Posts Tagged ‘repair’

Projects, projects, projects

December 11th, 2009

There are lots of projects going on here at the ranch and I’m not sure where to start. So, I’ll make a dreaded bullet list. A lot of this stuff has been a long time coming and I haven’t even had to spend much money on it, just time.

QSLing:

  • Some PJ2/K8GU cards are still in the queue since USPS didn’t like the “gift” (a laser-engraved poker chip) I was including with them—need to get padded envelopes.
  • No KP4/K8GU cards have been replied to since I don’t have a card design yet. This will be a photo card.
  • Plan to have all direct QSLing caught-up by the New Year.

HF station:

  • QRV on 80/40/20 with full SO2R.
  • Right TS-930S still needs a new set of MRF-485 drivers (although it puts out a few watts).
  • Left TS-930S needs PLL/master-oscillator alignment so it will go to bands other than 40 meters.
  • Built IK4AUY 2N5109 push-pull preamp from QEX article—needs finished and tested.  Have enough parts to build two, but might go with the simpler W7IUV design for the other instead.
  • Plan reduced-size K9AY for 80/40, maybe 160.
  • Plan W3NQN RX filters to go on the K9AY ahead of the preamp.

VHF/UHF station:

  • Wired in Jones plug(s) for the rotator.
  • 50-MHz transverter project is stalled awaiting parts orders (SM caps and toroids).
  • Do a planning cost analysis of 50- and 432-MHz transverter costs vs buying a used FT-817.
  • Ordered W1GHZ 903- and 1296-MHz boards and kits with W8ISS.
  • Plan PAs for 903- and 1296-MHz transverters.

Computers:

  • Bought new keyboards and mice for sakhalin and formosa.
  • Thanks to the generosity of a friend, sakhalin now has two Seagate Cheatah Ultra320 10-krpm 36-gB disks.
  • Added the old 1.7-gB IDE disk from the “ham computer” to sakhalin so I can still run TR.
  • Added the extra RS-232 ports from the “ham computer” to sakhalin for rig control.
  • In the process of configuring sakhalin to triple-boot Windows 95 (aka MS-DOS 7 for contesting TR), Windows XP (so I have it), and Xubuntu.
  • Plan to migrate formosa user data (not much of it) to sakhalin.
  • Plan to convert formosa from Xubuntu to OpenBSD using 20-gB drive from sakhalin, plus 120-gB already inside.
  • Plan to migrate crete server contents to formosa.
  • Plan to convert crete back from Ubuntu Server to “ham portable computer” running Windows 95 (aka DOS 7).
  • May run a network drop to the basement to use crete in the shop.
  • The MacBook (vieques) still just works.
  • So does the OpenWRT box (home).

And that’s just the hobby stuff!  Well, most of it.

Rebuilding and installing the CDE TR-2

October 3rd, 2009
CDE TR-2

CDE TR-2

Back in March, I had the opportunity to pick up a TS-700S for the cost of shipping it from Arizona to Illinois.  Since it’s an old radio with a built-in power supply, the shipping cost was significant, but $60 is a pretty good deal for a 2-meter all-mode radio. When we moved to Silver Spring, Maryland, I wanted to get on for the ARRL June VHF.  I built a 6-element WA5VJB “Cheap Yagi” using a pine firring strip for the boom and 1/8-inch aluminum rod for the elements.  I strapped this antenna to my DK9SQ mast with Ty-wraps and propped the radio up on moving boxes to make a few QSOs.

I stashed the antenna and radio until we visited my parents’ a few weeks ago.  While I was home, I retrieved a CDE TR-2 rotor that had been at my grandparents’ vacation home in Lakeside, OH, until they had the roof replaced and I acquired their old TV tower.  The TR-2 is the oldest of the CDE “bell rotors” and dates from the early to mid 1950’s.  It’s a certifiable antique!  I wired it up and plugged it in, only to discover that it was bound up.  But, the motor hummed.  So, I figured I had a chance.  About a week ago, I pulled it apart (over a plastic bin to collect the ball bearings that fell out) and degreased the whole thing.  I got the gears unbound and the shafts re-lubed and it worked like a charm.  I greased the bearings and put it back together.  Altogether, this was about an hour’s work—not too bad.  They don’t make things like they used to, that’s for sure.

