What 4.096V regulator did you use, LM4040D41ILP ?
Posts by PA3FYM
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Hi,
Lets suppose that we have two OCXO one in 10 MHz and one in 100 MHz with the same phase noise at the same offset.The phase noise is increased by 20log(N) dB) where N is multiply factor. In our case N=10, so we have 20 times larger noise. It meens in simple words that if we create 10 MHz from 100 MHz it will have 20 time less phase noise or if we create 100 MHz from 10 MHz it will have 20 times larger phase noise. It is obvious that when we produce 25 MHz from 100 MHz the phase noise will be less than produced from 10 MHz. One calculation that I have done is that phase noise produced by multiplying by 390 (9750/25) is about 50 times bigger!!!
The ECOC-2522-100.000 existis in various versions with similar prices and different ppB, so a small ppB is prefered as has better stability... PA3FYM AOCJY1-100.000MHZ seems a good choise for GPSDO available from Mouser at half the price.
George, it's 20 dB more / less phase noise. Anyway .. that's exactly why I -from the beginning (end 2018)- beated on the drum concerning PN of the LNB reference and use(d) crystal filters for purification.
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Hi Peter, despite I was not home last Thursday evening (and therefore couldn't witness the issue)
perhaps the AGC values of the NB-transponder (when they are logged) may give a clue?
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Looks good George!
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Hi George,
That is an interesting 'Way to Rome' and I am surprised that the HC74 can cope with 100 MHz ?
Where did you get that 100 MHz OCXO?
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Feng showed me the inside of his LNB. It has an RDA3566 chip, which doesn't have a 'symmetrical oscillator' (aka kalitron), so 'balanced' feeding does not work. It works perfectly for the NXP chips like I revealed/published in 2019 (or so).
For the RDA-chips there is an 'input' and 'output' pin (where injected levels differ around +20 dB (relative to the input). -
Edit: The FT-857D is not full-duplex capable, you need a 2nd receiver. Is this the "problem" ?
My definition of a 'problem' is an 'un- or suboptimal solved issue'. Because I have no 'issue' with transceive mode, I have no 'problem'. 😇
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Yes, I had this from the beginning (12 Feb 2019) but nobody understood me
and I was 'crucified' for (suggesting) working 'simplex'. 😇
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The small loop with marker 1 is the loop you want to try to get into the center of the Smith Chart.
Try to fiddle with the patch edges/corners and decrease, like G0MJW said, the sweep to 2.3 - 2.5 GHz.
Your results look nominal, but need some tweaking.
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PA5CW Bought them in 2016 on 'the Jutberg flea market' to build my first Es'hail-2 transverter. (Because of that) Others bought them too and I haven't seen them ever since. I got a mail from somebody from Italy a long time ago about how to get the pallet running and mods for 2.4 GHz. So apparently they were available in Italy too . .
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ON4CJQ It applies to the uplink facility. Remember, (not to you personally) you are working through a facility which is not yours.
So, the owner (Es'hailSat) decides which users he (it) accepts on his space vehicle.
It's the same as that you decide who enters your living room at home. Because it's your house.
There are no technicalities involved , it's the owner who decides, like you in your own house / living room.
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The satellite operator, in this case Es'hailSat, has the right to define which or what kind of 'operation' they allow on their satellite(s). After all, the satellite is owned by Es'hailSat and not by us. For the QO-100 transponder Es'hailSat delegated governance to AMSAT-DL.
The reason why the satellite operator has this point of view is simple: reduce failure factors. QO-100 is aboard a commercial/professional space vehicle with other (paying!) users/customers with well defined service level agreements (SLA's).
Bear in mind that from a professional perspective it is 'odd' that a satellite operator allows 'non coordinated' users on/through their space vehicle!
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Girls included !
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Herewith I would like to congratulate and thank the AMSAT-DL team with the result of doubling the NB tpx bandwidth
and fulfilling the wish of a FSK CW beacon (with continuous carrier).
Thanks Peter, Mario, Jens and others for your efforts! -
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I reckon more than 1700 POTY's (kits) have been made. So there is potential activity enough. Furthermore there must be an RF incentive (i.e. make stuff for 2.4 GHz narrow band) to become active on the NB transponder. Making stuff for 2.4 GHz uplink seperates boys from men ; -)
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I made FT8 QSO's with no issues. When you set your (Windows) time properly with rsNTP (google on it) and you're stable enough, and you have clear audio, it works flawlessly.
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SP3OSJ Sorry to post this feedback here, but when I listen to your GPS stabilized RX (see YouTube movie) in relation with the beacon I hear unacceptable drift. It is not a steady tone and I hear too much phase noise (the tone is 'raw' and not clear).
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DF2HF: be sure that the braid of the semi rigid is well grounded! See points of interest below: