QRP Results in the January VHF Contest

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The July issue of QST arrived in the mail recently with an article on the January VHF Sweepstakes results. It always takes about 6 months to have the scores show up in QST, so some people make it a point to share their scores via email and figure out who won. I just submit my log and then forget about it until the scores get published, which means I have usually completely forgotten about the contest by then. It can make for a nice surprise when the article gets published.

This year I reverted back to my “hike up a local mountain and operate QRP” operating style. The past few years I have been more of a slacker, operating from the comfort of our cabin up in the mountains. The backpack portable approach is a lot of fun but does limit how many hours I operate and therefore keeps the score on the low side. I am not about to freeze my behind by spending the night on the mountain in January. It does make for a fun hike, often requiring snowshoes to make it up to the summit (but not this year). My soapbox comments, including a few photos, are on the ARRL web site.

So I opened QST and found that I absolutely dominated the Rocky Mountain Division with my 741 points :-). Here’s the list of Single-Operator Portable scores for the entire contest:

# Call Score QSOs Mult Class Section
1 N3YMS 32,184 260 72 Q DE
2 N8XA 6,864 123 48 Q OH
3 W9SZ 2,268 38 28 Q IL
4 WB2AMU 1,518 63 22 Q NLI
5 K9TMS 1,420 46 20 Q EB
6 K0NR 741 39 13 Q CO
7 W0UC 380 19 10 Q MN
8 N0HJZ 192 12 4 Q MN
9 KC8KSK 138 17 6 Q NC
10 N0JK 80 10 8 Q KS
11 K1EXE 60 12 5 Q VT
12 VA3RKM 56 9 4 Q ON
13 K9PY 50 8 5 Q AZ
14 KD7WPJ 48 6 6 Q UT
15 KB2AYU 45 9 3 Q EPA
16 WA1LEI 39 13 3 Q CT
17 W0DJM 35 5 5 Q MN
18 K7RLL 15 4 3 Q VA
19 W6MDH 12 3 3 Q EB
20 N3RG 8 1 1 Q SNJ
21 WA3WUL 8 1 1 Q SNJ
22 W6CT 4 2 2 Q SCV
23 K2ULR 1 1 1 Q GA

The competition in this category is a mix of activity ranging from very serious efforts (e.g., N3YMS with over 32,000 points) to people that just make a handful of contacts. It turns out I placed 6th overall. I didn’t enter the contest to win, but I have to admit it is nice to know there is a category where the Peanut-Whistle Stations don’t get swamped out by the Big Guns.

If you want to try something different, give VHF QRP a try in one of the contests.

73, Bob K0NR

USB Cable Experiment

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Given all of the electronic gadgets in my life, I end up carrying quite a few cables and power adapters around with me. Somehow these things always end up in a tangled mess inside by backpack/computer bag. It often takes me days to untangle them after a trip. Although annoying, I didn’t really give it too much thought as it just seemed part of having all these gadgets.

This weekend, I decided to apply the scientific method to aid in my understanding of how these cords get tangled. I did a controlled experiment using two USB cables carefully laid on a flat surface a few centimeters apart:

I left the cables in a locked room, with windows closed so that wind or other outside forces could influence the outcome. The above photograph was recorded at 9 PM on Day 1.

The next morning, I returned to the room and verified that the door was still locked and that nothing had been disturbed. To my surprise, I found the two cables in this condition, recorded by photograph at 9 AM on Day 2:

Apparently, the cables are able to move on their own and create a tangled mess without human intervention. There must be some physical force present that causes this movement, perhaps the triboelectric effect? I will need to repeat this experiment, perhaps with a video camera capturing any movement.

Has anyone else produced similar results?

– 73, Bob K0NR

This Spewed Out of the Internet #15

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It’s time to do one of those miscellaneous collections of drivel that spews forth from the interwebnet pipes. Some of this might even be important!

Some upcoming events: ARRL June VHF QSO Party and the Colorado FM Sprint, on the weekend of June 12th. The FM Sprint runs concurrently with the ARRL contest but only on Sunday afternoon. This is a good chance to get on the air with very basic equipment and have some fun.

The ARRL Field Day is coming up on June 26th and 27th. This is arguably the biggest on-the-air amateur radio event in North America.

I was playing around with setting up an SMS text messaging system for callsign lookup. The idea is that you send a text message (containing an amateur call sign) with your mobile phone and get the FCC or QRZ info back. In the meantime, I found that this problem has been solved by Callsign By Text. Very nice, check it out.

