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Shortwave
This is the name commonly given to broadcasts transmitted at frequencies higher than AM and lower
than TV channels 2- 13 and also lower than FM. What distiguishes shortwave bands from other
bands is their ability to propagate for very long distances ( intercontinentally most of the time).
This allows you to receive shortwave in ANY spot in the world , wherever you are.

Why a Converter?

As  telecommunications advance, cable and satellite television have become available in almost
any spot in our planet, making reception of shortwave broadcasts for obtaining news and
information at home unpractical for the vast majority of people except for some hobbyists and
experts who still enjoy this form of communication. But there are two uses of shortwave reception
which are still practical in our view.
First is portable use. It is still practical to throw in your portable shortwave receiver into your
luggage and listen to your news anyplace  in the world even if your hotel doesn't have CNN.
Second is mobile use. Although  shortwave is still considered the tradicional means of radio
broadcasting over long distances,  satellite broadcasting for vehicles has become available in
the US and has became an alternative to shortwave with better sound quality but with not so
diverse programming. An inconvenience of satellite broadcasting is that  it is not free and won't
 be so for the foreseeable future.  Reception of shortwave broadcasts in automobiles has always
been associated by the general public and therefore by the radio industry, as a difficult proposition
for mobile listeners, partly due fading of stations, partly due to oscillator drift due to vehicle
motion in analog tuners and partly due to the inability of the installers to pay sufficient attention
to noise suppression which requires similar care as receiving weak AM stations.
     As a result of this, there are presently (year 2004) very limited options for receiving
shortwave broadcasts in an automobile.

The 1st option is installing a car stereo unit which includes one or more shortwave bands among
its options. To our knowledge there are only 3 options nowadays for obtaining a complete
shortwave car stereo unit:

Sony's (cassette stereos, moderately priced obtainable from the Middle East).
Interestingly Sony has not extended shortwave coverage to CD receiver units so far (2004)
except for very high priced  units.  So buyers of these units will have  to keep listening to their cassette tapes although CD's are easier to buy nowadays .

Becker's Mexico 2340 (cassette stereo, very expensive obtainable at Mercedes Benz
            dealerships. )  Only used units may be bought nowadays.

Phillips DC 777 (used cassette stereo with good electronics and not so good plastic parts).
Hard to get these days.

What about if you want a CD player which are very popular these days ?
What about if you don't like any of the options of anyone above ?
Then you have to look at the 2nd option , that is installing a shortwave converter together
with anyone of several thousand carstereo AM-FM receivers available on the market with
every conceivable option available (with the exception of shortwave).

So , what are the advantages of a shortwave converter ?
Well, actually there are no advantages when compared to the ideal carstereo you wish
you had (AM, FM, Shortwave, TV, DSP, cassette, CD , DVD, RDS, MP3,  etc. etc. ).
But as you live in the real world where you can't have all you want , then using a
shortwave converter is the best compromise for listening to shortwave on your car and using
all other options the market offers you for sound on your automobile.
 

So , again, is there any advantage on  choosing a shortwave converter as compared to
"Let's say a Sony car stereo from the Middle East" , for example ?

Assuming that  we are talking about a digitally synthesized converter as LFB is,
then we can say that at the frequencies where both systems receive, the performance of  both
systems  is more than adequate to cope with on the road shortwave listening.

But there are some secondary considerations worth mentioning:

Removing the original OEM radio and installing an aftermarket unit with mostly different
wiring and connections can cost you as much as U$ 100 unless you can do it yourself,
besides as a rule OEM radios are better than aftermarket units.

The cost of installing a shortwave converter is generally about 1/4 of above due to the
reduced number of points to reconnect

In the case of Sony's from the Middle East, the rule is that Sony America doesn't carry
parts for those special models which in case they ever become defective, then you are
all by yourself.

In the case a converter (any brand) becomes defective, you can easely bypass it, run
your radio as before, and when the converter gets serviced then you easely connect it
back.

Often above considerations are overlooked especially the ones regarding cost of
installs.
 

So, what are the advantages of  LFB digital shortwave converter when compared to other
shortwave converters ?

