Saturday, 9 February 2019

Mr. Carlson's Lab - A YouTube Treasure

This blogspot was originally published in June 2015.

**********

I recently watched two superb YouTube videos. The first described exactly how to determine the 'shielded' side of a fixed capacitor and the importance of knowing this information.

As you have probably noticed, most modern fixed capacitors no longer indicate the 'grounded' end or the lead going to the internal shielding. At one time, the capacitor's polarity was commonly marked with a band on one end but this is no longer the case ... even though one side is indeed still the shielded side. Depending on exactly what part of the circuit your fixed capacitor is being used in, connecting it in the reverse direction (shield going to signal side), can introduce hum, RF pickup, instability and generally result in poorer capacitor / circuit performance ... and all it takes to determine which lead is which is an oscilloscope!


The second video I viewed shows the process used to resurrect a Yaesu FT-1000MP in truly terrible condition. In a very professional step-by-step process the video shows the logical and systematic approach at making the radio better than new.


Both videos are done by a truly gifted engineer, Paul Carlson, VE7ZWZ, and are exceptionally well done ... the quality one would expect to have to pay for rather than freely view on YouTube.

If you visit Paul's YouTube channel, you'll find a host of other radio and audio-related videos and I guarantee that you will learn something of value ... and probably hang around to watch several more. They are really well done.

Wednesday, 30 January 2019

CLE240 Results

courtesy: NOAA


Last weekend’s CLE240 saw mediocre propagation for North America and European listeners alike.





It seems that our monthly CLE schedule continues to be synced with the Sun’s monthly rotational period that has been regularly lining us up with the same massive coronal hole, elevating earth-directed solar wind speeds now for several months.

Several CLE participants in the USA commented on the lack of any propagation into BC, further fueling my long-held belief that BC seems particularly sensitive to any geomagnetic activity in the auroral zone to our north. The auroral activity always seems to dip further to the south here for some anomalous reason, as listeners just a few hundred miles to the south or southeast see far less absorption than is observed here.

With a few exceptions, the main effect of these conditions is to largely kill the normal east-west propagation path and just allow single-hop signals from the south or the SE/NW to dominate. Typically, the path to the Pacific is not affected and can often be enhanced.

As a side observation, this past weekend was also the CQWW 160m DX contest and, as one left-coaster commented, conditions were the “worst seen in 10 years”. One would expect to see much better conditions and a much quieter Sun at this point in the solar cycle!

With fingers crossed for better propagation during the next CLE, here is what was logged over the three-night listening event from my location here in BC’s Southern Gulf Islands using a Perseus SDR and an Inverted-L antenna resonated to 400 kHz:

26 05:00  385     QV            Yorkton, SK, CAN
26 07:00  385     OCC         Yakutat, ALS
26 09:00  385     MR           Pacific Grove, CA, USA
26 09:00  385     EHM         Cape Newenham, ALS
27 07:00  385     CPZ          Chaparrosa Ranch, TX, USA
26 07:00  386     SYF           St. Francis, KS, USA
26 09:00  386     HAU         Helena, MT, USA
26 06:00  388     OK           Preston, OK, USA
26 07:00  388     MM          Fort Mc Murray, AB, CAN
26 07:00  388     JW           Pigeon, AB, CAN
26 06:00  388     CDX         Somerset, KY, USA
26 06:00  389     YWB         Kelowna, BC, CAN
26 04:00  389     TW           Twin Falls, ID, USA
26 07:00  389     CSB          Cambridge, NE, USA
26 07:00  390     HBT          Sand Point, ALS
26 11:00  390     AES          Northway, ALS
26 04:00  391     TK            Telkwa, BC, CAN
26 11:00  391     GXD          Nacogdoches, TX, USA
26 07:00  391     EEF           Sisters Island, ALS
26 06:00  391     DDP          Dorado, PTR
26 09:00  392     ZFN           Tulita, NT, CAN
26 05:00  392     PNA           Wenz, WY, USA
26 05:00  392     ML            Charlevoix, QC, CAN
26 08:00  392     FMZ          Fairmont, NE, USA
26 10:00  393     UKS           Kosrae, FSM
26 04:00  394     RWO         Kodiak, ALS
26 07:00  394     DQ            Dawson Creek, BC, CAN
26 07:00  395     YL             Lynn Lake, MB, CAN
26 04:00  395     ULS           Ulysses, KS, USA
26 07:00  395     5V             Drumheller, AB, CAN
26 07:00  396     YPH           Inukjuak, QC, CAN
26 05:00  396     CRS          Corsicana, TX, USA
26 05:00  396     CMJ          Ketchikan, ALS
26 07:00  397     ZSS            Saskatoon, SK, CAN
27 12:00  397     SB             San Bernardino, CA, USA
26 10:00  398     YOD         Cold Lake, AB, CAN
26 06:00  398     3D            Cumberland House, SK, CAN
26 11:00  399     ZHD         Dryden, ON, CAN
26 11:00  399     SRI           Pribilof, ALS


A summary of results for all participants can be found here, at the ndblist info site.