Female radio amateurs should check out Chick Factor International. It looks like a fun group.

I picked up a DV Access Point (DVAP) for D-STAR. This is a neat little device that provides flea-powered D-STAR access on 2 Meters by plugging it into a PC with internet connection. The South Yorkshire Repeater Group has a good description of the product. So far, this thing works really well.

By the way, the South Yorkshire group has a really good web site…interesting and timely information. Although they are in the UK, I find it relevant to US ham radio activity, too.

The Technician Class License question pool will be updated as of July 1, 2010. Our next Tech Class in Monument will be in October, so we’ll be updating the classroom material before teaching that class. It is clear that more technical content is being added to the question pool, which I think is a good thing. See KB6NU’s posting on the topic.

From The Complete Waste of Time Department, the FCC once again dismissed a petition from K9STH to change the amateur radio station identification requirements. Look, the FCC doesn’t see a problem here (and neither do I) so save yourself the trouble.

The FCC is seeking comments on the proposed new rules concerning emergency communications.  I took the time to file a short comment, basically saying that the FCC is on the right track but they should remove the reference to “government-sponsored drills”. Any legitimate emergency communications drill should be included, regardless of who sponsors it. The ARRL made similar but more detailed comments.

– 73, Bob K0NR

Update on the IC-9100

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Ham radio VHF enthusiasts have been patiently waiting for the ICOM IC-9100. This HF/VHF/UHF/Satellites covers most or all of the popular amateur bands. Recently, ICOM has posted the specs and brochure on its web site.

The rig has dual receivers that allow monitoring two bands at once and it is set up for full-duplex on satellites. The built-in antenna tuner covers HF and 50 MHz. Operating on 1.2 GHz requires an optional module.

There is an optional DV (D-STAR) option that works on 10M, 6M, 2M, 70 cm and 1.2 GHz. This is the first combo HF+VHF+UHF rig that has DV available.

The 100 Watt output power all the way up to 50 MHz and 144 MHz is a real plus and 75 Watts on 430 MHz is not bad either. The 1.2 GHz option would be nice, too. This would be a great radio for portable VHF contesting. Oh, and I guess it works HF, too. 🙂

So everyone was expecting a big ICOM announcement at the Dayton Hamvention. Based on the reports I heard via the D-STAR system in Dayton, one unit was shown “under glass” so attendees could look but not touch. Also, a number of people have reported that the ICOM booth staff are saying that the 9100 will be available later this year (fall timeframe?) at a price of ~$US 4000.

Ouch. Most observers see that as a bit too expensive. I’ll withhold judgment until it is really in stock at a dealer with a real price.

–   73, Bob K0NR

SWR and Return Loss – There’s an Ap for That

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For the RF/microwave enthusiasts out there, you may recall the old HP Reflectometer Calculator that does conversions between SWR, Return Loss and calculated mismatch uncertainty.

Well, fast forward to the 21st century and this same functionality can be found in an iPhone ap. Agilent Technologies has a free ap available on iTunes that does these calculations and some other things like decibel conversions.

Check it out at here or just search for microwave calculator on iTunes.

– 73, Bob K0NR

Announcing the Colorado FM Sprint

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The Colorado FM Sprint is a short and simple VHF contest that runs in parallel with the ARRL June VHF QSO Party. Basically, it’s a chance to have some fun on the VHF bands for not-so-serious contesters.

Sponsored by:  Colorado ARES and the Colorado VHF Group (KØYB)
Direct any questions to k0yb@qsl.net

This contest is held concurrently with the ARRL June VHF QSO Party, with compatible rules and operating procedures. The purpose of this contest is to:

·        Promote the use of FM VHF/UHF simplex

·        Provide an opportunity for radio amateurs to test the limits of their stations using FM VHF/UHF and to experiment with ways to improve their stations

·        Practice deploying portable and mobile operation as a means of identifying effective locations for temporary relay stations

·        Provide a simple and enjoyable radio contest experience (“Have fun!”)

Time:

Sunday, June 13, 2010; 1200 to 1600 Mountain Time (1800 to 2200 UTC)

Objective:

To work as many stations as possible using FM simplex on the 146 MHz, 222 MHz and 440 MHz bands in as many different VHF grids as possible.

Frequencies:

Operate on FM simplex frequencies consistent with the Colorado Council of Amateur Radio Clubs (CCARC) band plans with special emphasis on using ARES designated frequencies.

