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Freestate Qrp
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Radio Frequency Circuit Experimentation
Radio Frequency Circuit Experimentation

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Project Poseidon - Software for near realtime Space Weather research:

http://markslab.tk/project-poseidon/


I have been ever so eager to share this resource with those who have yet to discover it.

From the website: "POSEIDON is a useful alternative to monitor space weather, HF propagation, aurora and many other things in NRT (Near Real Time)."

What a fantastic, free research tool for amateur radio operators, citizen scientists and anyone wishing to develop a more intimate awareness of the infinite aggregate our world is within.

Take note that Project Artemis is also hosted on the above website. Artemis is a powerful database tool for anyone analyzing radio transmissions. I recommend both tools highly. If you find either of them of use, please share your experience with others.

Project: ARTEMIS

http://markslab.tk/project-artemis/


Project: ARTEMIS

From the website: "ARTEMIS 2 is a useful aid for radio listeners: it allows to compare real-time spectra (from SDR waterfall for example) with those found in archives by comparison of the properties (such as frequency, bandwidth, modulation …) and verifying it through a sample image. A variety of filters allows you to narrow your search, facilitating the identification of unknown signals."

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Creating an Experimental Crystal Triode -

The following image includes extractions from the 1957 publication 'Electronics Reference Data' regarding the conversion of Germanium diodes into transistors. I created the image with the hope that it would be found interesting or influential to my sister & fellow Hombres. I have not attempted to convert a Ge diode nor do I think I would have the capability of doing so.

If this type of data excites you, please visit the website of an incredible experimenter, Nyle Steiner K7NS, at http://sparkbangbuzz.com/ . His experiments in creating semiconductors using basic materials and tools is absolutely astounding! My obeisance to Nyle Steiner, K7NS for sharing his adventures with us. I look forward to attempting a number of them myself.

Thank you for your time & please comment below if you have personally or know of anyone else, such as Jeri Ellsworth ( https://youtu.be/w_znRopGtbE ), who has documented homebrew semiconductor experiments.

Stay fluxy this holiday season, my dear hombres, keep that iron hot and never stop experimenting! _ad0us
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If you haven't yet had the pleasure of enjoying time in the homebrew lab of Ko Tilman via his youtube channel/videos, you owe it to yourself to visit:

https://www.youtube.com/user/radiofun232

This endearing gentleman is a stellar 'digital elmer' and has a unique yet wholesome style of circuit construction. Mr. Tilman also has a number of publications available for sale on lulu, amazon & B&N. He has been kind enough to share one of his ebooks for free via lulu. Even if you are well versed in the complexities of RF design, there is a lot of wisdom throughout his videos. Thank you, Ko, for taking time to share with your sister & fellow Hombres, all the homebrewers of the world.

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From 'Scientific American', Vol 64, Num 14 - 1891
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Freestate Qrp commented on a post on Blogger.
Dear friends, just an update. Ever since discovering 'Scribble Style' I have not looked back. Every single circuit I make on copper clad (buy bulk from abcfab on ebay) has been made using a cheap $2 or $3 scribe. It takes seconds!! SECONDS!! to make a PCB. No super glue, no etchant, no dremel tool or lungs full of FR4 powder. Please, my friends, I urge you to try it!! You will never look back. It is so cheap and easy. I truly believe that some day every homebrewer will be using this scribble style of making PCB's. Look back at that many posts I've made trying to find my style of board construction, I've tried many methods (several not documented here on the blog). If you haven't tried using a Scribe, please do it. Make it your new years resolution to get one & give it a shot. The carbide tip makes it as easy as drawing on paper. The only issue I have had is with very thick layer copper clad, the good news is the cheaper stuff 'scribbles' easy. So please give it a try.

Have you tried it? Troubles? Did it not work? Please let me know. Let's talk about it. Please share the idea with your friends. It is a method of rapid prototyping. Thank you for taking time to consider my words. I wish the best to all in the coming new year.

Keep your iron hot & stay fluxy,
-AD0US ex ke0bff

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Vendors I recommend:
The following recommendations are made without the knowledge of the companies mentioned. I share them with you based on my past exprience. Certain items can be hard to hunt down. While I recommend going to as many hamfests as possible and getting to know any local homebrewers in your area, the following vendors are also a good option.

http://nettyelectronics.com/ - Ran by Earl Andrews ( VE3AB )  and his wife. Earl is such an amazing guy and has helped me out a lot in the past by sharing information on obscure and exotic components, he helped me isolate a problem with a tentec century 21 which led me to a speedy repair and he has sold me some incredible parts for extremely cheap. His junk box/parts bin is open to you and his prices are unbeatable. You will have a blast just looking through all the pictures on his website too. Even with shipping from Canada to the states, I go with Earl/Nettyelectronics for a lot of my parts because the price is simply unbeatable. If you need some obscure part to repair an even more obscure radio, Earl most likely has it. If you need some jellybeans to restock up on, whether transistors, NP0's, magnet wire, heat sinks, NE602/NE612 and other classic ICs, nettyelectronics.com can hook you up for cheap. I really want to reiterate that I am making this (and other) suggestions on my own and without the knowledge of the vendors, I just believe in Earl's service and the parts he offers that much. He tests every part he sends out before it is shipped. He will match transistors for you, wind a toroid for you, whatever you need and at very reasonable cost. See for yourself, http://nettyelectronics.com/


