Archer Beacon ON THE AIR!

[IRONARCHER]

Hello everyone-
I've been a lurker here on HFU for a while now and I finally have something to post about. I'm proud to announce that after a month of prototyping I have finally come up with simple little beacon design that works. Listed below are the specs of the Archer Beacon.

Run Time- 24/7
Circuit design- Simple BD-139 crystal oscillator with an IRF-510 amplifier and 7th order Chebyshev low pass filter.
Battery- Lithium 2 cell pack totaling 8400mah that's charged by 2 small 2.5W solar panels.
Charge Control- I'm using an off the shelf TC4056 charge controller and voltage step up to bring it to 12v for the transmitter.
IC controller- ATtiny85 keys the crystal oscillator.
Power output- About 2 Watts.
Enclosure- Gasket sealed waterproof project box with all connectors sealed with silicone. Added some desiccant packs just to be safe.
Antenna- 64' end fed half wave in a sloper configuration matched with a mini 49:1 impedance transformer.
Beacon Info- Sends "ABK" once every ~55 seconds in slow CW on 6998.73Khz just under the 40m band.
Beacon QTH- North western part of the US.

When the beacon is transmitting the frequency tends to be a bit drifty so it sounds kinda whoopy.
I plan on making a few improvements like a better solar panel and improving the frequency stability.

I would love some feedback on the design good or bad. Just so everyone knows, I'm very much an electronics amateur. The first time I picked up a soldering iron in any serious capacity was the toward the end of 2020 when I went down the rabbit hole homebrewing simple CW radios. I started out building small kit radios and became fascinated with the idea of building a pirate beacon after discovering HFU. The first beacon I actually heard while scanning around was the "Desert Whooper" and I was hooked. After countless hours of research, designing, prototyping, failing miserably, then finally succeeding, I'm proud to present the Archer Beacon.

Please send QSLs to
ARCHERBEACON at GMAIL dot COM
and I will send you a brand new shiny E-QSL card.
If you are interested in the design or would like a copy of the schematic just let me know.
Images attached below.
Enjoy!

[outhouse radio]

i was hearing something way down in the noise but it's high noise level tonight .
give it some time , i'm sure some of these guys on here will get on it soon .

[IRONARCHER]

Yeah it is pretty noisy tonight so I'm not too worried.
I checked out some web SDRs earlier and I could hear it in AZ about 1000mi away so I know it at least works.

[Rob.]

Nice job! Good to see some more HF beacons coming online.

[mark-n-nut]

Doing well here this morning at 1500 utc =/-

73, Mark

[Treehouse SWL]

Hearing it here clearly in Lake Stevens, Washington as of 1920 UTC. I also tried it earlier today (around 1530 UTC) via an SDR on Whidbey Island and heard it there. It is a little whoopy, which makes it sound almost like a bird call at times, which is kind of fun.

Do you want me to email you a short recording?

[IRONARCHER]

Mark and Treehouse SWL-
Thank you very much for your reports! I've sent you my numbered QSL cards.
Any screenshots or audio recording are very helpful and appreciated.
So far the furthest report is from Ukraine!! That blew my mind when I received that report as I never expected it to go international!
Keep the reports coming!!

[outhouse radio]

 Ukraine!

good job man 

[ChrisSmolinski]

Thanks for the new beacon / DX target!

Copied here at 0747 UTC on my overnight SDR recording, using a netSDR and 900 ft Sky Loop antenna.

Below is an audio recording:

http://radiohobbyist.org/blog/mypics/6998.0-USB-22-Jun-2021-07.47.38.mp3

[IRONARCHER]

Awesome! Thanks for the recording as well and my eQSL card will be in your inbox shortly.

[zeak]

Congratulations your beacon is 589 at this location at 0430Z.

Your beacon looks great in the pic posted and the only advice I can give is the outside wiring and critters. Two of the beacons I know of went temporarily QRT simply due to the critters. Other than that, thanks for putting the beacon on the air!!

Receiver KiwiSDR
Ant: 80m dipole at 15m
location:  DM12

[IRONARCHER]

Zeak-
Thanks for the report! If you PM me an email address, I will send you my eQSL card.

Good piece of advice on the external solar power wiring. I can confirm the presence of multiple types of wire eating critters in the emplacement area and now it has me worried. My next trip out I will have to reinforce it with something. The enclosure alone took several days of planning/building and even went through the trouble of a 24hr submersion test to ensure no leaks. I also made sure to consider weather, temporary lack of sun, and high winds into planning but never thought about dang critters chewing up the wire hahaha.

A quick internet search led me to a product amazon carries called "Electriduct 1/4" Rodent Resistant Braided Sleeving" that I think would solve the problem perfectly. If I decide to buy a roll, I will drop a review here for any future beacon builders that may encounter rodent problems. Seems like it would be a cheap solution to prevent unintended and premature QSTs.

[Heathkit]

I'm hearing it right now on the VE7AV SDR, Prince George, BC.

Really chirpy, to the point of musical ^_^

*edit*
Just sent a little recording to you for QSL ID

[IRONARCHER]

Heathkit-
You should be receiving my eQSL card in your email shortly. I sent the email before reading your post so I got your QTH now for my logs.
It definitely is chirpy! I'm not sure how to fix it... I think it is probably a heat problem causing frequency drift. I have a heatsink on the IRF-510 because it gets warm and I tried heatsinking the BD-139 but it made no difference. Maybe ill just leave it alone since the chirp gives it some unique character.
Any thoughts?
Also thank you for the recording. Much appreciated and ill add it to my log.

[Heathkit]

Hi IronArcher,

Thank you much for the QSL!

Looking at the schematic, I'd say regulate the BD-139 (go from 12 to say 9V, then the 5V for the logic after that) and use a buffer. That should cure your chirp.

73's