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CW & QRP Clubs

MIZUHO QRP TRX

QRP TRX for Sale

 

 

FOXX-3 QRPP CW TRX for experiments

Camper 1 - CW TRX with No compromise

 

 


Amateur radio is fascinating hobby which enables millions worldwide to communicate with each other by many different means. Amateur radio is a hobby for everyone interested in communicating…

Amateur radio is responsible for putting hundreds of thousands of poeple all over the world into direct contact with each other every day.

World wide there are two million licensed radio enthusiasts spread across virtualy every country, who are free to operate from the comfort of their own homes.

Age, profession, nationality, political and ethnic barriers are non existent, thus promoting international friendship and understanding. Amateur radio can be enjoyed by young and old, male and female and even the most severely disabled can make friends around the world from their own home.

Contacts may be made using Morse code ( telegraphy mode) or speech, between computers and even by television. Radio amateurs have built satellites for their own use.

Because radio amateurs are permitted to use a wide range of frequencies and transmission modes, they must be qualified operators. Training is available from radio clubs or technical colleges, depending on the qualification needed. A novice licence scheme available in many countries provides an easy way to become a radio amateur.

Amateur radio can be enjoyed in many different ways. Some of the ways in which you can enjoy this interest are:

Telegraphy contact ( CW ) using the Morse code – using a series of dots and dashes transmission can reach further distances than speech. It is also an international ”language” allowing contacts all over the world.

Voice contact – using the microphone linked to a transmitter / receiver.

Satellite transmission – international contacts are possible by bouncing communications off satellites orbiting the earth. Radio amateurs take an active part in designing and building satellites for their own use.

DX peditions – an amateur radio trip. This can be anywhere from the North Pole to remote unheard of islands, to your foreign holiday, or remote uncharted jungles.

(thanks to RSGB web pages)


Next pages are devoted exclusively to Amateur radio. You may find here some stuff concerning CW, operating and technical news. I am trying to keep this page as interesting as possible, so no boring personal data included.


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I'am member of a few CW clubs and fun-groups & there are links

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There are some basic informations about my favourable QRP equipments for HF backpacking operations…


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MIZUHO HF CW/SSB HANDHELD

QRP TRANSCEIVERS from Japan.

 Do you know MIZUHO ?

MX-21S, 2W SSB/CW Transceiver…

 

I purchased my first MX-21S as a used radio in 2002.

This is first QRP rig from Mizuho, Japan for me and till now working excellently.

It was assembled product in Mizuho, but there was possibility to buy the Kit also,

where PCB completed with all components and adjustments ready for wiring the switches

and buttons only. ( Not available now )

NB2(noise blanker) is option item but Kit model was in-expenssive.

I was enjoyed during many QSOs with MX-21S.

In CW mode, it is not difficult to make QSO with many DX stations on 15m when a bit solid antenna is used !

 

 

 From the MIZUHO history …

If there is one Mizuho radio most QRPers are familiar with it's probably the MX series SSB/CW HF handhelds, though not everyone knows them by that name. The two watt HF and one watt VHF versions introduced in 1983 are still in production. The series celebrated it's 20th anniversary in 2001, making the Mizuho MX series handhelds probably the rigs which lasted longest on the market of any ham transceivers ever produced, and they are still going strong. If you don't know them under the Mizuho name, perhaps you've seen them as the AEA DX-Handy, or with the Pico brand name, or with Santec's JIM nameplate. Models have been made for every band from 80m up through 2m including 12m and 17m. Only 30m has been excluded. The MX series remain popular with QRPers the world over.

The first of the series released was the MX-6 a 250mW 6M SSB/CW transceiver which ran on a single nine volt battery, was released in Japan in October of 1981. In August, 1982, an improved version, the MX-6Z, was released, and was quickly followed by a 200mW 2M version (model MX-2) and a 300mW 15M version (model MX-15): the first Mizuho HF handheld - MX-6. 10 meters was added to this series in August of 1983 with the 300mW MX-10Z. Note that all the models after the MX-6 added a noise blanker and replaced the second antenna jack and the phone jack with a more traditional speaker/mic. arrangement. The MX-10Z and later production MX-6Zs also used six AAA batteries in place of the nine volt batteries. The milliwatt Mizuho handhelds were successful despite the miniscule power output. They, like most Mizuho products, were sold both as kits and as built and tested radios. The 200-300mW Mizuho rigs, along with the better known one and two watt rigs, were initially distributed in the United States by Ace Communications or Irvine, CA. Accessories for the early versions of the MX series rigs are now hard to come by. Many of the accessories currently made simply do not fit or work with the early rigs.