 https://www.midnightscience.net/ - Phil Anderson & his wife run Midnight Science and the Xtal Set Society. Phil Anderson is an amazing and brilliant man who founded Kantronics (before I was born actually, no offense OM, hihi). Phil is a member of my local radio club, DCARC, and has written articles for publications such as QEX and Sprat (just to name a couple). He was recently interviewed on the QSOToday Podcast with Eric ( 4Z1UG ) -- http://www.qsotoday.com/podcasts/w0xi . Visit the MidnightScience.net online store to stock up on items like Air Variable Capacitors or even Planetary Reduction Drives (which I have bought a few of and are of great quality - especially for the price). Again, this recommendation is made without the knowledge of the vendor. It's based on the opinion of my experience with them.

http://kitsandparts.com/ - DIZ: The Toroid King. When talking about vendors of RF parts, one can't forget about the Toroid King himself, W8DIZ. You WILL need toroids when homebrewing. Even at VHF/UHF when airwound inductors are easier and result in better characteristics, it is important to have some toroids on hand, whether powdered iron or ferrite. DIZ also sells other essentials for cheap, such as the popular gilbert cell NE602/NE612 (SA612) in the easy to use PDIP 8 package, and at a very reasonable cost! Don't forget to grab some PIN diodes, NP0 caps, magnet wire, IF amps, JFETs -- (Always good to grab some J310's from him).  DIZ has made contributions to QRP/homebrew magazines as well and plays/played a role in the Flying-Pigs QRP newsletter (highly recommended).

http://www.qsl.net/k5bcq/Kits/Kits.html - Kees is a great guy as well and offers some really interesting kits he has designed. He also offers small quantities of toroids, if you only need a couple of them rather than 25,  kees can hook you up.

http://myworld.ebay.com/abcfab/ - And last but certainly not least is the essential ABCFAB. THIS is exactly where to get Copper Clad for cheap. You can buy a box of many pounds of random cut sizes for about $20 and this will last you years. Copper Clad is the blank canvas that we build upon. It helps to have a lot of different sizes around but if you get a pack of 5 or 10 of a certain size, it will last you a long time. You can use a dremel with cutting disk to cut down to size. Before you order your Copper clad board though, I suggest you get familiar with the different characteristics of the types he offers. Double sided is very good in general but for VFO's you may want single sided. If you etch your boards, single sided may be good as well, but DS is really best for RF. The thickness of the board and the amount of copper deposited is another factor. If you have any questions about it contact him or you can even hit me up and i'll do my best to describe what types I work with and help you decide.  Again, same with all the others, recommendation is based soley on my experience with the vendor.


The above five suggestions are all small 'homebrewed' businesses offering homebrew parts to homebrewers. Again, none of them have prior knowledge of my recommendations and I am not receiving anything for suggesting them, they are good suppliers. I hesitate to name any 'commercial' vendors but it's hard to not suggest the Tayda because I honestly use them for all of my jellybeans and popcorn. A great deal of the Ceramic disc capacitors under 100pF that I've got from them have all been NP0 (black dot - and tested well on AADE L/C Meter) but they are not designated as such on the product page. Their price for 2N3904's 2N3906's, BD139's, IRF510's, Voltage Regulators, just about everything else you are going to need that you haven't been able to find and desolder off of junk ewaste, you can get from Tayda for cheap. I will leave it to the reader to find out their URL via a google search however. You can choose the slowest cheapest shipping from Tayda and spend $10 total and wind up a fully stocked inventory of parts in less than 2 weeks. One note however is that I've noticed certain items will delay the order by a great deal. When ordering protoboards, copperclad, or enclosures - the order has usually been delayed and I assume it is because it first comes from overseas to their warehouse and then to the end user, but I have not confirmed this. Their potentiometers are dirt cheap $0.50, and also pickup some Rotary Switches, super cheap. I think they market more towards folks that build audio circuits and guitar effects circuits. Their prices are good and their shipping fast (and cheap). Another bonus is that customers can rate and leave comments about products on their website for others to see.

Well, just wanted to make a quick informal post. Check out http://freestateQRP.blogspot.com/ for more info on homebrewing. Best of luck to all the guys and gals out there playing with electrons. Keep your iron hot and stay fluxy!

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Scribble Style
Greetings Hombres *  Today I would like to share with you how I have been making my RF PCBs lately. I have documented several different methods of PCB design I've tried in my previous blog posts. However, with this new technique that I like to call the "Scr...

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Here you can see the output transformer, (30T:4T on T37-2) of the variable crystal oscillator (switched crystals with AIT offset adjust using air variable dialectric capacitor that will be panel mounted). To the bottom left of the transformer is the 50-ohm delta configuration -6dB resistive power splitter that takes the oscillator output and feeds it to the input of the NE602 and to the keyed driver staged. The output is ~10mW and so far the tiny SMD resistors haven't caught on fire. I think they should be just fine but I wouldn't use them on the output of the PA.
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