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IARU Grid
Square IO82VO * WAB Square SO89 *
CQ Zone 14 * ITU Zone 27 * 52:35:48N 2:12:16W * 125m a.s.l.
MØMTJ - Operating Conditions
Originally my 'shack' was located in the spare
bedroom, but in 2011 it was moved and re-established in the much
smaller box room so that the spare bedroom could be used as a proper
guest room without all my associated electronic clutter!
I now share the tiny box room with a wardrobe, vacuum cleaner and most
importantly the iron and ironing board! So I now squeeze into a space
that I think of as "Ronnie Corbett's Corner". Here it is:
The shack in October 2011 - Click the images to enlarge the photograph
The shack in January 2012
Click the images to enlarge the photograph
MØMTJ Amateur Radio Station: My
amateur radio station consists of an Icom IC-706MKIIG Transceiver with
FL-223 (1.9 kHz) and FL-232 (350 Hz) filters. The 706 is used as a home
base radio for HF, 2 metres and 70cm SSB. Also sitting proudly on the
shelf is a Kenwood TS-590S transceiver for HF and 6 metres. For FM work
on 2 metres and 70cms I have a Yaesu FT-7900. I also have a lovely
little Yaesu
FT-857D which I sometimes use for mobile work and 2 metres and 70cms at
home. It also has a narrow INRAD 2.0 KHz 8-pole Collins
filter installed for SSB work which improves reception on
crowded
bands - this narrow filter also helps increase the
audibility of transmitted audio under difficult conditions, when
selected for TX in the menu. http://www.inrad.net
Microphones:
I use the standard HM103 microphone that was supplied with the Icom IC-706mk2g which I
find perfectly good. The same goes for the MH48 microphone supplied with the
Yaesu FT-7900 which also seems perfectly adequate. The same cannot be
said for the supplied microphone that is supplied with the Kenwood TS-590.
While the audio quality of the Kenwood microphone is excellent, the
microphone casing is very 'creaky' and unless one holds it very gently,
it produces a lot of creaky noises on air. I tried tightening the case
and also placing sponge and other soft materials inside the case, but
to no avail. I am currently experimenting with an old Radio Shack /
Tandy Optimus 33-7058 unidirectional dynamic microphone mounted on a
goose-neck. PTT being achieved by a hand switch or a foot switch. More information here >
Aerials: For the HF bands there is an
Inverted L aerial
trapped for 40 metres and 80 metres with the addition of a 17 metre
band section and adapted for use on Top Band by the use of a switchable
loading coil. This is fed by RG213 coaxial cable.
There is also a choice of a trapped dipole for 20 and 10 metres fed
by 75 ohm twin
feeder and 1:1 balun to the ATU or 7.2 metre high "UnTenna" supported
by a fibreglass fishing pole using a top quality G Whip
9:1 UnUn, or a
20 meter ground plane antenna again supported by the fibreglass fishing
pole. All fed via RG213 coaxial cable. There is also a 10m / 6m
resonant wire dipole located in the loft space. The antennas are
switched in the
shack for easy
selection and are fed via either and MFJ
945-E, LDG Z11Pro or AT200ProII Antenna Matching Units.
VHF & UHF: 2m & 70cms FM are taken care of by either a Watson W50 'white stick' dual
band vertical collinear or a dual band wire J-Pole antenna. SSB is catered for with a DK7ZB design dual band Yagi antenna, with 5 elements for 2 metres
and 8 elements for 70cms, mounted horizontally and rotated by a lightweight AR300 rotator.
Computer Data Interfaces: There
is a
SignaLink
external USB sound card that links the Icom transceiver to a Windows PC
for use with data modes such as CW (Morse), RTTY, PSK31, SSTV and
Packet etc.
The
Kenwood TS-590S is also linked to the PC by direct USB connection which
conveniently allows data RX & TX and rig control.
Computer: I had to rebuilt the PC in January 2012: The Abit
Motherboard that I installed in August 2008 disappointingly failed
prematurely in December 2011.
