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The $4 Chinese Pixie Transceiver.

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gil:
Hello,

Can you really get on the air for $4? Absolutely! Well, for the transceiver anyway, which in this case will cost you less than the wire to make the antenna. I bought a Chinese Pixie kit for 3.50. That's less than $4, shipping included. Can it even work? Yes. The kit is pretty much as simple as you can make a transceiver. There are two transistors and an audio op amp, three diodes, that's pretty much it. The kit is very easy to assemble and a very good first project. You don't get a keyer, filter, not even a sidetone, but it does receive and transmit on the 40m band. The included crystal is for 7023kHz. When finished I was left with two extra capacitors. I am not even sure of C10, because the one I used had smeared markings, but it doesn't seem to affect anything. The variable resistor supposedly adjusts the frequency slightly but I didn't mess with it. There are no toroids to wind, though I can't understand why anyone would shun doing it as I find it very easy and relaxing.



Video below is still processing... Check back in a little while...



I plugged the kit into my 135ft Windom and started calling. No answer, but a bunch of stations a few hundred miles away reported me on the Reverse Beacon Network, some at 13db over noise floor, which is amazing. Not bad for a 300-500mW transceiver. I lost my QRP Wattmeter, so until I get a new one I won't know. I will try to make some contacts again when I have time. If you don't mind the lack of keyer and sidetone, this transceiver is pretty good. Some call it "dismal," I wouldn't go that far. Sure, a Rock-Mite beats it, but it's also $50, more than twelve times the cost of the Pixie! Really, for less than the price of a Frappuccino, who would not want to build this kit? It takes no space at all in a bug-out bag and weighs nothing. Add a tiny end-fed tuner, 65ft of thin wire and a 9V battery and you're all set! You can use earphones and a tiny home-made key.



I wasn't going to put it in a box, but I changed my mind given that it actually works. I might get a 7030kHz crystal later. I'll use a simple push button for a key and that's it. I'll add a 12 mono-band transformer from EA3GCY http://ea3gcy.blogspot.fr/2016/04/mef-1-monoband-qrp-enfed-tuner.html to make a tiny 40m emergency station. I should have bought three or four! :o Well, it isn't too late...

Gil.

cockpitbob:
Nice.  I remember reading that the Pixie has a cult following with people doing lots of mods.

So Gil, I'm curious, did you consider the Frog Sounds rig?  I know it's about 3x the cost ($12) ::) but it seems a more capable rig:  side tone, almost 2W, volume knob, output filter, real audio amp and super het circuit(I think). 

Watching with interest :)

gil:

--- Quote ---So Gil, I'm curious, did you consider the Frog Sounds rig?
--- End quote ---

Definitely, I will get one too. At $12, I don't see why not... :D

Gil.

gil:
Thanks to Bob my Pixie now looks awesome ;D



I tuned it tonight using the following procedure:


* I called CQ a few times and looked at the Reverse Beacon Network, got reported at 7023.1kHz.
* I set my KX2 to 7023.1 and started an audio spectrum analyser app on my phone.
* Tramsmitting with the Pixie I noticed the sidetone was 667Hz.
* Transmitting on the KX2 I turned the adjustable resistor on the Pixie until the spectrum analyser app showed 667Hz.
* I called CQ on the Pixie, now reported on 7023.0kHz.
The adjustable resistor on the Pixie only slightly changes the TX frequency but wildly changes the RX frequency. My goal was to match the two tones so that I am listening to the frequency I transmit on. As a bonus the TX frequency moved down to a perfect 7023kHz.

I did not make a contact tonight but it is apparent in the report from the RBN that it isn't a transmission issue but a receiving one. The Pixie having no filter, I could hear so many signals tonight that I could barely decode any single one. I think I heard my call sign returned but couldn't be sure. I guess I'll have to wait for a quieter band. I was thinking of getting a 7030 crystal, but that would make it worse, 7023 is fine, not too crowded. If I was using a magnetic loop antenna I might want the 7030 crystal, but not with a regular antenna.



OH6BG reporting me at +22dB over noise is a station from Finland 1100 miles away! Not bad for a $4 radio ;D
Antenna was my 135ft Windom with dual-core Guanella BALUN, 10m of RG-174 plus 5m of RG-58.

Gil.

gil:
Another try with the Pixie:



Which shows again that the little transceiver has no trouble getting out. I am however not getting any replies. The problem isn't about transmitting but receiving. With no filtering, it is very hard to determine if someone is actually talking to you unless they repeat your call sign... Oh well, it is fun trying!

Gil.

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