I was unable to find the exact U-bolts for the lower mast mount; so, I fabricated my own from some threaded rod.  I put the rotor and antenna on a piece of fence top-rail and used ratcheting tie-downs to strap it to our chimney.  There’s nothing quite like listening to a local beacon (W3APL/B) fade into the nulls of your beam.  The multi-path is also pretty fascinating.  I’ll have to do some analysis of that.  Unfortunately, I haven’t been on the air for any tropo openings.  So, I may have to wait until January to enjoy it.

When I was in middle school and high school I would have been delighted to come up with a working 2-meter SSB/CW station for less than $100.  But, I suppose this is the advantage of time spent in the hobby.  The longer you’re in, the cheaper some aspects of it get because you have time to be exposed to good deals…  Anyhow, it sure was nice to do something dirty and mechanical after spending a lot of time in front of the computer at work.  I’m working on a 6-meter transverter next.

Resume of a Master Dumpster Diver: the Early Years

February 21st, 2009
Dumpster

Dumpster

With transition imminent in our lives, I have begun packing up some of my things that I don’t use much right now. It’ll save some time and headaches when we finally figure out where we’re going and begin the moving process. Coincidentally, my good friend Matt recently moved cross-country and elected to dispatch the majority of his tinkering resources via Craigslist. You see, Matt and I share a common vice: we are master dumpster divers.

I was reminded of this reality as I have been trying to center myself with respect to what’s important in life last week week. I have a lot of stuff, frankly, an embarassing amount of stuff. And, although I use a surprising amount of it, I really don’t need it. But, this post is about collecting the stuff, not getting rid of it. I’ll save that for a later post.

As I began sifting through some of the goodies tonight, a confluence of thoughts began to swirl in my head. I’ve had resumes and vitae on my mind for quite a few months now since I’ve been looking for employment (if you hire engineers or scientists, particularly for RF/signal processing/remote sensing/upper atmospheric/space research and development, I’m your man). And, I was poking through the rubble of my home “office,” which is actually my office, hamshack, and workshop, plus Sarah’s desk and books and the place that Sarah and I cram stuff into when company comes. Suddenly, it hit me: my entire resume can be read through my collection of odds and ends.

Dumpster diving, to borrow the analogy from Nelson Muntz, is like “kicking butt” in the sense that it might not involve any kicking at all. Likewise, you have to get to the stuff before it gets to the dumpster. This is the first rule of dumpster diving: Know who to ask, how to ask, and when to ask. The second rule is don’t get greedy. I learned both of these rules at a tender young age.

You see, the house I lived in between the ages of three and nine was next to the Village of Millersburg’s street department garage. Of course, this was a great boon for a child of my age to see all of the equipment and workers coming and going. Mom and Dad may remember this story differently; but, this is my recollection.

Although I was fascinated by all aspects of construction work, the one thing that I obsessed over more than anything else was signage. Some kids are experts on dinosaurs, I was fascinated by road signs. I coveted the road sign poster on the wall at the BMV. Mom had inquired about obtaining one for me to no avail. The other thing I coveted was a road sign or two of my own. A friend had a stop sign in his room; but, I was looking for something more exotic, maybe a yield sign. My poor mother worked some connection she had at the Street Department to get a discarded sign. She told me that we could go down to the sign depot and pick one out in the morning, which was probably a mistake.

