Homebrew: The N1TEV Regen Build – Part 1
Today I picked up some parts to start the build of my N1TEV regenerative receiver. Checking online I found that Far Circuits makes a board that is ready to go for this project. His website and ordering process are definitely old school. He really needs to make a better e-commerce web site. Basically ordering from Far Circuits sucks, but the boards are nice and I picked up two of them. One for Jeff N9IZ and one for myself.
I went by RadioShack today to get some of the parts. I couldn’t find all the parts locally, so I had to scavenge about a bit and look for some parts that I had lying around the shack. This ended up to be a good thing, because I had several of the capacitors lying about. Like a mondo 100V version of a .047 uF cap that really just calls for a 50V small cap. The legs of that cap were a bit thicker since it can handle double the voltage, so I had a bit of a struggle getting through the holes on the breadboard. RadioShack is really pretty expensive for parts, so if you have bits lying about I would suggest you use them.
I would say that I am about 40% done with this project. It took me about an hour to do this much, and that was with the scavenging about to find some of the caps and resistors. I had a blast soldering these components to the board. It was nice to smell the familiar scent of rosin and solder again if just for a little while.
On the plus side I found a great site to look up resistor color codes to find resistor values here. It is very simple but effective. I found another site that will tell you the values for those small disc caps on Elecraft’s page here.
Looks like I’m going to need more parts that I don’t have lying about so off to the internet for those. I need a variable capacitor, a good enclosure, knobs and miscellaneous goodies still. Jeff (N9IZ) sent me a link for a site for some great vernier turning dials that I think would be awesome for this project.
I plan on using a BNC connector for the antenna connector. I think that would be a good solid choice and I have a chassis mount one of those around I think.
RadioShack did not really have anything good in the way of enclosures so I stopped by another electronics store in town called Lafayette Electronic Supply, Inc. They have a great selection of stuff, but holy utility belt Batman are they EX-PEN-SIVE!!! The enclosure I liked was $40. $40!!! can you believe that for a empty metal enclosure? I thought that was just way too beaucoup expensive for that and will either look around online or make one from copper clad boards which a lot of people have done building regens like this. I walked out of Lafayette Electronic Supply without buying a thing. For the prices they charge there you would have to give blood or take out a loan to build something. I could have bought 4 AM radios for the price of the enclosure alone. Horsehockey! as Col. Potter once said.
The build was fun, but all good things must come to an end, at least for today. Stay tuned for Part 2! I’m really having fun building this and it is going to be awesome once I get to hear my first scratchy reception of a HAM or SW broadcaster.
73! de Nick N9SJA
Pretty cool project i have a reciever from Ten tec nice little rigs. I have made some changes to my blog so check it out when you have time!
Hi Nick,
I’ve finished my receiver and stopped by to tell you about it. I have to say I’m disappointed in its performance, as it suffers from extreme hand capacitance. If I were to build another one I’d set the controls far behind the front panel with nylon shaft extensions.
Tuning with the 365 mmfd variable capacitor is VERY sharp and you need a bandspread cap. The one I used has one rotor plate and one stator plate which works pretty well.
It was a fun project but I think I’ll look for a better circuit.
I’ll send some photo’s if you send me an email address.
Mike
Mike,
Too bad that you were not happy with it. I have heard that the hand capacitance issue was a major problem with these. I got an all metal box for mine, so I was hoping that might help.
I would say that I’m about 80% done with it. I got busy with work, so I haven’t had time to work on it too much. The thing that I really hate about building projects are that the parts are astronomically high. I could have bought a multi-band shortwave receiver for the money that I paid for the parts.
RadioShack is just too damn high, and I hate shopping there anyway since the sales staff usually doesn’t give a damn about a guy buying parts.
Finding the variable caps was a challenge also, I had to order them from some guy on e-bay since those are really not used in modern electronics too much.
I like building stuff, but I think I will scavenge a bit more next time.
Are you a ham? How did you stumble onto my blog if you don’t mind me asking. Mostly just a few buddies read it, so I was surprised to see a few other guys comment on here.
I would love to post your pics on here of your build if you would like to send them. My e-mail address is nicholashyer-at-gmail-dot-com (you will need to insert the @ symbol and the .com part – I do that because there are spammers that crawl comments on WordPress blogs to attack them with spam.) I don’t know if it helps anymore but ok. I should put a submission form on here for stuff, that would be easier i think.
Good to hear from you! 73! de Nick N9SJA
PS: hand capacity effects are normal. This is an oscillating detector. You require a metal front panel of aluminium or copper clad board. If you use a 365 pF tuner, the value for bandspread I found optimum is about 17 pF. I was using Jackson capacitors, no longer made, but the US ones are near enough the same. Also, use a slow motion drive on the tuner!
Hi gents,
Re my PS: the circuit is a diode detector with regenerative RF ampifier, I wasn’t looking at the circuit at the time, sorry about that, I had the idea it was one of N1TEVs other regens.
