DL1BEB betreibst Du die Baugruppe mit 12V oder 13.8V?
Posts by DH2VA
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DL1BEB 13V ist zuwenig.. das sollten 14V oder 18V sein und ist auch wohl der Grund warum die LED aus ist. Bitte Kontakt mit Stefan DG8FAC aufnehmen zwecks Fehlersuche.. oder kommst Du zur Hamradio?
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Hi Gustav (please change your username to callsign DL6SIX),
The critical parameter is the symbol rate. The QO-100 beacon transmits at 2 Msym/s DVB-S2. And some satellite receivers will be able to decode this (others will have the exact types shortly..).
That said, for any symbol rates of 500 kS and below (which is most favoured by operators right now), you need probably some PC based software solution with a SDR (stick or other solution).
All the best!
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@all: when quoting signal-to-noise ratios, it is critical to indicate the measurement bandwidth as the noise is directly proportional to the bandwidth. Assuming SSB bandwidth of 2.7 kHz, which is 34 dB more than 1 Hz, your readings are 50-52 dB (@1 Hz Bw) which is what we would expect.
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@all: MTL was doing the original NXP boards, just refer them to the datasheet and the D82111 reference number. That was working 2 years ago..
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check your mail
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Great! If you can, please do two-tone with varying supply voltages. 28V is all good, but 12V performance would be a bonus.
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The board was ready to be populated.. MTL just did the board job. Component assembly and fitting the LDMOS to the heatsink was on me. But ehre are only a few components. Soldering the LDMOS to the copper heatsink was the tricky part (temperature controlled hot plate and measurement of process temperature).
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For situation 3, I have the same issue here and I think the induced offset is coming awfully close to the first null of a 90cm dish. So I am thinking about cutting a 40cm half circle out of the helix's reflector and try to reduce the offset.
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Tim, I built two of those MRF24300 and used the reference design for 2400-2450 MHz on page 6 of the datasheet. I actually got the original material with the original design number D82111 from the original manufacturer MTL in Shenzen. So they both worked :). For gate bias, I used this circuit from Ampleon:
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dj0abr excellent job! Do you have some two-tone measurements?
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Looks like RP-MCX (yes, I am serious.. somebody invented even this).
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QSL Paul about the user meeting, but please remind me on site again!
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It is a TFF1017 and it has a 5V supply going in at Pin 16, which is in your picture on the bottom edge of the chip, left pin. You should be able to trace then its origin on the board, likely the chip #1 is generating 5V and the bias voltages for the preamplifier stages.
Edit: the #1 looks like the LS7005 as noted by OH2AUE in the GM-201 mod instructions. Then it should generate 5V at its pin 12, which on your picture is the left-most pin on the top edge.
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Excellent Andreas! Where did you get the horn from?
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I can strongly support PA3FYM comments about the GPSDO. The GPS modules alone are pretty much worthless without a dedicated flywheel (OCXO) oscillator. That said, the few system which have this work very nicely.
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step-up converter to make 12V from 5V (homebrew)
And yes, it does drift but SDR-Console can handle it, doing a fantastic job locking on the PSK beacon even at these low signal levels. The GM-201 however is a bit wobbly, sounds a bit like aurora. So personally nothing I can wholeheartedly recommend.
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Thinking about a minimalistic QO-100 station, RX testing proved to be successful!
Golden Media GM-201 LNB unmodified, DVB-T stick and USB powered LNB injector. Easy copy of CW signal and probably also PSK beacon once the LNB has reached thermal equilibrium. Thing is, that the operator is also nearing rapidly thermal equilibrium..
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Minitioune V0.9beta8 out since Saturday, working like a charm! Nice dials and buttons! And a more precise MER meter (was 0.5dB , now 0.1dB resolution) with my Minitiouner V2.