(Consistent with the ARRL Rules, 146.52 MHz is not allowed to be used in the contest.)

Suggested Frequencies:

2 Meters: 146.58, 146.55, 146.49 MHz

222 MHz: 223.5 MHz

440 MHz: 446.0, 446.025, 446.100 MHz

Do not operate on repeater frequencies or 146.52 MHz, the National Simplex Calling Frequency.

Remember to be a considerate operator and share the frequency with other operators.

Contest Exchange

To complete a contest QSO, you and the other station must copy each other’s callsign and 4-digit Grid Locator. You may optionally exchange Name and ARES District.

Note: These are an abbreviated set of rules…the complete rules and FAQ are at http://www.qsl.net/k0yb/Colorado_FM_Sprint.html

73, Bob K0NR

Bob’s Rules for A Fun Radio Club

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The other night, I attended one of those unfortunate, but all too common dysfunctional radio club meetings. (The name of the club will remain confidential.) You have probably been to one of these sessions where the leadership of the club is frustrated because they feel like only a few of the members are doing all of the work. The other folks may come to the meeting but are reluctant to sign up for anything.

The topic of discussion happened to be Field Day. The plans in place were not coming together and the leadership was getting frustrated. My point of view was quite simple: if no one wants to help with Field Day, then let’s not have Field Day. Heck, this radio club stuff is supposed to be fun. If we are trying to make activities happen that people don’t want to support, then we are probably off in the weeds.

This caused some of the folks to raise their hands and say “yes, of course we should do Field Day and this is how I can help.” So things are probably on track for now. Maybe.

This situation is not unique…most clubs (of any kind) have the core group that does most of the work and the secondary group that does much less. Sometimes the players change depending on changing circumstances such as family and work obligations, but the structure tends to remain.

I came up with a couple of simple rules to avoid frustration in this kind of situation:

  1. Don’t volunteer to do anything that you aren’t personally motivated to take on. If you aren’t doing it because you truly want do, then you’ll end up resentful if other folks aren’t “doing their fair share.” It’s a volunteer organization, after all.
  2. Don’t expect others to sign up for volunteer work because you think it is important. Their priorities might be different and it is totally their decision (see Rule 1).
  3. Lead, Follow or Get Out of the Way. If you want to make something happen, get out in front and lead. If you don’t want to lead, then follow. Commit your own time to making it happen (see Rule #2). If you can’t lead or follow, then stay out of the way.

I get enough of this “gotta do it” stuff at work. Ham radio should be fun.

What do you think?

73, Bob K0NR

AM, FM, WX and 2-Way Radio

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A few weeks ago, I woke up to find that the power was off at my house. It so happens that most of the fun electronic stuff in the house doesn’t actually work when the power is out. The most critical thing is that the freaking internet didn’t work. Huh?

I remembered that I had purchased one of those whizzy emergency radios that has a hand-crank generator built into it. After I fumbled around and found it stuffed away in a closet, I gave it a crank and the radio receiver came alive! Wow, instant communications without batteries or AC power.

I got to thinking that we should have one of these radios at the cabin up in the mountains. After all, the power goes out there even more often.

Searching around Amazon.com and a few other sites, I discovered that the Midland XT-511 Base Camp radio has a hand-crank radio that includes AM broadcast, FM broadcast, Weather receive and, yes, a GMRS 2-way radio. OK, it doesn’t work on the ham bands but the FRS and GMRS frequencies might be useful when things go dark.

It arrived the other day and, so far, I am very pleased with it. It is a consumer grade piece of radio gear but it seems to perform well. I tuned around the AM, FM and Weather bands, clearly receiving the stations that I would expect to hear. The GMRS radio seems to work OK but the transmit audio was a little mushy.

The radio can operate off of the internal rechargeable batteries or standard AA alkaline batteries…quite flexible, I’d say.

The radio costs around $56 from Amazon.com.

73, Bob K0NR

Results from the Second Technician Class

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We completed our second attempt at the Technician License Class. The format we are using is two all day Saturday sessions, supplemented by self-study using the Gordon West book. We had 14 people take the Technician exam (Element 2), with 13 passing (93% pass rate).  We had 4 Boy Scouts in the group and they all passed. (Their troop is getting quite a few Scouts with licenses and they are having a blast with it on camp outs.)

The 2-day formula seems to be working, so we’ll do it again in the fall. Summer seems like a good time to lay low and we will need to rework the material due to the new question pool for the Tech exam. At first glance, it looks like the new question pool is a little more difficult as it includes more advanced technical topics.

