Here comes our fourth 'Barn Door' CLE. Between us there will be a great variety of different receiver types in use.
 
    Days:      Friday 22 to Monday 25 July 2016
    Times:    Start at  ## 11 a.m. on Friday, your LOCAL time
                  End at   ## 3 p.m. on Monday, your LOCAL time
    Frequencies:   Centred on 360 kHz (see below)
    NDBs:     NOT MORE than 100 'normal' NDBs including any UNIDs
                  (That is not intended to be a target to reach)
 
We are all asked to listen with NON-SELECTIVE receivers - i.e. with a WIDE filter or NO filter.  Your 'barn door' should be open wide so you could hear, at the same time, any NDBs 2 kHz away on both sides of your receiver setting - E.g. NDBs on 348, 349, 350, 351 and 352 kHz with the receiver set to 350 kHz.
 
You could listen with:
 
1. A simple home-made receiver, such as a single transistor set with regen. (e.g. based on the sets used by Mike, Finbar and others).
 
2. OR - an Ultralight receiver, maybe one converted to cover the NDB frequencies with a modified aerial.
 
3. OR - an 'antique' receiver (e.g. Eddystone, R1155, Scott, etc.)
    Perhaps you have something you've not switched on for many years?
 
4. OR - a normal receiver but with NO filtering, or using a WIDE FILTER,
    (not less than about 2 kHz and no selection of an audio filter).
 
You choose how wide a RANGE of frequencies you will listen in, CENTRED ON 360 kHz.  You could choose 350-370 kHz or 330-390 kHz or 260-460 kHz, etc.
   (This allows each of us to choose a +/- range with enough NDBs to
   match our equipment's capability.  It will also allow our loggings to
   be compared in the Combined Results, at least around 360 kHz).
 
Logs should show NOT MORE THAN 100 NDBs please (if more than 100, the harvester program will 'drop' the loggings furthest from 360 kHz).
 
There is a big range of possible extra targets you could set yourself - maybe the wide bandwidth, the centre frequency of 360 kHz and the 100 loggings limit do not challenge you enough!
You could listen only in daytime and/or away from home.
Or how about NDBs on 360 +/- 10 kHz or even +/- 5 kHz?
The Twente remote receiver in Holland could be interesting to use for the whole of your (only) CLE log.
(Go to http://websdr.ewi.utwente.nl:8901/ and read the advice.
Select AM and 'MAX IN', enter e.g. 354.7 in the frequency box and drag
the filter's limits to 2 or 3 kHz from the centre frequency on both sides).
 
I will summarise everyone's equipment on the first page of the combined results, so please describe:
The RECEIVER/AERIAL you used and the FILTER(s) selected, if any.
  (If homebrew, please quote the total number of active devices used,
   the transistor/valve types, whether using regen., etc.)
 
All the usual procedures for making logs apply:
 
Send your CLE log to the List, if possible as a plain text email
and not in an attachment, with CLE209 at the start of its title.
 
Please show on EVERY LINE of your log:
    # The full date (or Day No.) and UTC (the day changes at 00:00 UTC).
    # kHz - the beacon's nominal published frequency, if known.
    # The Call Ident.
 
Show those main items FIRST on each line, before other optional details such as Location, Distance, etc.   If you send incomplete  
logs to the List during the event, please also send your 'Final',  
complete one.
 
Whether you are a first time CLE-er or a regular, make your log interesting to everyone by showing your own location with your equipment details.
Feel free to share any comments you have on this unusual event.
 
## The extra daytime hours on the first and the last day might help some of us planning to listen out of doors.
 
I will send the usual 'Any More Logs?' email at about 17:00 UTC on Tuesday so that you can check that your log has been found OK.    
Make sure your log has arrived on the List at the very latest by  
08:00 UTC on Wednesday 27 July.   I'll try to complete making the combined results on that day.
 
However you choose to take part, I hope you will find your 'back to basics' listening enjoyable and worthwhile.
 
     Brian
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From:   Brian Keyte  G3SIA          ndbcle'at'gmail.com
Location: Surrey, SE England         (CLE co-ordinator)
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P.S.   NOT FOR YOU?
 
Listening without narrow filters is not going to revolutionise our hobby!
But there ARE some unexpected benefits and advantages:
 
1. Hearing several beacons on a few adjacent frequencies at the same time becomes easier as you get practice at recognising them by listening to their very different audio tones. At first, when listening to a random frequency setting, you may hear just one or two beacons. But after listening for a lift le while you realise that there are three - - four, maybe a lot more, all of them audible without altering any of the receiver controls.
It is a skill that gives satisfaction as you improve.
 
2. Hearing multiple beacons like that can be useful because, with no extra tools, you can hear NDBs over a wide frequency range much  
more quickly than usual, perhaps spotting the arrival of new UNIDs  
or the return of occasional beacons.  (To protect your hearing, keep  
your receiver gain controls fairly low, except on very quiet frequencies).
 
3. With normal listening it is easy to miss any NDBs that have abnormal carrier frequencies or non-standard offsets.  With 'Barn  
Door' listening they won't escape because everything is let through.
 
4. When using a wide filter, you may be surprised by hearing several
Broadcast Station signals (e.g. harmonics) among the NDBs and you will be able to identify them.
With a narrow filter, often you may not recognise an AM signal as audio
- it just sounds like nondescript 'hash' affecting a wide range of
frequencies around the central carrier.
 
Maybe listeners will report some other good things about their barn door listening during the CLE - and probably some bad things too!
 
Do join in if you can.
 
Sent from my Hudl