In May, 1983 Mizuho broke new ground for the series with the release of the MX-6S. This radio has been in production ever since, and almost all subsequent Mizuho HTs are based on this model. The MX-6S spoted many new features: a full watt of output power, an S/RF meter, RIT, a charging circuit for NiCad (or later NiMH) batteries, and later an RF attenuator was added as well. The volume control was moved to the top of the rig as another rotary knob, and the latching PTT switch found on the milliwatt versions of the rigs was replaced by a more conventional momentary switch. The mode switch was shifted to the bottom of the rig. The MX-6S proved immensely popular, and was quickly joined by the MX-7S for 40 meters and the MX-21S for 15 meters. Mizuho now had handhelds for the three Japanese novice bands.

The line was gradually expanded to include models for all the remaining HF bands except 30 meters. Additionally, Mizuho introduced a number of accessories, including the CW-2S sidetone/QSK unit and a series of 10 watt amplifiers. A mounting bracket to contain the entire "system" and, in effect, create a mini mobile monoband HF station was released.

In the mid '80s Ace Communications sold most of the Mizuho line in the United States under the Mizuho name. After they disappeared, AEA picked up the MX-6S and MX-28S (2 watts on 10 meters) and marketed them as the AEA DX-Handy. By 1993 jCom had picked up the line and sold the MX series as their Pico transceivers. When jCom went out of business Ramsey Electronics bought out and sold off their remaining stock but did not continue to import Mizuho products. Mizuho equipment has not been distributed or sold commercially in the United States or Canada since the mid 1990s.

(Thanks to Caitlyn Martin, KU4QD)

 

 the first of the series released was the MX-6 a 250mW 6M SSB/CW transceiver

 

Models of Mizuho QRP Transceivers Available

------------------------------------------------------

MX-3.5S: 80 Meter Band 25Kc. per XTAL

MX-7S : 40 Meter Band 25Kc. per XTAL

MX-14S : 20 Meter Band 50Kc. per XTAL

MX-18S : 17 Meter Band 50Kc. per XTAL

MX-21S : 15 Meter Band 50Kc. per XTAL

MX-28S : 10 Meter Band 50Kc. per XTAL

MX-6S : 6 Meter Band 50Kc. per XTAL

 

Please note that each radio will take a maximum of two crystals at

any one time.It is a simple task to change crystals as they just plug

in the transceiver underneath the cover. ( no other adjustment

needed)

 

GENERAL SPECIFICATIONS OF TRANSCEIVERS

---------------------------------------------------------------------

Construction : Metal case throughout

 

Frequency ranges:

-------------------------

MX-3.5S : 3.500-4.000 Modes LSB/CW

MX-7S : 7.000-7.300 Modes LSB/CW

MX-14S : 14.000-14.350 ModesUSB/CW

MX-18S : 18.068-18.168 Modes USB/CW

MX-21S : 21.000-21.450 ModesUSB/CW

MX-28S : 28.000-28.600 Modes USB/CW

MX-6S : 50.000-52.000 Modes SSB/CW

 

Semiconductors:

---------------------

4 ICs, 13Trs., 6FETs & 37 Diodes

 

Power supply voltages:

------------------------------

Internal 8.4-9VDC

6X AA drycells

7X Nicads.

When using drycells use supplied dummy battery.

External 9.5VDC

Do not put 12V directly into the rig unless using optional DC/DC

converter or charging internal nicads !!!

 

Power consumption:

--------------------------

RX 70mA ( at no signal)

TX 620mA (maximum)

 

Frequency stability:

--------------------------

+/- 500Hz At power-up

+/-100Hz at 25 deg. C after 30 Min.

 

Antenna impedance : 50 Ohms

Dimensions : 2.6" x 1.5" x 5.6"

Weight (including Batt.) :

MX-3.5S 645g.

all others 590g.

