Posts by ik4idy

    Dear Heiner,


    your tests are very interesting, but how much power can manage this device ? I read a characteristic about 0 dBm, for my needs not enough. Furthermore my idea is to send signal to a converter BU500 at 144 MHz. Unfortunately this device start from 325 Mhz...This drive me to select another solution.


    73 Alex

    Hello,

    I read on another forum that this helix from Winkler isn't worth the money to spent for, return loss (SWR) should only be +-4dB and circularity looks very bad. So test it first before you use it.


    Jerry

    Oh yes I will test it. It's clear but not everyone has the availability of anechoic chamber and antenna analyzer at 2400 MHz...

    I have been built some helix for AO40, but just for curiosity I want to test the WINKLER helix. The test will be done on a 1,8 mt dish prime focus.



    73.

    maybe we can ask a ride to Elon Musk for the next test flight. Together with Tesla our satellite would be in good company.;)

    Lucio you are right ! The oppotunity for the PIII satellites may be test launch of rockets. It's clear that we assume high risk, for this reason Amsat may evaluate to built two or three unit, simplified to reduce cost, for example with only 1 trasponder. Decision about frequency isn't simple but can get major opportunities for all radio amateur.


    Or not ?

    HI Peter,

    the photo I put is taken from that forum. Maybe I should report it. I ordered this helical feed but I have not received it yet. When it will be in my hands, we will do some measure. The mechanical solution seems good and also economic.

    @IW9EZO

    Forse vanno svitate quelle due viti, tolto il collare, avvitare il connettore e rimettere il collare. Come dicevo non è ancora arrivata e quindi le mie sono supposizioni.

    Lucio, I've ordered the helix before xmas, and I received it after 3 weeks. be patient the helix coming soon. 73's.



    not too much words - just a photo. With this, I was quite succesfully during L/S-mode on AO-40- made a lot of tests with DJ1KM. In perigee we wkd sometimes with just 400mW out. Adjusted by the attentuator on 144 MHz, checked with EME powermeter - see below


    professional way to solve...may be the best solution.

    A very effective attenuator for SSB is a feature almost all (modern) transceivers have: 'MIC GAIN' ; -)

    Yes, I know. But with mic gain you have major risk to cook your converter if you forget to setup it when you come from terrestrial ssb ! :( Ok I guess you are saying :But it the same if you regulate power, if you forget to lower the power you have the same result... ok but I'm confident that this solution (regulate KW TS2000 power) is more secure than mic gain...

    I'm oriented to reduce power like OE7DBH Darko has done in youtube video. ..But i've a power budget too high in 2 mt band. I've an idea for trying to reduce power on TS2000, on the settings. I'm not interested to have full power on 2 mt, and I have skills to try some adjustment on the hidden menu. If I will have good results, I will publish it in some way.


    73.

    Yes Flo, you are right. Surely i keep the power under 0,5 W. It's an issue but we try to do this..;)

    Many people built and assemble parts to be ready on Es'Hailsat-2 for TX. But there's still a question : Are you able to apply a power regulation to avoid

    angry "Leila" on your signal ? In my opinion most of Oscar-G1 operators try to do this regulating power on the transceiver. May be a way. But there's some some difficulties because for example TS2000 has a 5 W minimum, power on VHF and UHF (may be 4 4,5 w).. For several devices you need to reduce power form 40 to 45 dB. If you want to do a regulation thru power regulator of TS2000. its clear that you need reduce more decibel. Same issue with the amplifier. The Surplus market usually provide amplifier that accept maximum 13 dBm. My BU500 has an output of 0,5 W (or more depending to the driver power). Another issue to solve, another attenuator to insert between amplifier stage and the converter.... Some one has solved theese issues or have find a solution ? I've some doubt about commercial systems too, but this is another story...

    .

    Es’hailSat said that Es’hail-2, based on the DS-2000 platform, features “sophisticated anti-jamming capabilities” for its Ka-band payload. This technology enables them to locate the Jammer with very high precision... =O

    Hi Peter,


    I've a question for you. Are Amsat control team able after commissioning to switch on or off the transponders ?


    Thanks for answer.


    Alex