1) Digital sythesized. All internal oscillators are frequency locked so you can use the converter
    with any modern digital AM-FM  without any fine tuning
2) Being a precise and stable wideband (500 kHz) downconverter, it is digital radio ready.
    As conversion from analog to digital radio proceeds. See  digital radio  ,  the converter is
   equally capable of downconverting digital shortwave into digital AM
3) Frequency hooppable and spread spectrum ready. By changing the manually operated
    band switching remote , the converter can be transformed into the front end of a frequency
   hopping shortwave receiver.
 
 

System description

The LFB digital shortwave converter is an electronic front-end  which will allow the 4 most
important shortwave bands ( 19m, 25m, 31m and 49m ) to be listened through the AM tuner
section of a normal modern digital car sound system as used widly nowadays with no driver
intervention for long time periods.
 

Mechanical Information

.The converter fits inside an electromagnetically shielded steel box 4" x 9" x 1.125"
(102 x 226 x 28 millimeters) which is installed preferably under the dashboard for vehicles
with front antennas and preferably inside the trunk for vehicles with rear antennas. The converter is controlled through a wired remote control which installs  near the steering wheel through an adhesive support.
Weight of converter is approx. 0.6 kg. (1.3 lbs).

Information for installing

                                                          Install Info

Operation

The converter has ( ONLY ! )  2 pushbuttons for operation
.Right Button is for band selection     (each push moves to the next state as seen below)

     straight_wire => AM-FM Booster => 19m => 25m => 31m => 49m => again in
     straight_wire .............and the cycle repeats each 6 pushes.

 Left Button  selects  between shortwave stations whose frequencies are even multiples
of  5 khz ( ending in 0 khz ) and those that are odd multiples of 5 khz ( ending in 5 khz ) by toggling between the two options.

Status indication  of converter is indicated by 6 leds on the remote control as follows:

            19m band 4 red leds on (15100 to 15600 khz.)
            25m band 3 red leds on (11600 to 12100 khz.)
            31m band 2 red leds on ( 9500 to 9900 khz.)
            49m band 1 red led   on ( 5900 to 6250 khz.)
             straight_wire all leds off
             AM-FM Booster green led on

            Yellow led on indicates converter ready to tune to shortwave stations that are
                              odd multiples of 5 khz ( ending in 5 khz)
                                  like 6155, 9675, 11655 or 15445 khz
            Yellow led off indicates converter ready to tune to shortwave stations that are
                              even multiples of 5 khz (ending in 0 khz)
                                  like 6160, 9690, 11680 or 15400 khz

              This display allows for good night visibility and interpretation.
 

(Note: This converter synthesizes only multiples of 5khz. You will not be able to tune to 15107 khz for example. Either you tune to 15105 or 15110 khz. Of course 99.9% of shortwave stations transmit in frequencies that are multiples of 5 khz)
 

In-band coverage: The following frequency limits are nominal values:

                                19 meter band  ( 15100 to 15600 khz.)
                                25 meter band  ( 11600 to 12100 khz.)
                                31 meter band  (   9500 to   9900 khz.)
                                49 meter band  (   5900 to   6250 khz.)

Usually the band ranges are wider than indicated above.
For example:

        When the converter works in  the 31 meter band, it will mirror the center of the 31 meter  band (around 9700 khz.)  into approximately 1000 khz in your AM radio. So if you tune to 530 khz in your radio, you will hear what you have at 9700 - 1000 + 530 = 9230 khz.. And if you instead  tune to 1710khz, you will hear at 9700 - 1000 +1710 =10410 khz. At these extreme values, attenuation will be large due to skirt selectivity of the passband filters, but frequencies like 9400 or 10000 khz are perfectly listenable.
 

Features:There is No Fine Tuning  to make!

Once you have selected your band and whether you will hear to stations odd or even multiples
of  5 khz., then you will select a shortwave station with the same convenience as selecting an AM
station on your digital AM section of your car stereo !

                   Included AM-FM Booster
The AM-FM Booster is a 10 db gain AM (6 db FM gain) amplifier usable mainly in areas where only weak signals exist. Due to the fact that these are broadband amplifiers, their use is not recommended in regions where powerful AM FM stations exist, as they are subject to overloading.
It is included for added convenience to some users.