I rose particularly early the next morning and, after locating the sign depot, collected a few signs for myself. When you’re a kid, street signs don’t look big and heavy on their posts. But, when you get up close, they rival your personal geometry. So, I left a trail of signs I couldn’t carry back up to the house. I don’t remember the details of what happened next, other than that we had to return all of the signs and get “approved” ones. I hope somebody thought it was funny; goodness knows I learned a lesson that day about the difference between dumpster diving and theft of city property.

A few years later, Mom had an antique dealer come through the barn behind the house and the signs caught his eye. She let him have them for a song. I was incensed at the time, although in retrospect, it was probably better to not profit too much on them.

The basement of the Inventor’s Hall of Fame once hosted an area where kids could dismantle old hardware. We were fortunate to visit when some racks of AT&T Long Lines hardware had been recently donated. I think I carried a half-dozen plastic sacks of relays, waveguide, transistors, meters, and other assemblies out of there that day. Although I have sifted through most of that by now, the juiciest pieces still remain in my inventory, ready for use. I still don’t think that the docents knew what hit them when the budding master dumpster diver rolled in.

Although I dabbled off and on in the barter of used electronics and such in high school, the dumpster diving began in earnest again in college, where I met guys who weren’t afraid to actually climb into real dumpsters to fish things out. Those were good times. Most of the stuff we pulled out of the dumpsters was building materials, which we used to spruce up our living spaces. Blocks from a demolished (the Young Building of Philosophy and Relgion, a grievous sin against architecture and HVAC) academic building allowed us to put an “upper deck” couch behind the regular couch in our apartment for stadium seating. This was great for watching movies, or at least watching my roommates play Mario Kart 64 with their pharmacy notes on their laps…right.

One of the other great successes was DuddiNet and the Tower of Power. I dragged an 8-foot relay rack (rescued from the scrap heap at a summer job) into my dorm room and filled it full of computers and networking equipment. I asked the university IT people if they had any leftover rolls of CAT5 cable and they gave me as much as I wanted. We pulled our own network in the dorm. At that time, the dorms were 10baseT with hubs. So, it was a real bottleneck if you wanted to move some data (use your imagination here) around. We put in a private switched 100baseT network that connected four rooms on two floors.

In more recent years, I’ve scored some terrific stuff just by paying attention when spaces are being cleaned-up. For instance, that’s how I got my HP vector voltmeter and my oscilloscope. And, indirectly, through Dad, it’s how I got some more Greenlee punches and a set of metal-marking stamps. Anyhow, in order to protect “sources and methods,” I’ll decline from disclosing too many details about my more recent activities…I haven’t swiped anything from a forbidden dumpster, though. Promise.

» Read more: Resume of a Master Dumpster Diver: the Early Years

Miscellaneous

October 27th, 2008

Just some miscellaneous news from happenings over the past month…first, the good news…

I passed the oral exam on Tuesday.  So, I’m officially ABD now.  There is a light at the end of the tunnel.

Nikon released the 50mm f/1.4G AF-S SWM prime lens at the end of September.  I guess I wasn’t paying close enough attention.  This is good news for D40 owners such as myself.  But, the price is almost as steep as the Sigma f/1.4 30mm and 50mm HSM lenses.  The 30mm lens would be a better all-around choice.  Perhaps Nikon will come out with something a little shorter by the time I’m ready to buy.  Until then, I’ll keep using the 50mm f/1.4 AF-D that I have on indefinite loan from work.

I managed to destroy the drivers in my recently-repaired TS-930S.  I considered swapping the drivers from my second radio into this one.  But, when I took that radio apart, I found that the capacitors had swollen.  So, I have parts on order to fix that.  UPS says they’ll be here today.  I requested a quote for the NTE236 replacement for the MRF-485 drivers.  They want almost as much for the NTE236 as RF Parts does for the MRF-485.  I think I’ll get the MRF-485s.

