as Oh3WE wrote
"The pair of fets have very different biases. The other one warms up and draws a lot of current, about 50 watts of idle power warms up the shack.
Nevertheless the system delivers 70 watts output (perhaps more)."
I think this amp is also configured as a dohery type. The LDMOS in the middle of the PCB is the main amp an the one to the Corner is the Peak amp.
If you supply the 28V and measure only abt 1,9A current and only the main amp gets warm then you are sure. The gate bias on the main is about 2V, on the peak amp bias about 1,8V.
If properly "snowflaked" you can expect about 30% of the rated CW power on 2,4GHz with a relatively poor effectivity of abt 20-25%. If this LDMOS are the -130 types then expect not than 85W from that amp.
Tu, giving up on this amplifier...
have you some information about modification and power supply for this amp ?
Qualcuno ha acquistato il modulo PA da 250 Watt?
Perché nessuno ne parla? ...
Perchè se chiedi in italiano forse hanno problemi a risponderti .
Because if you ask in Italian they have some issues to answer...
Just for curiosity, has 9700 the "Frequency Transverter" capability like TS2000 ?
This is very good to set up frequency indicator to 10.490.xxx and 2400.xxx for a "right" frequency information.
the RHCP polarization is right, WB and NB trasnponders have the same polarizzation, but keep in mind that the feeder must be LHCP, due to "mirror" effect of the dish that change polarization. Furthermore if you are using a helix feed, this can be user for both transponders, but it's clear that when you transmitting on WB, you cannot do the same on NB, and viceversa (but if you have two TX dish, yes).
I hope having understood your request.
Congratulations for your's operation from China.
Regards an 73.
I'm interested but this message appear when I'm trying to browse :
В доступе отказаноВозможно, не загружен индексный файл или неправильно указаны права для него.
We keep finger crossed for Michelle, it's a good candidate for a great leadship.
Maintenance has completed ahead of schedule, so the BATC & AMSAT-UK Narrowband WebSDR & Wideband Spectrum Monitor are now back open for use.
Thanks for your patience!
Thank you. The service helps all to use in a best way the wb transponder.
You doing a great service for all amateur community.
The list of lectures is getting longer:
Tag Uhrzeit Raum Thema
21. Juni 14:15 Raum Österreich DATV-Forum, QO-100: Project and operator's aspects
Jens Schoon, DH6BB
21. Juni 15:00 Raum Österreich DATV-Forum: DATV on OSCAR-100
Noel Matthews, G8GTZ
21. Juni 15:00 Halle A2, Raum 2 Geostationäre Amateurfunksatellit Es'hail-2 und der Empfang des 10GHz Downlink mit low budget Mitteln Andreas Auerswald, DL5CN (in deutsch) 22.Juni 14:00 - 15.15 Halle A2, Raum 2 Es'hail-2/AMSAT P4A (QO-100): The First Geostationary Amateur Radio Transponder
Peter Gülzow, DB2OS (in englisch)
22.Juni 15:30 - 16:45 Halle A2, Raum 2 AMSAT-P4A (QO-100) Groundstations: Experiences / Ideas / Proposals
Achim Vollhardt, DH2VA (in englisch)
Some Broadcast on our transponder ?
Thank you, I have changed the settings as you indicated but still no luck, I believe the signals on the WB transponder are too weak for this part of the world, DATV will be very difficult to rx/tx from here, although the signals on the NB are very strong.
Ed PY2RN - ..-
This is very strange. Have you tryed to experiment the change of polarization ? Are you sure about the power supply to yours LNB at 18 V to reach the horizontal polarization ?
Okay, with the suggestion of JP I have been modified the LO ref. The procedure that I have been used is to, increase and decrease, by some try, the main frequency. I found good rx at 333 K/s decreasing 40 KHz. This difference is now applied to the LO, in main screen. Inserting now the real frequency (From BATC Spectrum WB) the Minitioune locks the signal. Now I will need to try with more lower rates.
More test will be done. Stay tuned.
I belive to have the same issue.
Looking forward for a manual
Form Amsat UK :
"At the RSGB AGM in Birmingham on Saturday, April 27, 2019 two awards were made in recognition of work related to the amateur radio transponders on the geostationary satellite Es’hail-2 / QO-100.
The prestigious Louis Varney Cup for Advances in Space Communication was awarded to Peter Gülzow DB2OS for his leadership of the team responsible for the Qatar-OSCAR-100 mission which is now in service."
Congratulations to Peter for this Prize and thanks to all Amsat-DL team for all the effort.
My solution to this issue is to insert a Russian transverter (cheap but stable), between the LNB at 432 and my ts 2000 at 28 MHz. I assure the success of this solution, the only issue to cure is the gain reducing with the the transceiver or adding ad attenuator on the lnb line id the noise is too hign.