 

TRANSMITTER SPECIFICATIONS

---------------------------------------------------

Maximum power output : 2 Watts

(1 watt MX-6S 6 meters)

Spurious radiation: -40db

Modulation: Single sideband (suppressed carrier)

Carrier suppression: 40db minimum

Crystal filter sideband suppression: 40 db minimum

Harmonic Levels:

====================

2nd -63dBc

3nd -59dBc

4th -76dBc

5th <-90dBc

6th -82dBc

7th -80dBc

8th <-90dBc

9th <-90dBc

 

Built in microphone, LED transmit indicator and mini CW key-button on

top panel

 

RECEIVER SPECIFICATIONS

--------------------------------------------

Receiver method: Single conversion superhet

Sensitivity: S/N 15db at 0.5uV input : Attenuator in 0.22uV

Selectivity: -6dB 2.39kHz : -60db 4.55kHz

Blocking: Measured as increase over 12dB SINAD level of interfering

signal with an unmodulated carrier, causing 6dB degradation in 12dB

SINAD on-channel signal:

Separation Rejection

=====================================

+/- 10kHz 72.5dB

+/- 100khZ 76.0dB

+/- 1Mhz 91dB

+/- 10MHz 93.5dB

 

IF and Image Rejection: Increase in level of signals at the first

i.f. image frequency, and at the i.f. it self (11.2735), over level

of on-channel signal to give identical 12db SINAD signals:

Image <100dB

IF 73dB

 

3rd Order Intermodulation Rejection: increase over12dB SINAD level

of two interfering signals giving identical 12dB SINAD on-channel 3rd

order intermodulation Product, 10KHz signal spacing:

Attenuator Out 53.0dB

Attenuator In 60.5dB

Intermediate frequency: 11.2735 MHz

RX Includes: Crystal filter, AGC, noise blanker, built in S-meter

 

LOCAL OSCILLATOR

-------------------------------

Oscillation method: Variable crystal

 

CRYSTAL SPECIFICATIONS

----------------------------------------

For MX-28S:

Funamental mode

60 pF internal capacitance

0.0010 % tolerance

HC-25 case

 

CONTROLS

-----------------

Top panel: Rit. , AF volume, Tuning, Noise blanker, Crystal switch,

S-meter, External Speaker and Microphone jack, mini CW key-button, BNC

antenna jack.

Bottom panel: Power supply in, Charging switch, RF Attenuator, SSB/CW

mode switch, Jack for external key.

 

Optional Mizuho Accessories

-------------------------------------

Telescopic whip antenna AN-..series, CW side-tone unit CW-2S, 10 Watt linear PL-.. series

amplifier, AC power supply, DC-DC converter PM-1, Carrying case, speaker mike, Mobile

rack.

 

Official Mizuho representative: 

With JA1AMH, Mr.Takada-san of Mizuho, who is standing behind their new small KX-QRP

wide-range antenna tuner. (Thanks to JA1CQT for the photo.)

 

Currently available Mizuho QRP gears …

We are not related MIZUHO company at all.These are currently

available MIZUHO QRP products list with my comments here

just as an information to foreign QRP friends. You can purchase

them 10-15% off at amateur radio retailers in Tokyo ($1=YEN125.).

 

Transceiver(We call them Pico series):

MX-6S 32,000yen 50MHz SSB/CW 1W

MX-7S 32,000yen 7MHz SSB/CW 2W

MX-21S 32,000yen 21MHz SSB/CW 2W

PL-6S 21,600yen 50MHz Linear 10W

PL-7S 21,600yen 7MHz Linear 10W

PL-21S 21,600yen 21MHz Linear 10W

 

Comments: The smallest CW/SSB transceiver in the world.

S/RF meter, Noise-branker, Attenuator installed handy

talky type QRP rig. VXO A/B channel selection of each

50Khz(below 7MHz:25KHz) coverage. IF is 11MHz.11Tr 3IC.

The company sporadically make 3.5,14,18,28MHz version.

It is very difficult to buy them because many amateur

want to have it. Now only completed Pico transceiver

is supplied. I suppose many failed to complete kit and

troubled company.

