SDRSharp.exe !

The first thing ill do is pop into the options gear up the top there and change the device to RTL-SDR (USB). Then back into options and ensure the correct device is selected and the RG Gain is turned up a little.

And with that, we’re in!

It all seems to be working fine. I did a frequency correction of 3ppm and got it centered on a carrier wave.
Im now able to use this to identify which frequencies are in use around 500mhz so that I can fix up some wireless microphones that are complaining about interference!

 

It was much easier than last time. Not sure why I had so much trouble….

ARNSW Trash and Treasure

This morning I went to the ARNSW Trash and Treasure event!

It’s pretty much a small hamfest!

This is the second time I’ve been to it, it was a bit smaller this time but there was still plenty of stuff. 

It was held at the ARNSW building in Dural
Antenna towers !
There was heaps of oscilloscopes this time, with many costing a mere $10-30!!

There was even this single channel scope with a GIANT display:



The first thing I spied when I was walking around was a small block of foam with 12 nixie tubes on it, it was sitting with a bunch of other vintage tubes. 

I’m a huge fan of nixie tubes so I went straight for my wallet to make sure they were safely mine! Haha
The list price was $120 but I talked it down to $60 for the lot. 

I also picked up a few random metal project boxes that… Seemed to be constructed into things. 

Only one of them was labelled so the other two were real mystery boxes !

Nobody was able to tell me what they were, but I see huge potential in rebuilding them into something else. 
I’m particularly fond of the one with the front handles!!

When I was home I opened up the two unknown ones to find them pretty much empty shells. 

The perfect playground for whatever I turn them into. 


I was also lucky enough to pick up some variable capacitors, which I’ve been chasing for a while. I don’t yet know the value of what I grabbed but it’s certainly closer to what I need than nothing !

I want to use it when building a magnetic loop HF antenna. 

I also picked up a rather nice dial with an easily configurable scale. You just cut out and slide it in. 

Overall it was a pretty successful morning ! 

I spent significantly less than I expected and came home with some pretty nice treasure!

Bonus picture:

Spot the long wire antenna:

Radio Testing!

I went on a mission today to get my HF antenna working with my Uncle’s help!

We started out testing a ‘mini g5vr junior’ off ebay, it was about $50, and… not great.

Its only about 15m at its widest (both elements!)

We couldn’t even get it to tune on any band.

So back to the drawing board, or more the cutting board, we butchered the mini antenna and used its copper wire to repair the G5RVย I already had!

With the two elements from the mini one soldered on, I was still about 40cm short of the correct length, so I cut 45cm of solid core ethernet, stripped the ends and twisted them together, and then soldered that in the mix!

with the two elements the correct lengths (or close enough)

we popped down the road to the park and strung the antenna between two trees about 50m apart from each other, using some rope to reach the trees.

The antenna was only 2-3 meters off the ground, so not ideal, but it was great hearing voices coming through the radio again!

It tunes on some bands, but not others.

I think im done messing around, and ill just buy a new G5RV and not let my parents near it (theyre the reason the one I have now is broken, they didnt even keep the half they snapped off :((((( so much copper just thrown away…)

The park is a good candidate, seems low noise there (compared to elsewhere, I still miss my perk in the mountains though!)

There is two trees with nice high branches I am eyeing off, about 10-15 meters off the ground, and ~70m apart.

If I can string it up between there, and set up camp in the middle of the two, with a little picnic table and some food, I think I could have a fun few hours!

Here is some pictures of the final setup, and a youtube video showing some sweet morse and voice coming through

Antenna Testing

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HamShield Motion Sensor

I am in need of a motion sensor for something, and I have this HamShield that I got from KickStarter recently.

 

heres some code I have mashed together that *MIGHT* make the radio send an SSTV image when motion is triggered..

 

I have to rest it and refine it first! its just mashed code from examples!

TBS Discovery Pro Restoration

Hello!

So this post is going to be basis for a number of updates, essentially I picked up a TBS Discovery Pro quadcopter off ebay for $200 in pretty crummy condition, and im in the process of restoring it to its former glory.

This post is where I will be posting my progress on this, as well as to reddit but eh, this is my turf.