Saturday, 19 January 2019

Hunting For NDBs In CLE240

OO-391kHz - Oshawa, Ontario courtesy: VE3GOP




This coming weekend will see another monthly CLE challenge. This time the hunting grounds will be 385.0 - 399.9 kHz.

 


For those unfamiliar with this monthly activity, a 'CLE' is a 'Co-ordinated Listening Event', as NDB DXers around the world focus their listening time on one small slice of the NDB spectrum.

A wonderful challenge for listeners in North America is to hear little OO - 391kHz, located in Oshawa, Ontario. It puts out only 7 1/2 watts but has been logged on both coasts as well as in Europe! Listen for its USB CW identifier (with your receiver in the CW mode) on 391.396 and its LSB ID on 390.595 kHz.

MF propagation this past week has been good and signals in this frequency range should be propagating well if things stay undisturbed for the weekend. As usual however, a large coronal hole has returned to its monthly CLE position and its weekend effects are still unknown.

When tuning for NDBs, put your receiver in the CW mode and listen for the NDB's CW identifier, repeated every few seconds. Listen for U.S. NDB identifiers approximately 1 kHz higher or lower than the published transmitted frequency since these beacons are modulated with a 1020Hz tone approximately.

For example, 'AA' near Fargo, ND, transmits on 365 kHz and its upper sideband CW identifier is tuned at 366.025 kHz while its lower sideband CW ident can be tuned at 363.946 kHz. Its USB tone is actually 1025 Hz while its LSB tone is 1054 Hz.

Often, one sideband will be much stronger than the other so if you don't hear the first one, try listening on the other sideband.

Canadian NDBs normally have an USB tone only, usually very close to 400 Hz. They also have a long dash (keydown) following the CW identifier.

All NDBs heard in North America will be listed in the RNA database (updated daily) while those heard in Europe may be found in the REU database. Beacons heard outside of these regions will be found in the RWW database.


From CLE organizer Brian Keyte, G3SIA, come details via the The NDB List Group:


Hello all,

Our 240th Coordinated Listening Event is less than a week away.
We can now forget all about pyramids and relax with a straightforward
event.   Whether you are a keen propagation watcher or just a
take-what-comes listener, please join in.

    Days:    Friday 25 January - Monday 28 January
    Times:   Start and end at midday, your LOCAL TIME
    Range:   385.0 - 399.9 kHz

Please log all the NDBs you can identify that are listed in that range
(it includes 385 kHz but not 400 kHz) plus any UNIDs you find there.
We last used this frequency range for CLE224 in October 2017.


Please send your final log to the List (no attachments and ideally
in a plain text email) with ‘FINAL CLE240’ in its title.
Show on each line:

    #   The Date (e.g.  '2019-01-26' etc.  or just '26' )
    #   The Time in UTC (the day changes at 00:00 UTC).
    #   kHz  - the nominal published frequency, if known.
    #   The Call Ident.

Please show those main items FIRST.  Other optional details such
as Location and Distance go LATER in the same line.
As always, of course, tell us your own location and brief details
of the equipment that you were using during the Event.

We will send the usual 'Any More Logs?' email at about 18:00 UTC
on Tuesday so that you can check that your log has been found OK.

The combined results should then be completed within a day or two.

You can soon find full details about current and past CLEs from the CLE page
http://www.ndblist.info/cle.htm  It includes access to CLE240 seeklists
for your part of the World, prepared from the previous loggings in Rxx.

Good listening - enjoy the CLE.
      Brian and Joachim
---------------------------------------------------------------
From:      Brian Keyte G3SIA      ndbcle'at'gmail.com
Location:  Surrey,  SE England     (CLE coordinator)
---------------------------------------------------------------

  (If you would like to listen remotely  you could use any one remote
  receiver for your loggings, stating its location and owner and with their
  permission if required.  A remote listener may NOT also use another
  receiver, local or remote, to make further loggings for the same CLE)


These listening events serve several purposes. They:
  • determine, worldwide, which beacons are actually in service and on-the-air so the online database can be kept up-to-date
  • determine, worldwide, which beacons are out-of-service or have gone silent since the last CLE covering this range
  • will indicate the state of propagation conditions at the various participant locations
  • will give you an indication of how well your LF/MF receiving system is working
  • give participants a fun yet challenging activity to keep their listening skills honed
Final details can be found at the NDB List website, and worldwide results, for every participant, will be posted there a few days after the event.