 

Options for Pico:

PM1 3,300yen DC-DC converter

MS-1 4,600yen SpeakerMic

PR3-S 4,500yen Lack mount (MX,CW-2S,PL)

CW-2S 8,400yen CW semi-break-in unit /w sidetone

BM-6 1,500yen lather bag

PS-2 3,600yen AC adapter

Crystal 1,800yen any desired 25/50Khz band

PAN-62 5,200yen pocket dipole 50/144

AN-50 3,600yen 50MHz lod antenna

AN-7 4,800yen 7MHz lod antenna

AN-21 4,800yen 21MHz lod antenna

 

Comments: Pico need 9V power (AAA battery x 6). Feeding

12V will destroy the unit. I think the DC-DC is expensive

you can make 9V with 7808 and one Di between the GND.

CW-2S is recommended for CW operation.

 

Kits and misc.:

QP-21 3,000yen 21MHz 1W CW transmitter

QP-7 3,000yen 7MHz 1W CW transmitter

CK-1D 9,000yen Currtis Electric keyer

VFO-5D 6,000yen stable 5-5.5M VFO module

VFO-5D 6,000yen stable 7-7.1M VFO module

MA-1 1,300yen audio amp module

MA-20A 2,000yen Mic amp module

PF-1A 2,500yen CW peak filter module

KX-50K 8,000yen 50MHz antenna coupler

 

Comments: QP series are the most famous kit with fixed crystal.

It does not change the price more than 10 years. The VFOs are

sealed module with iron case.Japanese QRPer use this unit to

avoid difficult unstable VFO problem which annoys other station.

 

"MIZUHO" means beautiful riceplant. The owner JA1AMH Mr.Takada

named his company as he wish everyone to remember the beautiful

country and free quiet life with his QRP radio goods in this

busy world.

I am no relation with MIZUHO. Just a user enjoy MIZUHO.

( Thanks to Junichi Nakajima / JL1KRA )


So, I hope that answers any questions you may have about the rigs…


 

My latest QRP QSOs with MIZUHO MX-21S… (updated 21/7/2003)

IT9, EA6, UN8, OY ( I heard P29, YB0 and also YC7 from Borneo but no QSO...)

...all with MX-21S Mizuho tcvr into the 1.7m long mobile whip with magnetic base

on the cars roof connected thru transmatch, SWR meter and powered by DC-DC

home made adapter from cars battery.  

The best 2-way QSOs with MX-21S transceiver 1.5W output into the vertical HF6V located in Kostice, locator JO60XJ, county ELO, Czech Republic :

ZL, W5, 3B8, OX, YV, TR, PY, 3V8.

 

Technical news… (updated 21/7/2003)

I am working on the user friendly DC-DC converter for MX-..S series of the MIZUHO handhelds for all of the users they are need it for external DC power supply operation higher than 10V. Small black box with simple function, cheap and usable displacement for original equipment PM-1 from Mizuho. At the moment it is under development and testing.

Latest DC-DC converter for MX-..S series ver. 1.2. works great and building is really cheap.

I am preparing small kit of the DC-DC converter for sale !

I am still testing the another beta ver. 1.2. Bandpass filter for MX-21S cause last one had too much insertion loss.

I am also working on simple option for easily CW operation without necessity to use original CW-2S kit from Mizuho. I have arranged very simple kit which makes the same functions as the CW-2S and works very nice. Now under beta tests...

Latest project is mini PA excited by Mizuho MX-..S for 100W output power when used in fixed QTH only for $80 only !

Another developments will be soon !

 

I am able to repairing your Mizuho MX..S handhelds from now !

If you have any troubles with Mizuho (mainly in EU) then contact HOT Line ...

New HOT Line: Click here to mizuho.europe@seznam.cz for asking directly if you have any questions, requests, orders or technical troubles. Thanks. Petr, OK1RP

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Japan MIZUHO handhelds FOR SALE :


A List of New and Used MIZUHO Radios available in Japan only !!!


Last update 21-7-2003. Copyright OK1RP & OK1-35506.


Used Handheld HF TCVR MX-21S. 15m CW/SSB/2W,noise blanker,attenuator,

VXO (2x50kHz),S-meter + W-meter,superhet + 4xtal filter. 2xSSB band xtaled.