We had high winds yesterday (Sunday).  I lost the 80-, 40-, and 20-meter dipoles.  Sarah said, “Do you expect that (80-meter) antenna to last the winter?  It just broke in September.”  She’s right.  I’m not sure I’ll repair it if it breaks again.   It’s less than a week to the CW Sweepstakes and I only have one working radio (FT-840) and antennas for 10 and 15 meters.  The forecast calls for 65 and sunny on Thursday.  So, I’ll probably take the day to work on antennas.

» Read more: Miscellaneous

TS-930 update

October 9th, 2008
TS-930S AVR board

TS-930S AVR board

Thanks to KA5IPF and WE0H, who answered my query on the TS-930S reflector!  The oscillation was due to dried-out electrolytic capacitors on the AVR board and unhappy pass transistors on the heatsink in the back.  I bought 105 C capacitors instead of the 85 C ones that Kenwood used, plus bumped the voltage rating up to 63 V instead of 50 and 35.  Fortunately, I still had some leftover 2N5886’s, but I need to buy a replacement set of capacitors and pass transistors to have on hand in case the other radio fails.  I haven’t tested it in contest conditions, but all signs are good that we should be ok.  Maybe the NS tonight?

Have a Synton ARC (sorry about the ancient web site…we are going to fix it…sometime) meeting at 2:00 today.  Everybody else in the Club is building SoftRocks.  I’m bringing my IK4AUY preamp parts to start building.  Need to order some PL-259’s, probably today.  Yeah, and I need to finish writing my prelim exam document and presentation.  So much to do.  So little time.

» Read more: TS-930 update

TS-930S power supply

September 28th, 2008
Benched TS-930S

Benched TS-930S

Remember how I said that I thought the W9RE switchbox had terrible isolation?  Well, although I didn’t measure it with a VNA, I was doing some testing the other day and noticed that it only seemed only bad when the left radio was transmitting.  For example, I put the left radio on 40 meters and the right radio on 20 meters.  There was terrible broadband hash whenever I closed the PTT line on the left radio.  So, I put the right radio on 40 and the left radio on 20 and transmitted again on 40.  No hash, just some faint trash that followed the keying.

I had noticed during the Sprint that the vacuum fluorescent display on the left radio was flickering following the keying.  But, I didn’t give it much thought until now.  I flicked the meter selection switch to Vc and sure enough, it was too high (>28 volts) on transmit.  Plus, it would spike and pin the meter whenever I released the key.

Today, I built a band decoder cable (fortunately, I had stocked-up on the mini-DIN plugs and the PIEXX board uses Yaesu BCD format) for the Yaesu FT-840 and put it into the left radio position. It’s clean, too.
The left ‘930 is now on my workbench, which is barely large enough for it.  It turns out that there is a substantial (4 volts peak-to-peak) ripple on the power supply when I close the PTT.  I sent a note to the TS-930S reflector; but, unless KA5IPF answers it, I’m probably on my own.  I suspect it’s just going to be a matter of disconnecting subsystems until I find the offender.

Until then, I’ll be using the FT-840 and the old TS-930 for SO2R.  But, at least I’ll be able to hear!  I’m also relieved that I probably won’t need to rewire W9RE’s switchbox.  I just need to build some short jumpers and W3NQN filters for all bands.

» Read more: TS-930S power supply

Station work

September 20th, 2008

A couple of shots with the ole Wrist Rocket and some creativity with the DK9SQ mast got a new line into the tree.  I’ll be back on 80 again soon!  I’m still trying to figure out what to do with the 6×2 switching system.  I found two relays in my junk box.  But, I need four more, plus a clue about how to wire it all up.  I want to rebuild it as a system like Top Ten Devices suggests.