So just for backlog:

Here’s the eBay item page:

http://www.ebay.com.au/itm/231843059723

Here’s two threads on me trying to identify damaged / broken off components:

https://www.reddit.com/r/AskElectronics/comments/47bkdm/can_someone_help_me_identify_this_component_and_a/

So I am restoring this quadcopter….

https://www.reddit.com/r/AskElectronics/comments/46rrf7/can_you_please_help_me_find_a_replacement_for/

View post on imgur.com

 

Can I just take a moment to vouch for how incredible isopropyl is at cleaning these boards? just look at the photos and see for yourself.

Here’s the auction win screenshot:

View post on imgur.com

Finally, here is the album of the photos of my initial disassembly / the damage.

View post on imgur.com

The hardest thing for me is going to be replacing the I2C port on the Pixhawk…

I really don’t know if I can do it, and im worried I’ll mess it up even more..

 

If you’re great at tiny soldering please hit me up if you can help!

The SD card, Iย WAS able to pull flight logs and data from it, but I won’t post it here because it probably reveals the location of the previous owner’s home..

From the electronics I have tested, it appears to work, and the telemetry is a 433Mhz 3DR system. (I confirmed later by removing the heat shrink.

The gimbal motors need replacing, and the main motors need new bearings, the I2c port needs replacing, and the receiver needs its antenna to be fixed or replaced. The top board MIGHT not work, I cant test until the gimbal is repaired. but that would be around $220 to replace im told.

Once these are done, I am confident it will fly once more! (oh and two props are fecked)

Ill also need a new telemetry module, as having one isn’t very helpful ๐Ÿ˜‰

The USB port on the Pixhawk was pretty crusty and unreliable, but ordered this and connected it up and we’re back in business!

http://www.ebay.com.au/itm/251655545391

As I mentioned at the start, Ill update here when I have more to post!

Potential idea for a reconfigurable, portable, HF antenna ?

So I just had an idea, see this:

Portable HF Antenna Idea

Maybe, just maybe, this would work.

you’ll need an antenna tuner because reasons, and probably extra strain relief, but think about it.

need a 10/20/40m antenna?
hook up two 10m cat5 lengths!

you could keep it in a bag, and go off camping or to a field day, forgot your cables?
no prob! head to a nearby electronics store and grab some ethernet of the length you need!

where the cat5 jacks connect to the pl-259, all wires are used in the cat5.

 

JUST DONT GO PLUGGING THE OTHER END INTO ANYTHING HAHAA

DIY Project: Home Automation

Update: This project died when I got a job and can afford off the shelf automation stuff :’)

It might come back when I start adding stuff like blinds and air conditioning control!

 

This project is basically me wanting to be able to automate my house but not wanting to fork over heaps of money for pre made systems.

I’m a bit lazy with details so if there’s any questions you have please comment below!

Newer Update v2.5

Ok, so it just occured to me that I could have bent the antenna down flat so that I wouldn’t have had to make any holes….

 

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As you can see its all in a box now because reasons plus annoying bright light

I got around to making a few changes, I’ll let the images do the talking for me:

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Used spare LEDs to attach the fan, deal with it. Box had a USB 125khz RFID reader in it heh
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Melted the hole for the antenna with soldering iron, then cleaned tip and sliced off excess plastic with stanley knife
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single channel relay board now in use to save space
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my god i did a crappy solder job on this one D:
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dem pro cut outs
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don’t tell me how crappy the fan cut out is. i know.
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cables kept getting caught in the fan so i fixed them.
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close-up of ParaShield with the fan header, and RF module shown.
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the area that I cut out of the proto shield to fit it over the ethernet jack
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used a resistor leg for GND to the RF module, now i can tap into GND from that line as well B)
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blob of blue tack was used to hold things in place while i soldered
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finally, a nice and snug fit, that looks not like shit! xD

 

A few notable things, white LED on ParaShield (I’m calling it that now) has been replaced with a less bright red one. Transmitter repositioned and wired a little nicer, Ethernet hole cut (Stanley knife, metal cutters and pliers).
Proper helical antenna added to both units, Rx unit now has single channel relay.
Also, I shoved it all in a box and added a 12v fan running off 5v from the ParaShield (may add fan controls/monitoring later) so nothing goes wrong with summertime here.
I’m just waiting for the other 433mhz things to add a manual light switch, and the infrared control unit. Codes all ready but need the RF receiver D:

.