The NDB List Group is a great place to learn more about the 'Art of NDB DXing' or to meet other listeners in your region. There is a lot of good information available there and new members are always very welcome. As well, you can follow the results of other CLE participants from night to night as propagation is always an active topic of discussion.

You need not be an NDB List member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers. 

Remember - 'First-time' logs are always VERY welcome!

Reports may be sent to the NDB List Group or e-mailed to CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above. If you are a member of the group, all final results will also be e-mailed and posted there.

Please ... give the CLE a try ... then let us know what NDB's can be heard from your location! Your report can then be added to the worldwide database to help keep it up-to-date.

Have fun and good hunting!

Friday, 11 January 2019

The 2019 Winter "Classic Exchange"

W7OS - Radio Club of Tacoma working the CX
This winter's running of the CW "Classic Exchange" will take place on Sunday, January 13 and on Tuesday, January 15. The following month will see the Phone "Classic Exchange", on Sunday, February 24 and on Tuesday, February 26.


The "CX" encourages participants to use older vintage gear including any homebrew equipment, both receivers and transmitters. A unique scoring system provides bonus points for various equipment and combinations as well as encouraging 'repeat contacts' when you switch to different equipment.


W8KM and his wonderful vintage station

No vintage gear? ... no problem! All amateurs are invited to participate and get in on the fun no matter what they are using and submit their scores.


K3MD's Heathkit AT-1 and Hallicrafters HT-37 ready for the CX

The CX is a low-key relaxing affair and the 'extra' Tuesday operating period should encourage a lot of midweek activity from the vast numbers of retired operators who cherish and run older gear.


Lots of combos ready at W4BOH's CX setup


























K6ZI, Las Vegas - WWII ARC-5s ready to go

A summary of the Fall 2018 CX and soapbox comments, along with some wonderful vintage-station eye candy, may be found here.

For complete details of the upcoming event, see the web site announcement here.

If you've never entered the Classic Exchange, why not give it a try this year as it truly is a case of 'the more the merrier' ... and eastern operators, make sure to keep the porch light on for those out west!

Wednesday, 2 January 2019

Radio Bench Fun!




Every once in awhile I’m reminded of the magic of radio and why this hobby is so much fun!

For the past week and a bit, in between power outages of up to four days, I’ve been optimizing a circuit from the December ‘36 ‘Radio’ magazine.





It looked like it might be something that would be fun to use during the weeknight NRN (Novice Rig Nights) activities ... a Jone’s-style push-pull crystal power oscillator using a pair of 6V6s. The original article called for 6L6s but my power supply can probably not provide much more power than is already coming from the 6V6s and these will likely be easier on my few precious novice-band crystals.





The circuit is lashed-up on my very well-worn 'aluminum breadboard', which is peppered with numerous convenient holes punched or drilled for mounting various crystal sockets, tube / coil sockets, variable caps etc ... it really looks awful but allows easy parts swapping to test out different configurations.



This afternoon I had the thing perking to my satisfaction, along with a very sweet-sounding CW note, using my WWII - era 7121kc crystal. Everything looked good into the dummy load so I connected the 40m antenna through the tuner, clipped the bug to the cathode resistor and at about 40 minutes before sunset, sent a short ‘CQ’, hoping for a nearby local but not really expecting a reply ... now this is the magic part. 

My CQ was immediately pounced-upon by John, N2BE, on the other side of the continent, in New Jersey! I shook my head at the dangling pile of clip leads and just-barely soldered components clamped in the bench vice and had to smile when he gave me a 589 report! John was working the AWA's Linc Cundall CW Contest, where rigs must be pre-1950 designs or builds. I was happily able to give him a legitimate point, using my 1936 Jones oscillator!



At 400V on the plates,  the little lash-up puts out 18 watts and seems to be about 45% efficient ... not too bad for a power oscillator. As well, the crystal current must be low as it keys nicely and doesn't sound stressed. 

I’ll soon be rebuilding the little transmitter into something more presentable, probably similar to my Tri-Tet-Ten, using the short-lived but visually attractive mid-30’s building style that mated a shiny aluminum plate to a nice wooden base.


Stay tuned ... I’ll hopefully have it completed over the next few weeks and will be looking for some 80 / 40m  NRN Monday night fun!