Posts by DD4YR

    Hello together, can someone help me to interpret the specifications in a technical data sheet?

    The FET´s data sheet specifies two performances. In the case of the MRF6S21140HS it shows:

    Typical 2 - carrier W - CDMA Performance: VDD = 28 volts, IDQ = 1200 mA,

    1.: Pout = 30 Watts Avg., F = 2112.5 MHz, Channel Bandwidth = 3.84 MHz,

    2.: Capable of handling 10: 1 VSWR, @ 28 Vdc, 2140 MHz, 140 Watts CW Output power

    Does this mean now that you can load at a bandwidth of 3.84 MHz only with 30 watts (may), in narrowband operation like CW probably 140 watts.

    How is it with DATV? Is it possible to load more than 30 watts with a correspondingly lower bandwidth (for example 500 kb/s)?

    Is the maximum load between narrowband and 3.84 MHz bandwidth linear, from 140 watts down to 30 watts?

    What can I accept?

    73´s de Robert

    ... problem solved.

    Its not the SMA plug, its the cable who is heating.

    I have now exchanged the thin coaxial cable for an RG-142. The heat development is now much lower. The 40cm piece still has a loss of about 4 watts at 60 watts of power. With a longer transmission passage, the heat development of the cable is well visible on the thermal scan ....

    So, be careful with high power on 2,4 GHz and thin cables ... :-)

    73s de Robert

    Did today my first transmitting tests with KG-STV. If you have two soundcards then you can run the program twice and then you have full duplex. You can receive what you send out in parallel. nice feature..:thumbup::thumbup:

    Hello Heiner, congrats for success!

    You need only one soundcard to receive your own signal during transmitting.

    BTW, you can also ad an secondary receive channel via BATC NB Monitor and can take a look of your correct tx frequency ....

    And, make a mouse-click in the waterfall, and you get an other better rx-monitor ...

    73´s de Robert

    Is appreciated.

    It´s a 50 Watt slug. (2400-2500 MHz)

    I get at 1,5 watts input power 50 watts output power. My driver is only 1.75 watts.
    With 1.75 Watt the pointer of the Wattmeter goes to right "stop". Should be estimated then 60 watts .. (by 15,3 dB gain)

    Full duplex Operation is not possible with this PA (neither with the unmodified PA nor with the PA modified in the mentioned way).

    .. sure, but only for one band, 2,4 GHz.

    For QO-100 you need only the tx part of this pa. So, full duplex (tx on 2,4 and rx on 10GHz) is still possible.

    I think, what Thomas means, is the SSB problem with the vox in this pa type. During a ssb signal you have different output levels, so the vox will switch on and off during this tx period. (cause its still a carrier/no carrier vox)

    With modification, you have current the tx status, and are able to work in SSB via QO-100 in full duplex mode.

    73 de Robert

    The requirement has existed in Germany for over 2 decades.
    Create station description with all requirements.
    Send a table with the data to the RegTP. Station descriptions with all calculation bases and antenna radiation diagrams must be available, but will only be sent to RegTP upon request.

    I´ve done the "Selbsterklärung" 20 years ago, using the programm "Watt32" which includes all forms. no problems.

    Forms are available here:

    73 de Robert

    i made some tests to receive the WB Transponder on small dishes to compare maybe with others.... please give information about your results...!!

    Hello Michaell,

    great work! Thanks.

    Whats about the weather conditions?

    I observe different reception values depending on the weather, clouds, humidity etc.
    It would be interesting if in all measurements a parallel operated "reference antenna" would be measured to take these weather effects into account ....

    73s de Robert