I also picked up a dead, but cosmetically pleasing, 19-inch Dell flat panel from the scrap pile at work on Friday.  This afternoon, I tore it apart and put it back together.  It works now.  For my good conscience, I’ll be taking it back to work on Monday.  Rats.  I was hoping I’d at least have to solder something…

» Read more: Station work

Antenna Work

July 10th, 2008

remote-box-bw-web.jpg

I mentioned a few weeks (months?) ago that I was working on some antenna upgrades and that I had a 20-meter Moxon up.  Well, I built the Moxon out of #14 THHN, which has PVC insulation, using dimensions for bare wire.  Oops.  (This could easily have been a life lesson:  read the fine print.)  I decided against rebuilding the Moxon for two reasons:  First, it was a pain to install in the trees.  Second, I can get a dipole up higher.  So, I put up a 20-meter dipole yesterday.  One end is at about 40 feet and the other at 35 feet or so.  SWR is good and A/B tests on receive are good.  Looking forward to trying it out in the NS tonight.

I also pulled the 80/160 matching network (see picture) off of the roof and moved it to the ground.  This is a major improvement for repairs and adjustments and I gain an extra 10-12 feet of radiator on 160 when I short the feeder.  Since it’s now on the ground, I won’t actually get to try it out on 160 until the mowing guy quits for the year.  N3OX tells me that he solved the “squeemish about wires in the grass” problem by offering to mow his own yard.  We travel too much and I’m really not willing to let the landlady off the hook on anything.  So, no 160 during the summer is the price I have to pay.  I also rebuilt the box with a much more intelligent layout than before.  Let’s just say that I couldn’t bring myself to post the old one on the Internet with my name on it.

I’ll probably try to add 10 and 15 to the 20-meter dipole, just to have them.  But, that’s “later” project.  I also need to build the W3NQN filters for those bands still, too.  I have all of the parts (even the boards) for KK1L‘s 2×6 switch.  But, I’ve cooled off on building it.  Some day.  Maybe.

IARU HF World Championship is this weekend.  This had been one of my favorite contests.  I’ve hardly participated in it since 2004, when I operated W0AIH SOLP CW.  I’m just not much of a single op DX contester these days.  Sarah probably is a big part of that.  She doesn’t like when I contest much longer than the Sprint at a stretch!  We need to work on that.  I’m trying to operate fewer contests more intensely.  SS CW and the CW Sprints are the ones I’m focusing on.  I’ll probably make some Q’s in the IARU, even if it’s just working W1AW/9 and NU1AW/0.

Keep on Flying: A Life Lesson from R/C

July 6th, 2008

airplane-web-bw.jpg

I’ve written several times about the airplane.  So, this story will repeat somewhat.  As a child, I was interested in R/C airplanes.  In a rare lapse of judgement, Dad bought a used “trainer” from a coworker.  However, since we’d been told that crashing is inevitable, he sold it.

Crashes are inevitable in R/C.  The only way to get better is to keep flying, keep crashing, and keep repairing.  Although most things in life are more robust than R/C airplanes, the ability to pick up the pieces and devise creative solutions after repeated setbacks is a valuable skill.

Antenna work, completed and coming

May 8th, 2008

PL-259

I took K9BF’s TA-33jr down a few weeks ago because it didn’t look too secure and I wasn’t able to get it up high enough to play well on 20. I had entertained the thought of building an East/West-firing lazy-H array to replace it. But, that would have required me to move my high 40-meter dipole, probably the best antenna I’ve ever had for that band. I decided instead to build a Moxon, which seemed to be a fitting tribute to W4RNL, who recently became an SK.  The Moxon has about the same gain (albeit in one direction) over ground as the lazy-H and a little fatter beam.  It’s not yet operational; but, I’m working on it.

The 160-meter matching portion of the 80-meter dipole needs to be adjusted and repaired.  I didn’t use big enough RF chokes in the switching network and they got burnt.

I might do something to the southeast if I like the performance of the Moxon, too.  Hopefully, the beams will give me the edge I need to make some more QSOs on 20 in the Sprint and SS this Fall.

Grad school is really sapping my energy.  We’ve been on the road a lot and the end is not yet in sight!  Plus, there’s real work to be done, too.