Also, on the app side of things,
I added an all on/off section so when this projects complete, I’ll be able to stand out the front of my house, say something awesome, hit a button, and the whole house lights up or goes dark ๐Ÿ˜€ XD

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New update V2
So I discovered this thing:
http://www.ebay.com.au/itm/291262467339

I remember reading about this a while ago but didn’t care for arduino or anything much then.
But now I’m looking at this and seeing
This+Relay+PSU = self contained without need for base controller!
Plus, did I mention ITS FOUR FREAKING DOLLARS
how could I NOT order two!

When they arrive I’ll have a play around see if I can figure out how to control them ๐Ÿ™‚
Will post here when I do!
In other news: I ordered proper 433mhz antennas for the things, and found the PS move squigy ball.
Will get a box soon for it all haha,
I’m also preparing some LED strip on the front veranda to be controlled by my UI. And I’m developing an android app (will design a tablet version later)
Using Tasker app factory!
Early screenshot attached!

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Other photos:

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the two channel relay is sooo bigg D:

Newer update:
I found chunks of a broken PlayStation move controller, for now I’ve soldered some resistor legs to the rgb led breakout board, and have the rgb led on the base station for reasons,

Hopefully further down the track I’ll be able to turn on a mood light fading through, (although once it starts fading how do I stop it…?)

Or even notifications for things!

It also acts as a status light,
On sending an on command it flashes green twice, the off command has two red flashes.
An unused but implemented command gives three orange flashes.

I need to figure out how to flash an error if an unrecognized command is received…

Also I hope to find the sphere from the PS move. And to mount the led on the proto shield, maybe move the rf transmitter to make a cut out for the Ethernet jack,
And then try my luck at designing a special case for it all.
Either adapting an etherten case, or making a shitty one from scratch.
YouTube video showing on/off light
Signal light: http://youtu.be/ejXlYe17N8U

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New update: I got it working again ๐Ÿ™‚
Not sure what was wrong but I rewrote the code and now it works hahaha

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Its a bit slow probably because of the speed I have the radios set to, but oh well doesn’t matter.
I soldered everything together into a little clump, minimising wires, and made a shield for the transmitter so it sits neatly atop the etherten.

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I’ll be able to add other things to the proto shield later ๐Ÿ™‚

Also. Found a leostick under my bed but I’m having issues uploading code to it. Going to use it to make that light switch if I get it working ๐Ÿ˜€

LOOK AT ME I BROKE IT SOMEHOW
Went for a trip to jaycar and bought some supplies, and a smaller soldering iron
When I got home I took down the roof unit, attached shorter cables so it would fit in the little box, and put it back together,
But just my luck, it’s not working now!

I send commands but it doesn’t trigger the relay….

I’ll have to connect it and look at serial monitor to see if it’s getting the command

I’ll also add some code and an LED that blinks when it gets a command….
Oh, and maybe the code to light that emergency light if a pin goes low?

I should probably remove all the pin headers and solder right to the board actually…

Or to a proto shield….

The current state of the project consists of an arduino pro mini clone, that listens on the 433mhz band for a command, and turns on a relay depending on the command.

There is a Freetronics Etherten acting as base station, connected to my LAN, and a 433mhz transmitter, this responds to http requests by sending various commands to the ceiling unit.

Its easy to add additional remote units and set up controls for them, which I plan on doingย  when I get blinds for my windows.

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I also have a raspberry pi running Rasbian that listens for a button press, which is wired to our 20 year old retro doorbell, when the button is pushed the Pi sends a pushover notification to my phone/pebble, as well as plays a doorbell sound throughout the houseย  directly connected speakers.

I’m also going to be setting up Asterix or something on this to add Cisco VoIP phones around the house.

I have plans for an analog control panel too, that has physical buttons connected to an arduino, to send commands to the various other arduino around the house.

For example, a light control panel, push one button to send off commands to all lights in the house, or indivuaul etc.

I also will be adding a sensor to the mailbox, probably solar powered, that sends a command in to the house when mail goes in, either emailing me, maybe a photo?
Sending my pebble/phone a notification, or just lighting up an LED on the control panel to indicate new mail!

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