The next Technician Class will be held in the fall, tentatively scheduled for October 16 and 23.

73, Bob K0NR

This Spewed Out of the Internet #14

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Happy Easter!

A few posts back, I wrote about podcasts worth listening to. I want to draw your attention to two additional ham radio podcasts:

  • Teen Radio Journey by Paul KC9QYB, available on iTunes or at http://www.teenradiojourney.com/ This podcast is intended for teenagers, so I am definitely outside of that target audience. I mention it here because anything that involves youth in amateur radio is a good thing.

I just stumbled onto the radio contesting site radio-sport.net. It has probably been there for decades and I am late to the party. It is worth checking out if you are into contesting.

I went through the entire day without thinking about buying an iPad. To quote Joey from Friends, “its all a moo point.” Even if you do want an iPad, why would you buy the first implementation, given Apple’s track record? There will be a better one coming along soon enough. Take a look at the Fake Steve Jobs blog.

The high-powered think tank at the Fi-Ni Report has published some brilliant work:

  • The investigative team has uncovered yet another scandal in the radio sport world, this time relating to the Poisson d’Avril Contest
  • AM (Ancient Modulation) is getting a strong endorsement from the CQWW Contest, pushing aside that sissy SSB modulation

73, Bob K0NR

Ham Radio Two-Day License Class – New Session

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Building on the success of our first Technician License Class, we are offering it again:

Ham Radio Two-Day License Class

Monument, Colorado

Saturday Apr 24 and Saturday May 1 (8 AM to 5 PM)

Location not yet finalized

Sponsored by the Tri-Lakes Monument Fire Radio Association

The Technician license is your gateway to the world-wide excitement of Amateur Radio …

  • Earn your ham radio Technician class radio privileges
  • Pass your FCC amateur radio license exam right in class on the second day
  • Multiple-choice exam, No Morse Code Required
  • Live equipment demonstrations
  • Learn to operate on the ham bands, 10 Meters and higher
  • Learn to use the many VHF/UHF FM repeaters in Colorado
  • Find out how to participate in emergency communications

There is no cost for the class

However, students must have the required study guide:
Gordon West Technician Class guide $18.95
And pay the FCC Exam Fee: $15.00

Advance registration is required (no later than Apr 17th).

To register for the class, contact: Bob Witte KØNR   techclass@k0nr.com

For more information on amateur (ham) radio visit www.arrl.org
 or www.wedothat-radio.org

FCC Moving Ahead with EmComm Changes

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fcc-1The FCC has released a Notice of Proposed Rule Making (NPRM) concerning use of amateur radio by employees of governmental and other agencies. I had previously posted my thoughts on this topic back in October 2009.  A read of the NPRM on the FCC web site reveals that the FCC clearly sees this as an issue that needs to be addressed.

The tone of the NPRM is “what is the best way to address the problem” rather than “should we address this issue”?  In fact, the FCC went ahead and proposed this specific rule change for Part 97.113:

§ 97.113 Prohibited transmissions.
(a) ***
(3) Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer, with the following exceptions:
(i) A control station operator may participate on behalf of an employer in a government-sponsored emergency preparedness or disaster readiness test or drill, limited to the duration and scope of such test or drill, and operational testing immediately prior to such test or drill.
(ii) An amateur operator may notify other amateur operators of the availability for sale or trade of apparatus normally used in an amateur station, provided that such activity is not conducted on a regular basis.

The ARRL article concerning this development provides a good summary of the proposal. N5FDL has a brief discussion of the NPRM on his blog. Comments can be filed electronically on this NPRM on the FCC Electronic Filing Comment System.

I think this is moving in the right direction.

– 73, Bob K0NR

Podcast Signals and Noise

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step1_ipodnano_whiteI’ve posted before about being a fan of podcasts (those mp3 file “radio shows” that don’t use radio). There are so many decent podcasts out there to choose from, I keep my iPod Touch loaded up with all kinds of mp3 content. Actually, my taste includes topics outside of tech, but that is what I’ll focus on for this blog posting.

One thing I have noticed is that the ham radio podcasts on my mp3 player are getting pushed aside by other tech shows. I think it is driven by the signal-to-noise ratio of the ‘cast. With so many to choose from, I have become less tolerant of rambling commentary, crappy audio and marginal content.

I don’t want to be overly critical, since it takes real work to produce a quality podcast. I have enough trouble keeping up with this blog. I would not be able to do a decent job of an audio podcast and you probably don’t want to hear my voice anyway. (I have a radio face and a CW voice.)