Radio is used, but good conditions and functions, minor scratches only!

Price is now

in special…additional discount only for

150,- USD !!!

Contact indians@seznam.cz, 00420608230010


Another equipment from Japan FOR SALE:


NEW ! Mizuho SX-9S QRP tuner.

Specifications: Freq. range: 3-54 MHz. Max. 10W thru power.
Input impedance: 50-600 ohms. Dimensions: 162 x 55 x 130mm
Weight: 800gr

Ideal for FT-817 or Mizuho handhelds !

Price call for price ( New one ! )

Contact indians@seznam.cz, 00420608230010.


Mizuho MX-14S, MX-18S, MX-24S, MX-3.5S discontinued !!!

Only used ones can be found


Terms of Sale:

Payment by International MONEY ORDER / VISA / Eurocard / Mastercard or CASH ONLY.

All prices are NOT including the shipping/insurance taxes from Czech !!!

Call for shipping cost which is different according to landing area, approx. 15-30USD.

Conversion to other currencies according to actual rate of exchange in OK. indians@seznam.cz

I am an individual, not a business! So makes a help with Mizuho gears in EU only.
Will ship only as a global priority - cheapest way.
!!! Used items are tested for transmit and receive. But as with all electronic gear, there
are no warranties implied !!! Click here to indians@seznam.cz for asking directly if you have any questions.
Thanks. Petr, OK1RP

Items are shipped next business day after payment arrives !!!


I am able to repairing your Mizuho MX..S handhelds from now !

If you have any troubles with Mizuho (mainly in EU) then contact HOT Line ...

New HOT Line: Click here to mizuho.europe@seznam.cz for asking directly if you have any questions, requests, orders or technical troubles. Thanks. Petr, OK1RP

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FOXX-3 - QRP CW TRANSCEIVER kits

for HF bands from Kanga Products, U.K.

- your home brew QRP experiment…

 

( From the kits manufacturer - Kanga Products, U.K. web pages …)

You may have heard of the Pixie, the VU Mini and the Micro 80. All of these transceivers use the PA transistor as the receive mixer, but the original idea came from the UK and the well-known QRPer George Burt GM3OXX in 1982. It first appeared in SPRAT in 1983.

The FOXX-3 is the latest version of the ever-popular FOXX. Designed by Derek Alexander, it incorporates a sidetone oscillator, changeover relay and low-pass filter. It fits inside an Altoids (TM) mint tin and all connections are made via vertical connectors which are concealed when the lid is closed. The connections are as follows:

 

 We also supply a small PCB-mounted switch which can be used as the key for ultimate portability. All you need to add are a 12 volt DC supply, headphones and an antenna and tuner. The picture shows the first FOXX-3 built on a production PCB. Note the screen printing which identifies all component positions. The optional push-switch Morse key is fitted. Richard Newstead, G3CWI, recently operated a 40m FOXX-3 from the summits of Snowdon and Scafell Pike, the two highest peaks in Wales and England, in a single weekend. Despite sub-zero temperatures, Richard made 20 contacts in a total operating time of 80 minutes. Richard told me, "FOXX performed brilliantly. Sidetone stops at -10 degrees C but radio still seemed OK." "I didn't build any additional filtering for the FOXX and it worked really well. No BC breakthrough at all on either day."

Thanks for the info, Richard, but I won't be testing it at -10 C myself.

The FOXX-3 was launched at the Rochdale QRP Mini-Convention on October 28th 2000.

FOXX3 Construction Pictures

The change in ownership of Kanga in the UK has been accompanied by a change in the documentation in the new kits that are coming out of Kanga. The pictures below are pictures I took while assembling a 20 meter FOXX3 kit. Although it is hard to tell from the pictures, the documentation breaks down the construction of the kit into logical stages, and each stage is tested and working before work starts on the next stage. The 20m FOXX3 I built and documented in these photos worked at turn on when it was completed.

The kit comes with each stage in a separate plastic bag, so there is no sorting parts. Even the parts list in the documentation is split up by stage.

