DL5RDI: do you know what LDMOS is in that PA?
vy73 DB8TF
DL5RDI: do you know what LDMOS is in that PA?
vy73 DB8TF
A nice modded Ericsson SSPA for 13cm is seen here:
http://www.linkrf.ch/13cm-trvsspa.html
Looks like the one i have here.
vy73 DB8TF
Cheap measurement equipment
RTLSDR and "rtl-sdr dongle panorama" software.
vy73 DB8TF
I found a better picture of my MRF21045 Andrew amplifier, prior to the modification.
Now (after mod) with 500mW drive (BU500 upconverter max output) it delivers about 15W pout.
Maybe someone knows on which systems (i think UMTS) this little amp was used.
vy73 DB8TF
We will (hopefully soon) see how different HAMs use different methods to get good and clean signals over the bird. It will be a lot of fun for sure
Back to the "Arabsat Low Noise Downconverter"...
I found a picture on my phone of a measurement from that converter: on 1,25GHz (3650-2400) it has about 12db less gain than in the "normally" used frequency range.
But for simple equipment checks it's ok.
I don't know if this is very interesting but maybe it helps some OMs who are considering to buy such a converter.
vy73 DB8TF
DL5RDI: exactly what i mean...
I want to be sure that my signal is clean before i transmit over EH2
vy73 DB8TF
Needs the automatic RX/TX switch to be deactivated/bypassed or is this thing working on SSB without mods?
vy73 DB8TF
Here is the Andrew DS.
I don't think they need to lie about their antenna parameters.
We will see...
vy73 DB8TF
The same thing, different name
I found on ebay this interesting amplifier:
https://www.ebay.de/itm/2-3ghz…IAAOSwe7ZcOJvp:rk:25:pf:0
Not the usual 2,14GHz stuff but a WiMax? amplifier already for 2,4GHz..
But the 3 amplifiers i already own prevent me from buying this one too only for curiosity.
vy73 DB8TF
DG4BX: do you mean an "Andrew T-2400" WLAN antenna?
I have one of those here and will compare it to my 80cm dish with 4 turn helical feed as soon as we are allowed to transmit to EH2.
Those WLAN boosters are almost every time a lot weaker than advertised, and they contain a RX/TX switching circuit which maybe needs to be deactivated for HAM use.
vy73 DB8TF
Hello all,
what equipment do you use to check the SSB mod on the 2,4GHz uplink signal?
First i considered to buy an expensive receiver which works with SSB up to 3GHz but then i bought an "Arabsat Low Noise Downconverter" to use with a cheap RTL-SDR. So long its working ok, clearly there is some drift but to check the mod its enough.
What do you (plan to) use ?
vy73 DB8TF
DG0OPK writes on his HP "the FOX924 TCXO is digitally controlled and the jumps came from the controlling D/A converter. So this TCXO it not useable for SSB,CW or digimode."
and
"D75F is analogue controlled"
I refer to that.
BTW the whole link: http://www.dg0opk.darc.de/Octagon_LNB_mod_March2017.html
vy73 DB8TF
Very strange, i thought the D75F is analog controlled..
The drift looks like my digital TCXO from a few posts earlier..
vy73 DB8TF
Lucky Peter
I guess we have to wait and see under real working conditions how unmodified LNBs would work.
73s DB8TF
I took 5 minutes a look at Zoltans WEBSDR stream:
Here is the result. Look at the drift in the last 90secs.
If you can work with that ok
vy73
Hello TA2NC,
the picture you posted looks like the lower EH2 EB, maybe a little weak but you seem to be on the right sat.
Vy73 DB8TF
It would be interesting how a unmodified LNB would work if you cover and isolate it from the surrounding environment.
Maybe a block of styrofoam around the LNB could increase the stability a lot ?
I could try it but with the 30cms of snow on my roof i don't want to go up there today
vy73 DB8TF
or using a unmodified LNB with SW drift correction
We have to wait and see...