OK, clear, I tried a MB506 (/64) with an ADF4351 but it didn't work. For the 1650.5 variant it took the 825.25 spur... too much hassle to filter it. I found another prescaler .. which works ... ; -)
MY QO100 SETUP
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Yeah, depending on the settings the ADF can create harmonics and spurs which these prescalers don't understand. Bear in mind, at the time these prescalers were developed .... there were no ADF's ; -)
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Hi, I use an other frequency generator that has very low harmonics , it produces 25 MHz but LNB did not work as the produced signal was square after the division...
Also for RX/TX at 28 project I try a ADF4350 but it does not lock. I try also the same settings as done before with no luck. It seems that is defected.
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Where do you use the ADF4350 for, to produce 404 MHz LO (432 - 28 MHz) ?
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Hi Remco, for 402(430-28) and 711(739-28). It read a pin and when changed by PTT it resend data.
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Hi, a harmonics frequency generator with a fundamental frequency of 125 MHz which generates f up to 10 GHz is build driving a SBB5089 MMIC with 2.2 pF from a 4 pin oscillator.
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Hi the expected ADF4350 arrived but not working. It was going at nearby frequencies and when I touch some components the lock led was light for a while and then stop. Also the frequency was going at higher frequencies when I touch the +5V and some pins. The conclusion was that the phase comparator was not driving the VCO. This it was and a jumper cable replaces the cut PCB.So it is repaired and 28 MHz Tx&Rx can go on !!!
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Hi,
The driver from ADF4350 for 2 * SBL1 (one for Rx and one for Tx) is finally build. It is a SBB5089 (20 dB 4 GHz !!! 20 dBm) and a splitter, driving two 4 dB attenuators before the 2*SBL1. The MAV11 that I plan to use did not give enough gain (only 12 dB) as the ADF4350 was giving 0 dBm maximum at 402 & 711 MHz and the signal produced after the MAV11 and division was less than +7dBm required by SBL1. Now aftrer the attenuators is about +10dBm which gives better performance to SBL1.
The first QSO with the 28 MHz If and IC735 is done with Alex SV8QG. Extracting from the ADF4350 the TCXO and driving it with GPSDO 25 MHz out, I can finally transmit at the same frequency I receive. I have S 1-1.5 noise level and the beacons are S 6-6.5.
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Hi, updated block diagram.
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Hi, the transverter from 28 to 739/430 is put in to a box. One eBay SMA female chassis connector was defective (the center pin was missing !!!).
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Keep up the good work George.
PS Don't forget to make some QSO's ;; -)
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2N2222 is also TUN ; -)
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2N2222 is also TUN ; -)
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I am a left handed (and forced ambidexter .. e.g. with scissors), so I am used to think 'different' (i.e. right handed) ;; -)
After all, a BC547 is not a 2N2222 ; -) -
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Kan dat bord onder de 35Mhz??? (weer een hack toepassen??)
Voor output op 70Cmtr moet het lo sig toch 25.78...Mhz...zoals de xtalfilter...
That's probably why Remco used a upb571 prescaler, to reduce the 4351 output to 25.78 MHz
Other question - the 4351 doesn't work without being programmed, so you need an aatiny/pic to send it it's programming data, no?
Also, why the capacitance multiplier? If you supply 13V, then I'd think you use the stabilizer in the LNB and I don't see the benefit if the capacitance multiplier?