So what am I still listening to these days? Here’s my favorite tech-related podcasts, in rough order of priority:

  • Amateur Radio Newsline
  • Buzz Out Loud (CNET)
  • Cranky Geeks (John C. Dvorak)
  • This Week in Tech (Leo Laporte)
  • Slashdot Review (SDR News)
  • Tech5 (John C. Dvorak)
  • CNET News Daily Podcast
  • This Week in Amateur Radio (TWIAR.org)
  • PC Mag Radio

So the only remaining ham radio ‘casts are Amateur Radio Newsline and TWIAR. AR Newsline is the old standby that I used to listen to on the local 2-Meter repeater, usually interesting and well done. TWIAR has some good content but it often tests my patience with drawn out introductions and weird sound effects. Keep the fast-forward button handy on that one. Slashdot Review sets the standard for “get to the point, say something interesting and move on.”  We need more shows like that. CNET News does pretty well, too.

Oh, I should mention Ham Radio Podclass, which I recommend to students studying to pass their next license exam.

I’ll toss in a couple of non-tech wildcards for you to consider:

  • WNYC’s Radiolab – “Science meets culture”, usually thought-provoking and well-executed
  • The Moth Podcast – People telling true stories without notes in front of a live audience
  • Common Sense with Dan Carlin – a fresh, logical approach to politics that generally annoys both Democrats and Republicans

So what are you listening to? Give me some fresh ideas.

73, Bob K0NR

This Spewed Out of the Internet #13

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0511-0701-3118-0930Things have gotten a little busy for me, so sorry about going dark on blog postings. I had several weeks of business travel, followed by a wonderful trip to the Caribbean. Unfortunately, no ham radio action on any of these trips.

As usual, K3NG has posted some interesting stuff on his blog. First, he commented on Amateur Radio Liberation Day, then he had a good post on The Problem of Closed Source and Proprietary Algorithm Modes.

The Fi-Ni report explained the mysterious reappearance of the 15 Meter band.

After pestering hams with announcements that the new ARRL web site is about to be turned on (drum roll please….), the League had to back off and announce that it just wasn’t quite ready yet. It would be a lot more effective to launch the web site, then promote it. That way, when people go to check it out, it is actually there.

The FCC decided that it would be a good idea to allow a remotely-controlled robot to use 430-448 MHz as a radio control link. These robots are intended to be used by law enforcement agencies to enter hazardous areas without endangering personnel. I guessed they missed the fact that the 70 cm ham band is home for thousands of FM repeaters in the U.S. This is yet another lame spectrum management decision by the commission. (See K3NG’s post on this topic.)

– 73, Bob K0NR

Results from the 2-Day Technician Class

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Radio MikeWe finished up the second and last day of our 2-day Ham Radio Technician License Class. The class ended with a VE test session, which was done by one of the local VE teams. We had 19 out of 21 students pass Element 2, qualifying them for a Technician Class License, for a 90% success rate. A handful of the students gave the General test a try and some passed that, too. We were very pleased with the level of interest in the class and the success rate on the exams.

Our learning objective was to have the students pass the Tech exam and know enough to be able to get on the air and operate a radio on the bands above 50 MHz.

The basic approach we used was to have two all-day classes, held on two consecutive Saturdays. We carefully developed a schedule that got us through all of the material and made sure we kept the class moving through it. We had originally looked at a one-day ham class but decided that was just too much material for one day. On the other hand, we did not want to go the traditional route of meeting once a week for 8 or more weeks. We didn’t think the instructors or the students would last that long! In the end, we chose an intense two-day approach, but made it clear to the students that they had to study the book in advance to be successful with this compressed approach.

We used the Gordon West Technician License guide, which is a very focused text, which ties the material directly to the exam questions. We also recommended the ARRL Ham Radio License Manual as another good reference book.  The ARRL book provides a broader context and includes material that is not required by the Technician exam.

One important point: I found this to be a very fun and motivating activity. It forced me to take a fresh look at amateur radio and really think about how to efficiently convey the material. Seeing a group of students get excited about ham radio gave me a spark of energy. Think about this if you are looking for some way to get re-energized in ham radio.

We have a waiting list for our next class, so it seems we need to do this again…soon.

73, Bob K0NR

Time to Change Part 97?