The three series diodes, as I understand N1TEVs articles, are for voltage stabilisation of the RF amplifier. His other articles say why it’s necessary. It’s worth looking them up.
Variable capacitors can be had from Oren Elliott Products and the Xtal Set Society. Budget cases can be seen in Ten Tec’s T/TG series, and more professional (and more robust) cases can be seen in their BK – BU range.
Good Luck,
Peter
Hi Nick, I’ve sent some photos of my regen radio.
In answer to your questions, no, I’m not a ham, but I like to listen to you guys. I’m a bit of a SWL. I’ve got a Grundig Satellit 800 and an older Sony ICF-7600D. They both pick up SSB. (as does the Kitchin regen)
I found your blog with Google by clicking on the schematic of the Charles Kitchin regen radio. Apparently Google has indexed the picture you posted.
I thought it was way cool that somebody else was building one at the same time I was.
What interested me was the 1N34 crystal detector, since I’m a crystal set fan. I built my first crystal radio in 1966 when I was 11 years old and never lost interest. Somewhere I have a letter written by the great one himself, Elmer Osterhoudt.
Mike
Pingback: K8TND’s Take on the Kitchin Regen « N9SJA
Hi,
Just started making this Regen fo my daughter to take to physics class in school, made my own PCB, going well so far, if you thought $40 was expensive for the case take a look at the prices for the verniers you mentioned, If you add the case to 3 or 4 verniers it well over $150 !!!!!, recon I will stick to plastic knobs!!
David, yes I have found that building projects like this are actually really expensive. The old days of saving a few bucks building your own stuff are over. You really can’t build very many electronic projects from scratch anymore and save. I think the reason is that a lot of these components are not widely made or made inexpensively. For example, variable tuning capacitors are not used in even cheap simple radios anymore. It’s all surface mount, microprocessor and software. I don’t think that’s a bad thing, just the way progress has taken the project builder. Good luck to you on your regen. I’m sure your daughter will love such a quant gadget in this world of iPads, iPhones and ultra books. Check the other info out on regens on my blog, K8TND Cliff has a lot of great info on a recent post I think you will like. 73! Nick N9SJA
Nick,
Many thanks for that, K8TND’s version looks great! and the tips from others make interesting reading, a few pointers i will certainly incorporate in my version! I’m almost inclined to start over with the revised schematic it looks a lot simpler! or maybe make both and do a comparison!…………i have enough parts…….
Hi NIck,
I came across your interesting and informative website during a google search for updates on the Kitchin regen radio in the article “A Simple Regen Radio for Beginners” that you and others were building about a year ago. This radio could be the most popular regen circuit in the 21st century due to its simple of construction.
Can you mention if you completed your radio and what your impressions are on performance and operation? I could not find “Part 2” of your report on it.
I built this radio as published in the QST article with the FAR circuit board in 2002. While it did work, I found it disappointing in performance and operation – not as great as the article alluded it would be. In spite of this, I used it in the local Boy Scout merit badge program because of its simplicity and low parts count. About 30 scouts have duplicated it of the last 10 years or so. It does a good job of introducing youngsters to electronics and homebrewing by making their “first radio,” and it is better than having them make a “do nothing” box that flashes colored LEDs. Though it did work and the scouts thought it was a great project, it is not a very good receiver except for the strongest SW stations. For many years I thought that I had been doing something wrong, like my leads were too long or in the wrong place, because several web sites raved about it, especially as a youth project. However, over the last few years, I did notice that others shared my disappointment. A rather humorous story about the Kitchin radio is at geojohn-dot-org in which the author substituted a JFET transistor for the bipolar 2N2222 and made some other component changes. I did this and the JFET made a significant improvement in reception of weak stations and CW, and in the regeneration control.
Incidentally, I found that hand capacitance can be minimized/eliminated by using an all metal (like aluminum, copper, copper coated circuit board or thin sheet steel) front panel and grounding it to the circuit board ground. For the scouts, I have been using 4×6 copper circuit board material for the panel with no hand capacitance effects.
73,
Tom
WB2STR
Tom,
Yes. I did complete the build. I never made a post showing the operations, perhaps I should do that. The receiver does have poor performance, and the hand capacitance issues are a plague. If you check the comments there are lots of improvements made by another ham that posted on my blog named Cliff Donley K8TND. You can find all the posts about the regen stuff on my blog just by typing in “Kitchin” in the search box. He had modified the original circuit for much better performance he claims. I myself have not tried his mods or anything. I am more of a DXer and general experimenter so I kind of gave up on tweaking or messing around with the regen receiver. For me it was a one time fun project and that’s about it. Cliff is a regen receiver connoisseur, he builds these receivers all the time and is the best expert I know to help you if you have any questions. He should be good on QRZ.com, again his callsign is K8TND.
Hope that helps. 73! de Nick N9SJA
Mine worked awesomely. Had no problems. I donated this one to the Los Alamos Amateur Radio Club. I have one more board and will make another one day. These boards were given to me by someone else.