Now the PC consists of a new Gigabyte
GA-M68MT-S2P AM3 ATX motherboard (with solid long life capacitors), AMD
Athlon II X2 250 3.0GHz Dual Core Processor, 2GB Corsair DDR3 1333MHz
RAM Memory and a Seagate 500GB Sata III Hard Disk Drive. The existing
components used are the original Nokia style case (from 2001), a Hiper brand HPU4S425 Silent 425
Watt PSU (from 2008), a Card Reader and a DVD Writer.
The system runs Windows XP SP3. All supplied by CCL
Computers. http://www.cclonline.com
I have found from experience that the switch mode power supplies that
come with many of the cheaper PC cases and towers can create rather a
lot of RF noise across all bands. I have used the 'Hiper' brand of ATX
PSU's previously and found them to be fairly quiet as far as RF QRM is
concerned. QRM
Software: I Use Ham Radio Deluxe v5.0 for logging together with eqsl for QSLing;
Digital Master 780 for data; FTBasic and FT7900 for memory management.
I also use RadioMobile for pixel plotting.
I do also have a Morse key (of
course!),
but I have yet to learn this art - though I am very keen to do so at
some point.
Speakers: ' I
have a choice of several
external loudspeakers; A couple of old 'Realistic' Minimus 3.5 Tandy brand
speakers which are excellent. I use one for the Icon IC-706mk2g and the other for the Kenwood TS-590s. There is also a
little 'CRT' brand MS120 mobile speaker connected to the Yaesu FT-7900 and although it is
small it is quite clear and because it cuts out a lot of low frequency
sounds it can be very helpful in improving intelligibility in some
circumstances - it's not used full time but handy to have.
For
'bigger sound' I also have a large speaker, that sits on top of
the cabinet. This I made myself from a GL13 10 watt, 6 inch loudspeaker
unit and a grill that I purchased from Maplin. I housed it in an
admittedly rather roughly made wooden cabinet that I made for the
purpose. I find this loudspeaker to be very good in many circumstances,
particularly on the Icom. The Maplin GL13 unit is very sensitive and
has a
good frequency range.
PC Monitor Bracket:
Initially I placed the PC monitor on top of the shelf unit, but that
was really too high to view comfortably. I later found a very strong
monitor bracket for sale at a very reasonable price (£11.00) made
by IntecBrackets.
I bolted the bracket to the side of the shelving unit that houses the
equipment. The bracket articulates very well and allows the screen to
be placed in any convenient position or angle.
Shelf Unit:
Having limited space I could not accommodate a normal horizontal desk
style layout. The only scheme that would work in the limited space was
a vertical tower. I toyed with the idea of making a tall unit from
scratch, but then I saw the small, narrow book cases in a local
catalogue shop, Argos, that turned out to be just perfect for the job.
They were very cheap too, about £14.00 each if I remember
correctly, and actually very much cheaper than buying the timber and
other materials to make a unit from scratch - and certainly easier. I
bought two of these bookcases and cut one down a little to make it
shorter so that it would stand at the required height on top of the
other - a relatively straightforward task.
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Photograph showing general layout, microphone & its goose-neck and the computer screen bracket by IntecBrackets
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Tandy Optimus 33-7058
unidirectional dynamic microphone and home-brew adapter cable - more here >
Photograph showing computer screen bracket by IntecBrackets and the microphone and goose-neck in the background

Monitor bracket by IntecBrackets
IARU Grid
Square IO82VO * WAB Square SO89 *
CQ Zone 14 * ITU Zone 27 * 52:35:48N 2:12:16W * 125m a.s.l.
2 Metres and 70 Centimetres Area From MØMTJ Home QTH
The predicted plots are produced assuming these factors:
2 Metres: 50 Watts transmitter power; 2dB feeder loss; 0dBd TX antenna
gain; TX antenna height of 7 metres a.g.l.