FOXX3 Construction Pictures

The change in ownership of Kanga in the UK has been accompanied by a change in the documentation in the new kits that are coming out of Kanga. The pictures below are pictures I took while assembling a 20 meter FOXX3 kit. Although it is hard to tell from the pictures, the documentation breaks down the construction of the kit into logical stages, and each stage is tested and working before work starts on the next stage. The 20m FOXX3 I built and documented in these photos worked at turn on when it was completed.

The kit comes with each stage in a separate plastic bag, so there is no sorting parts. Even the parts list in the documentation is split up by stage.

 

The audio stage after completion.

 

This photo is after the keying stage was added. It also shows the documentation for the construction of the keying stage. You should be able to make out the schematic, parts list, and layout of the keying stage (only) parts. The instructions for this stage are on another page in the documentation.

 

The Oscillator stage is then added....

And finally the output filter is added. One of the things that is not obvious from the photos is that there are several connector options supplied with the kit. There are multiple ways of connecting the key, power, and antenna. All the connectors are supplied, and they all can be mounted directly on the PC board. All that is left for you to do is put it in an enclosure. Directions are given for installing the FOXX3 in an Altoids (or similar) tin.


There is the comments and experiences with assembling the kit …

( by Jim, W4JBM and myself Petr, OK1RP)

I was impressed with the quality of the board. There was an omission in the instructions that came with very early FOXX-3's (installation of capacitor C10). The capacitor was included, there was a place for it on the board, and it was shown in the schematic so it wasn't rocket science to figure out I needed to install it. This omission was corrected in later releases of the kit.

The only problem I had was the testing after stage 4 (assembly of the crystal oscillator). My oscillator didn't work through the full VXO range. After some study, I decided that it would work once the oscillator was loaded by the mixer/PA stage. This was verified with a temporary load and things worked fine. Once assembly was complete things worked as expected.

This is an incredible little rig. Automatic TR switching, a sidetone, VXO, RIT, and can be powered by a 9 volt battery.

The only weakness is total gain for the receiver. Usually if they can hear you you'll be okay. But I use mine with an amplified speaker for more gain. This combination works great!

I've taken it to club meetings and ham fests. It never fails to get comments. A couple of no-code techs have said now they understand why they should bother to learn the code--something this simple and yet useful.

So if you get the chance, get the kit and put one together. Maybe I'll see you on the air for a 2-way FOXX-3 QSO!

The best 2-way QSOs with FOXX-3 transceiver home brewed with 250/500mW power output into the vertical radiator located in Praha, Czech Republic :

JA9, ZL1, W1, mni EUs like G, OH, LA, PA, I, 4X4, SM, YU, LZ etc.


Technical news… (updated 21/7/2003)

Cause of lots BC breakthru during the nite operations I am working hard on improvement of the RX by the enforced filter on the basic board and additional filter in extra minibox.

From 1st April 2003 I am still testing another beta ver. of "on board" filter giving min. -55dB on BC freq. Last HPF gives good 40dB attenuation on BC band but insertion loss is too high. Latest filter works good but its larger than standard Altoids box...looking for another architecture of the filter or another box?! J

If its possible then use as good as possible shielding for filters and self tcvr.

Now under development and testing… 

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Camper 1     fully modular architecture and Highest Performance CW tcvr for HF CW with No compromise from CONTIWA …


 

 CONTIWA

   

 Camper 1

160-10M High Performance and No Compromise CW Transceiver with fully modular architecture.

 Project Product Description ( updated Jul 2003)


Easy to Build:

 

Camper 1  Highest Performance and No Compromise CW Base Unit

 

General Features:

 

confidential cause of under development and construction. Will be shared when testing will be done.

 

Receiver:

 

Camper 1 Performance Measurements (14MHz Typical Values)

MDS(dbm)

IMDDR3(db)

Ip3(dbm)

Ip2(dbm)

BDR(db)

*

*

    *

     *

*

  * confidential cause of under development and construction. Will be shared when testing will be done.

 

 

* confidential cause of under development and construction. Will be shared when testing will be done.

 

CW Features:

 

* confidential cause of under development and construction. Will be shared when testing will be done.

 

Would You like to have the legendary radio like Harley & Davidson is in the motorcycles world ? … then wait for

Camper 1 from CONTIWA! J

 

(Specifications subject to change without notice)


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Last update 21-7-2003. Copyright OK1RP & OK1-35506.