Posts Tagged ‘40m’
VK3YE homebrew 7MHz SSB transceiver
June 9th, 2015 | 
Author: Steve G1KQH (font, or is it fount (?) of all knowledge) sent me this link of the homebrew 7MHz SSB transceiver by VK3YE:
New Homebrew 7MHz QRP rig from VK3YE
Even lower cost Pixie kits!
Steve, G1KQH has pointed me to a link with 40m Pixie kits at incredible prices. At these prices there is no way the parts could be bought for less than the kit. The version I bought for $10 looks identical. All you need is a morse key, battery 40m antenna and walkman type headphones and you have a credible 40m CW transceiver. It really works.
Yoohoo Roger,
Now I back in front of the Pixie bargain game hunt, after finding the the best price!!!
http://www.banggood.com/DIY-Radio-40M-CW-Shortwave-Transmitter-Kit-Receiver-7_023-7_026MHz-p-973111.html
£2.89!!!!!!!
and if you buy more than 2 it gets cheaper!!
Not forgetting this includes free shipping. Unbelievable.
40m Pixie kit at INCREDIBLE price
I bought my 40m Pixie kit for $10 and thought this was a bargain. Then Andy Cutland sent me this link.
Hi Roger, this is the cheapest i’ve seen yet. What fantastic value !Check out this item I found on eBay:End time: 15 Apr 2015 10:33:10(Sent from eBay Mobile for Android)
At £3.19 with free shipping there is no way you could make this cheaper in my view. Remember this price includes a crystal, PCB and all the board mounted parts. This looks identical to mine which works very well. This is a refined Pixie and performance has exceeded expectations. Netting is excellent TX to RX and AM breakthrough very modest. My power out is about 400mW and a 1uV signal level very good on RX. A totally usable 40m CW rig for not much more than a cup of coffee.
Even with the after-effects of my cerebellum brain bleed I was able to build the kit without any issues.
First 40m Pixie QSO
At 1000z this morning I exchanged RST 579 reports with G6ALB who is 3km from me on my 40m Pixie on 7.023MHz CW. This was my first on-air QSO. Netting was perfect and I used the rig directly into my low Par triband antenna. An ATU might have helped. Andrew G6ALB said the channel was pretty busy but that I was a good RST579 with no hint of chirp. This afternoon we’ll put the rig on his spectrum analyser. I gave Andrew 579 probably reflecting the poorer MDS of the Pixie. I have no idea of his power or antenna.
My initial goals have been met: I built the kit and have managed a QSO on the air with it. With the fatigue associated with my brain bleed still very apparent (I am well and truly shattered currently), I was well pleased. A few more QSOs with the 40m Pixie would be good, HI.
$10 well spent. Excellent little kit. FB little transceiver. Works surprisingly well.
40m Pixie – bench test went well
Well, it took a super-human effort on my part as a result of my extreme fatigue (brain bleed issue) but today I bench tested the little 40m Pixie kit I managed to build earlier this week. It is hard to explain just how exhausting this simple task was for me currently. I now need to recover my energy!
On receive a 1uV signal was perfectly readable and I could detect carrier on/off down to at least below 0.5uV. On TX it was putting out about 250mW into a 50 ohm load. On my antenna it was suffering some AM breakthrough, but less than I was expecting. I was using standard Walkman stereo headphones and a rechargeable 12V sealed lead acid battery. On a small 9V battery I’d expect about 100mW RF out, although this was not tried.
Overall, these results exceeded my expectations: it is more sensitive than I was expecting and the breakthrough of AM broadcasters is certainly OK in the day time. This is of course with no casing at all and no ATU. Using the fitted pot and fitted 1N4001 as a varicap it is easy to get the TX frequency and RX frequency to correspond, often an issue with very simple QRP rigs.
Next stage will be some on-air tests, but it most definitely works. Working the locals should certainly be possible. Sked with G6ALB (3km) arranged for 1000z Sunday on 7.023MHz CW.
UPDATE 2120z: There is a contest in full swing and several Russians and Asiatic Russians copied on the little 40m Pixie. I did not stay on long but there was no apparent BC interference noticeable. So, on a quiet night I should able to use the rig in the evenings. The main issue on RX seems to be the lack of AF filtering, so one has to use “the filter that is between the ears” i.e.the brain.
40m Pixie from AliExpress
From my bank statement I see my 40m Pixie kit from China, that has shipped, cost a little over £7. This includes all parts including crystal and PCB. At this price it would be hard to buy the individual parts. I very much want to build this as it will be the first amateur radio construction here in a very long time. It is sufficiently simple and low cost that I should manage it, even if I am a little clumsy still with the soldering iron.
No doubt Andrew G6ALB (3km) will help with a first test.
New band tried with "compromise" antenna.
This afternoon I tried 80m WSPR with the “compromise” antenna (V2000 + 2m halo with strapped feeders) with some success. On 80m I copied M0BLP and PA0WMR although there were very few stations active. I was not copied by anyone. I was going to try 160m but decided there was too little activity.
Later I used 40m and 20m with the Par end-fed. On 40m, just one transmission resulted in 10 spots in 7 countries. The next transmission resulted in not a single report, probably because I was sitting on the frequency of a very strong station who was TXing at the time?
I later returned to 10m, and spotted EA5CYA (1376km) and LZ1OI (2145km) by Es around teatime. The Spanish station was pretty strong but the LZ was much weaker.
