Posts by iw5bsf

What should I look for beyond pcb ad8302

hello dd0kp

Thanks for the information, arduino UNO standard if I'm not wrong? I've never used it

Thanks, I see in the image that you used a 2x16 line display and a swr gain stage and an ebay kit? what you use



73 Roberto

Quote from SV1BDS

Hi,

A AD8302 dB diff & phase is build based on a eBay ready PCB which display also SWR. A ATMEGA8 displays on a 2*16 LCD.

hello Geotge , on ebay pcb swr display based link ? I was interested in building it to make measurements on my feed

73 de iw5bsf Roberto

No for the tests I used low loss Gore brand cables but not suitable for outdoor use h155 I don't think it is suitable 2.4ghz

hello Thoma sorry uplink I meant 2.4 GHz between PA and helix a low loss cable

Roberto

Did I forget that the coaxial cable used 2.4 ghz?

Roberto

hello Thomas right observation !!!

Roberto

thanks Ed PA1EW I try to build it while I wait for your answer, I realized that I was inspired by your photo but using a reflector I had the propeller 125x125 and centered but slightly above the return loss of 28 db trying a second transponder with 2watt and dish offset of 80 cm the return signal s7

Roberto

Quote from PA1EW

I want to present my design for a single-dish portable station as described below and partly shown in the pictures. For me it should meet the following requirements:

·       Easily detachable construction (transport by car)

·       Single offset dish 60cm, dual band feed

·       Stable tripod mounting

·       Comfortable adjustment of dish heading

·       Compact “radio-box” to carry two full-duplex transceivers + SDR

·       12V operation (battery) possibility

A new adapter bracket (picture 1) was constructed to mount the Triax 64 dish in a stable way to the tripod pan-tilt head. The dish's own (elevation)adjustment is fixed and not used. Another bracket (left side in picture 4) is added to carry the plastic box with Mini-GPSDO 27,841846MHz + 30MHz low-pass filter + battery pack 5V.

As my modified Octagon LNB was readily available to be combined with the 5,25 turns LHCP Helix, I choose this for the moment above the patch-feed to be used as dual feed. The Helix/LNB mounting has been improved from the quick-and-dirty tape-construction to the detachable- and adjustable Helix-reflector mounting as shown in picture 2 & 3.

The construction allows also for LNB skew-adjustment rotation at any time. Releasing the two wingnuts (pictures 2 & 3) on the sides will then allow for LNB –focus adjustment, the Helix reflector is moved too. The Helix reflector is held in place also by the front-section of the Octagon LNB.

Last item to be finished is a compact housing for the FT817 (144MHz TX driver) and a TM-455E (435MHz RX). The modified MKU2424A (=B) up-converter will be placed on top. A compact 13.8VDC/22A SMPS supplies the power when 230VAC is available, when not, a 12V gel-battery could be used. Hook-up for SDRplay RSP2 is also foreseen. Hope to work you soon via QO-100 with this portable station!.

I am curious who has similar- or totally different portable constructions, please let us know and show.

73 Ed PA1EW/P

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Hi, what size did you make the reflector in mm? and relative distances

73 of iw5bsf Roberto

sorry all post me I correct 0,5 A IR , hello db8tf excuse me model model of the daiwa

Roberto

Quote from DB8TF

Just finished modifying another UMTS PA (BLF8G22LS-160BV) this time for OM DM4DS Sandor.

Max power easy over 100W but as my power attenuator gets very hot i stopped @ 100W (320mW drive).

Signal looks clean on spectrum analyzer.

I attached some pictures from the testbench and the used equipment.

73s DB8TF

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Hi great, I see you use the Daiwa power meter but the power returned 2.4ghz?

Roberto

Ok, I solved PA now works at 13 watts and 0.5 mA, as a driver for tests of use of Chinese Tiquin 27 dbm out ebay but personally I don't li

73 Roberto

hello om0aao,

I did some tests in PA and the draiver seems to resonate a lot due to the length of the connection cable that probably resonates and influences the power supplied

Roberto

thank bg0aub

thank BG0AUB , I made some improvements by obtaining with input 0.5 at the output 2 watts bias 3v and with 3.7v bias 9watt

vcc 27v

73 Roberto

Quote from BG0AUB

For mrf21045, my bias voltage is 2.7-3.0, 0.55-0.9a at 24v, and 42DB is output when 30DB is input

thank you all, sorry, but the 500 mA current must be measured on the Vg? bias MRF2104

Andrew MRF21045 helps what value should the polarization voltage have? I got about 3v 1 watts 0.6a or so with 3.3v 0.8a 2.5 watts if I increase the bias voltage 3.4v starts consume rest

Thanks, you get more output than you think is possible

hello the lines were not 50 of entrances and exits using copper I managed to obtain with +4 db input in out 1 watt 2.4 ghz with 20 v of power supply

Roberto