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when-all-else-fails-logoPart 97.113 has been the topic of much discussion lately, ever since the FCC communicated a rather narrow interpretation of the rules. See my previous post on this topic for more background information. From the ARRL web site, we find that the ARRL Board of Directors has chimed in:

The Board instructed the ARRL staff to seek a change in Section 97.113(a)(3) of the FCC rules to permit amateurs, on behalf of an employer, to participate in emergency preparedness and disaster drills that include Amateur operations.

This is not really a surprise and despite the usual criticism coming from some quarters, I am encouraged that the board sees this as an issue that requires action.

N5FLD lists the specific wording that the ARRL Board has approved, expressing some concern about the particular text chosen. I think we are clearly headed towards the standard FCC rule making process that will give everyone their say and, hopefully, we’ll arrive at a reasonable decision.

The February issue of CQ Magazine, arrived in the mail today, with a W2VU editorial taking on this topic. Rich points out that if you really want to get picky about it, ham radio publications are at risk due to a narrow interpretation of Part 97.113. For example, if an author is getting paid to review a new ham transceiver for publication in CQ, can he actually put it on the air without getting the foul flag thrown for “pecuniary interest”? So CQ wants to broaden the discussion, and has their own proposal for Part 97.113.

My read: stay tuned as we hash through this. There is enough support (based on good reasoning, I think) that this issue will get addressed. But it will take some time.

73, Bob K0NR


This Spewed Out of the Internet #12

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0511-0701-3118-0930Things have been busy around the K0NR household with Christmas, New Years, a general strategy of goofing off but having to go back to work in January.

Here’s a few things that have gotten my attention lately.

It seems that some of our pirate radio friends down in Texas think the FCC does not have jurisdiction over the Republic of Texas. See K3NG’s blog posting.

I came across Les N1LF’s blog: Big Iron: Chasing VUCC on Indoor Antennas. I am inspired by someone making the most of his station limitations and chasing VUCC anyway.

Wired Magazine reports that hearing loss is in decline even though we insist on shoving iPod and Walkman earbuds in our ears.

Then Wired publishes a totally lame article about increasing the intensity of a laser pointer. The most likely result is a toasted laser pointer.

The new Technician License question pool has been released and will take effect in July 2010. I took a quick look at it since I am involved in teaching a Tech License Class. It looks like some additional technical topics such as diodes, capacitors, inductors and decibels have been added to Element 2. Yes, that means the exam is probably more difficult than the current one.

The earthquake in Haiti is gaining lots of attention, inside and outside of the amateur radio community. Be sure to stay clear of the emergency nets and let these guys do what they can.

– 73, Bob K0NR

The Class is Full

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hamWow, the interest in the Ham Radio Technician License class has been intense! I was thinking we’d get 8 to 10 students. So far I’ve had over 30 people ask to be registered for the class but we had to cap it at 24. And some of our publicity efforts are just starting to kick in.

I also noticed this item from the ARRL Web Site:

2009 Sees Surge of New Amateur Radio Licensees

Don’t these people know that ham radio is an obsolete pastime for guys over 65 years old?

73, Bob K0NR

Circuit From the Past

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I was trying to provide some semblance of order in our basement, which is the storage area for my extensive collection of great radio and computer treasures (sometimes referred to as “junk”). I ended up wading through piles of stuff that I didn’t even know I had. It was like Christmas all over again!

I came across this little gem built into a RadioShack enclosure:

IMG_3348s

I guessed that it was a Code Practice Oscillator and that I must have built it some time ago. I had a vague recollection of the project. It certainly looked like something I might have built. There was a straight key in the same box that plugged right into the key jack.

I opened the inside and found this circuit board populated with through-hole parts. Replacing the 9V battery with a fresh one, the circuit came to life. A little action on the key and the sound of Morse Code filled the room.

IMG_3346s

I was curious about the design. There is one integrated circuit on the board but it was labeled only with a proprietary part number. What would I have used to built a code practice oscillator? Probably a good old 555 timer, so I pulled up an online datasheet for that part and got its pin out.

Then I started to do a some lite reverse engineering of the circuit and this partial schematic diagram appeared:

scan0003

The circuit is not complete — I just sketched out enough to confirm that the design was based on the 555 timer.  There is a lowpass RC filter on the 555 output to round out the square wave before it is fed to the speaker. It’s interesting that the key connects to the reset pin on the IC. I think this was to ensure a clean start up of the oscillator, to eliminate any frequency chirp.

So that’s a little diversion I had this weekend. Now back to cleaning out the basement.

73, Bob K0NR