                   Triple conversion ?
The converter acts as a double conversion front end, and with the conversion you have inside your AM radio it will make a triple conversion SW receiver.

                   Ease of operation
while driving either day or night was of prime concern in this design.

World Geographical usage:
(Warning: This design makes use of car digital AM radios used in the Americas ( Western Hemisphere ) from Alaska U.S.A. to Tierra del Fuego Argentina where adjacent channels are 10 khz apart by convention.
     If you live in Europe, Asia Africa or Australia where adjacent channels are 9 khz apart, it is recommended that you use a switchable 9 khz/10 khz aftermarket AM/FM Car Radio which are
plentiful these days. Use of a 9 khz AM radio with our converter will lead to:
          22.222 % of shortwave stations will be properly tuned
          44.444 % of shortwave stations will be off tune by 1 khz....almost unperceptible
    and 33.333 % of shortwave stations will be off tune by 2 khz.... listenable but.... somewhat
degraded ... and not too nice to your ears! )

More on usage if you live in
Europe, Asia, Africa, Australia, Etc

> I did study your webpage but I'm not qualified to understand the

> implications of the 9 or 10 kHz issue. That is, when I press the "fast"

Hi Magnus,

I will attempt to explain the problem,

Let us take the stations I listen most, these are

BBC at 15400

converter transforms to 1090 kHz (if yellow OFF) or 1085 kHz (yellow ON)

BBC at 12095

converter transforms to 1305 kHz (if yellow OFF) or 1300 kHz (yellow ON)

BBC in portuguse at 15390

converter transforms to 1080 kHz (if yellow OFF) or 1075 kHz (yellow ON)

As I have a 10 kHz step radio then my radio will tune to.....

......1060, 1070, 1080, 1090 ,1100, 1110,....1290, 1300, 1310, 1320 etc.etc.
 

so with the proper choice of yellow ON or OFF I can match 1080, 1090 ,1300.
 

but with a 9 kHz radio then

1062, 1071, 1080, 1089, 1098, 1107, 1116......1287, 1296, 1305, 1314 etc.
 

Now BBC at 15400 will show at 1090 or 1085. Here the best match is 1089

so the difference will be 1 kHz . Here you will be all right but not perfect.

Now BBC at 12095 will show at 1305 or 1300 . Here you are lucky 1305

will tune perfectly.

Now BBC at 15390 will show at 1080 or 1075. Here again you are very

lucky 1080 will tune perfectly.
 

But suppose your image was at 1060 or 1055. Then you have 1053 or 1062 to

choose from in your 9 kHz tuner. You will be 2 kHz off either way ,

this is not that good. typical ceramic filters in AM radios + - 3 kHz.

So the conclusion is: you can use the converter with a 9kHz steps but

some stations will be degraded.
 

Hope this explains your doubt.

Write me again if you don't understand.

Regards

LFB

How to find your sw station ?
In order to find your favorite shortwave station in your AM radio look at the table below for conversion offsets:
 

Band	19 m	25 m	31 m	49 m
Yellow LED OFF	14310	10790	8710	5030
Yellow LED  ON	14305	10795	8715	5025

Suppose you like to hear the BBC at 12095 khz. In this case it is an odd multiple of 5 khz so you select 25 meter band with Yellow LED ON. So it is as simple as 12095 - 10795 = 1300 khz and this is the frequency you will find the BBC  in your AM radio .

Software downloads

Design features
The converter is built around 2 NE602 mixers , has CMOS logic for low synthesizer noise, has a
wideband high-impedance front-end, has all-electronic switching between bands (only 2 tact switches(buttons) for complete operation) and is build on high quality epoxy-fiberglass PC boards.

Ordering Information
Price is U$140 plus about U$15 for air postage to the western hemisphere and U$ 20 for Europe.The converter carries with it a 2-year warranty including parts and labor assuming that the converter was not abused, and not tampered-with.Warranty does not include postage in either direction.
Money back guarantee. Test converter for 45 days. If it is not up to your expectation you can ask for a refund. Subject to the same terms as the 2 year warranty. Should you have any further question please feel free to ask.

LFB Ind. & Com. Ltda.     Phonefax 55 11 3115 0397   e-mail: swlfb@itelefonica.com.br