What TX amplifier do you plan to use?

  • Is anyone using this amplifier of TELRAD, from their Breeze Compact 3000 equipment?

    The boards have BLF6G27-10G as driver and BLF7G27-90L as final amplifer.

    I have added new bias supply, a shield

    and got ~20W output in DATV.





    These amplifiers seem to have been used between 2,3 und 2,5 GHz so I didn't need to snowflake at all.

    Would be interesting to know, if someone else is using these boards and their experiance.


    Regards

    Gerhard OE3GBB

  • PA5CW Bought them in 2016 on 'the Jutberg flea market' to build my first Es'hail-2 transverter. (Because of that) Others bought them too and I haven't seen them ever since. I got a mail from somebody from Italy a long time ago about how to get the pallet running and mods for 2.4 GHz. So apparently they were available in Italy too . .

  • PA3GUO

    Looks very good. :)

    By the way, the directional coupler at the output can be omitted and thus may bring a few tenths of dB more output power to the antenna. The amplifier already has a coupler built in and you can simply connect the power meter to the second MMBX socket. The corresponding calibration value has to be determined of course, but this would be necessary for the external coupler as well.

    But one could also realize a deluxe version and use the external coupler to measure additionally the reflected power.


    With the 25 euro power meter via Ali connected to the directional coupler.

  • Over the last 2 months I worked on the amp, original designed by PA3AXA, Rens.

    After eliminating all problems and a lot of optimizing after pimping the amp, I am proud to say: It´s done.

    The "next" version of this amp is running smooth and cold, with less current, lower Voltage but much more gain.


    Gain: 60dB , up to 66dB (minimum ~55dB)

    Rated constant output: 20W (SingleTone)

    Max Out: 30W but thats overkill even with low currents!

    Max input: ~15dBm! (Pluto has +3dBm @100% drive)


    It´s super linear up to 80% of its power. Hope Matthias DD1US can catch a sample to go deeper into measurements than i can do with my siglent SSA3032X analyzer. But psst, he doesn´t know that :)


    The plan is to build up to 15 pieces. Ready to use with 12V + 24V (22-28V).
    The 12V can be used as PTT or running 24/7. The heat with low currents isn´t high.

    Its mounted on a heatsink but for long term use, you should place a fan on the heatsink.


    If you are interested write me an email: dm4ds@gmx.de (please give me 1 2 days for answer)

    I hope to update my homepage soon with more informations and pictures + Videos of the measurements.


    Here are some pictures: while the minimum of my TG is -20dBm I inserted an extra 10dB attenuator.


    the PCB

    Case all will be build

    Case

    MAXIMUM Output with -13dBm input!

    After 10 minutes passic cooling @20W constant output sweep

  • Hallo ...

    an short update

    using a simple and cheap BIAS stabilisation circuit for the MRF7S21110 with good results


    Note: The BIAS CIRCUIT is (c) by dg0opk ... only for private use..... no reselling is allowed ...! (it makes no sense, look info 12.april 2020)


    73 & happy easter time ...


    STAY HEALTY Michael dg0opk


    EDIT and additional information 12.april 2020:

    i found this one as pcb version from china ...which is maybe usable for the bias circuit after a small modification


    https://www.ebay.de/itm/122214956128


    73 de Michael dg0opk

  • Hallo all...


    made today some tests with MW7IC2240 module from ebay...


    NOTE: i have no calibrated measequipment here so maybe there can be an absolute power error of 2-3dB... maybe anyone can verify and can post the results.... TNX


    here are my measurements

    2 modules were tested and have nearly identical parameters.


    PSU: 27V , idle current stage 1 was set to 100mA, idle current stage 2 was set to 500mA


    test frequeny 2405MHz, generator is ADALM PLUTO with driver SBB-5089Z + RF2126 , satsagen software


    Pin 0dBm 0.75A Pout=30dBm Gain=30dB DCinput=20W

    Pin 10dBm 1.5A Pout=39.7dBm Gain=29.7dB DCinput=40W Efficiency 22.5%

    Pin 15dBm 2.5A Pout=43.2dBm Gain=28.2dB DCinput=67.5W Efficiency 31,1%

    Pin 18dBm 3.0A Pout= 44dBm Gain= 26dB DCinput=81W Efficiency 30,8%

    Pin 20dBm 3.2A Pout= 44.2dBm Gain= 24.2dB


    the amplifier is very linear until 10-15W, max. Pout is about 25W, gain @ 2405MHz is 30dB,

    the output trimmer was turned nearly out , harmonics are > -50dBc no other modifications were needed


    It looks this is an easy and good useable amp for NB (15W) and a good driver for DATV (max.5W)...

    pictures attached...


    HAPPY EASTER TIME ALL AROUND...

    73 de dg0opk


    additional information about from 11april2020:


    like seen in the posts from UA1CCU it is possible to use one bias controller for both stages.

    I tried out my temperature compensated version for MRF7S21110 (look up in this thread) and it is working very nicely and stable over temperature. The idle current change is very low with cold (20deg) and hot heatsink (50deg).

    The Idle current of the module has to bet set to 600mA for best linearity. In DATV maybe 4W with shoulders 40dB are possible. This exactly the datasheet specification for W-CDMA systems.


    73 de Michael dg0opk

  • I am just in preparation of firing up and modifying my Nokia UMTS PA (the one with 2x BLF8G22LS-150) that I've got last year from the source in Poland mentioned here.


    In order to get a decent PWR cable connection I just made small PCB adaptors for the 2x5 pin heders (2mm types)...

    Since the price was identical for 4 pieces or 20 pieces I ordered 20 pieces - so I have many spare ones now :)

    If someone is interested in a pair of these PCBs for their amp let me know by direct message.


    73, Oscar

  • Just needed another "small" PA for a fellow OM to reach QO100 with a little bit stronger Signal than with the BU500 alone.


    Remembered the Nokia PA i bought abt. 2 years ago on a ham fleamarket (15€).


    Cut out the "small" amp (MRF21030 driving a MRF21045) from the PCB, snowflaked and put it in a old PC PSU case together with the BU500 and a fan.


    Works good to about 30W pout, clean signal.


    73s DB8TF

  • Bridge of BPF beween the two stages by wire? is it lamda/2?
    Ggerhard

  • OE3GBB


    i have not spended much time on this wire just bended it in a radius that is looks nice.


    The PA works with the expected parameters for a modified UMTS pa orginally designed for 2,17GHz.


    With 28VDD the current is about 4,4A @ ca. 30W that gives a efficiency of abt. 24% and that's what i expected.


    The IDQ was set to 200mA per MRF at first but after the "on air" test the signal stays also at 100mA clean.


    EDIT 14.04.20: just discovered that the IDq on the final MRF should be set at 200mA to improve the audio on low transmit power (ca. 250mW)


    73s