70 Centimetres: 50 Watts transmitter power; 3 dB feeder loss; 0dBd TX antenna gain; TX antenna height of 7 metres a.g.l.
In both cases RX antenna is assumed to have 0dBd gain and also positioned at a height of 7 metres a.g.l.
The
plots are only very broad predictions - the actual area could vary
considerably due to different RX antenna height and gain, feeder losses and other
unpredictable local conditions. For reference two S point dB scales are
shown below; traditionally S9 represents 50µv with each
successive S point being 6dBV lower. However many S meters are not
entirely accurate and each S point may only represent a 4 dB gradation.
resolution
|
S1
|
S2
|
S3
|
S4
|
S5
|
S6
|
S7
|
S8
|
S9
|
6dB
|
0.2µv |
0.4µv |
0.8µv |
1.6µv |
3.2µv |
6.3µv |
12.5µv |
25µv |
50µv
|
4dB
|
1.26µv |
1.99µv |
3.15µv |
5.0µv |
7.9µv |
12.6µv |
19.9µv |
31.5µv |
50µv |
2 Metres : 144 - 146MHz:
70 Centimetres/ 430MHz predicted area plot from M0MTJ home QTH - 50 Watts - 175km map
70 Centimetres/ 430MHz predicted area plot from M0MTJ home QTH - 50 Watts - 75km map
Some older photographs of previous incarnations of the shack:
73
Mike
MØMTJ
The Station of Fred George VE2BV
- c. 1936
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This is
Frederick George, my
stepmother's father, at the controls of his amateur radio station. His
call sign was VE2BV and was located in Quebec, Canada. This photograph
was taken some time in 1936. Fred was a radio engineer at RCA
in
Montreal, as the lower photograph shows. His experience at RCA no doubt
enabled him to establish an excellent station.
The photograph
above shows a
closer view of the station; headphones, morse key, transmitting and
receiving equipment, clock and what looks like the battery power source
under the table. The 'ladder line' going to the antenna can also be
seen.
The last
photograph shows Fred George (VE2BV) at work as the radio engineer at
the RCA company in Montreal, Canada.
VE2BV is recorded by the ARRL's QST magazine as 'silent key' in
November 1948.
[Callsign update 2011: The call letters VE2BV have been reissued to Mario Boisvert of Deux Montagnes, Quebec, Canada.]
THE RADIO AMATEUR IS....
CONSIDERATE...
never knowingly operates in such a way as to lessen the pleasure of
others.
LOYAL...
offers loyalty, encouragement and support to other amateurs, local
clubs and the American Radio Relay League, through which Amateur Radio
in the United States is represented nationally and
internationally.
PROGRESSIVE...
with knowledge abreast of science, a well-built and efficient station
and operation above
reproach.
FRIENDLY...
slow and patient operating when requested; friendly advice and counsel
to the beginner; kindly assistance, cooperation and consideration for
the interests of others. These are the hallmarks of the amateur
spirit.
BALANCED... radio is an avocation, never interfering with duties owed to family, job, school, or community.
PATRIOTIC... station and skill always ready for service to country and community.
By Paul M. Segal W9EEA (1928)
I will listen and listen, and then listen again before calling.
I will only call if I can copy the DX station properly.
I will not trust the DX cluster and will be sure of the DX station's call sign before calling.
I will not interfere with the DX station nor anyone calling and will never tune up on the DX frequency or in the QSX slot.
I will wait for the DX station to end a contact before I call.
I will always send my full call sign.
I will call and then listen for a reasonable interval. I will not call continuously.
I will not transmit when the DX operator calls another call sign, not mine.
I will not transmit when the DX operator queries a call sign not like mine.
I will not transmit when the DX station requests geographic areas other than mine.
When the DX operator calls me, I will not repeat my call sign unless I think he has copied it incorrectly.
I will be thankful if and when I do make a contact.
I will respect my fellow hams and conduct myself so as to earn their respect.
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