SincroSauro

un ricevitore HF cosi piccolo da poterlo custodire comodamente tra le fauci

• piccolo
• economico
• a basso consumo (<100ma)
• a bassa tensione (3.3v)

VFO

Basta un Ondeggiatore!

Filtro di ingresso

set di filtri passa basso LC commutabili dimensionati per reggere in futuro un piccolo trasmettitore (<5W)

• http://www.gqrp.com/technical2.htm

i sistemi di switch praticabili sono:

• commutatore meccanico: problemi di cablaggio e di contatti
• diodi PIN: consumano molto, non sembrano esistere per 3.3v
• microrelays DIP: consumano abbastanza e hanno problemi di contatto (a meno di non implementare il 'DC wetting', non sembrano esistere per 3.3v
• FET discreti:
  • http://www.n5ese.com/tr_switch.htm
  • ci sono pochi FET con Vgth < 3.3v che lavorino bene ad alta frequenza:
    • http://www.st.com/web/catalog/sense_power/FM100/CL824/SC1164/PF253858
• Digital Bus Switch: hanno una Ron non indifferente, non reggono segnali molto forti, lavorano malino a 3.3v
  • http://www.m0rjd.co.uk/bus-switches.html
  • http://martein.home.xs4all.nl/pa3ake/hmode/IF_switches.html
• Analog FET switch
  • gira voce che quelli che operano a 3.3v hanno una pompa di carica sul gate che fa rumore. verificare.
  • cose del genere possono avere senso? http://www.ti.com/general/docs/lit/getliterature.tsp?baseLiteratureNumber=slyb125
  • http://www.ti.com/product/ts3a4751 0.9-Ω LOW-VOLTAGE SINGLE-SUPPLY QUAD SPST ANALOG SWITCH
  • http://www.maximintegrated.com/datasheet/index.mvp/id/3351 MAX4734 0.8Ω, Low-Voltage, 4-Channel Analog Multiplexer
• Amp Buffer integrati
  • Una via (solo rx)
  • ABA32563 http://www.avagotech.com/pages/en/rf_ics_discretes/rf_ics/silicon_amplifiers_gain_blocks/aba-32563/ reperibili a poco, bevono 37ma

letture:

• http://www.skyworksinc.com/downloads/press_room/published_articles/MPD_062009.pdf
• http://www.skyworksinc.com/downloads/press_room/published_articles/MPD_052009.pdf
• http://www.m0rzf.co.uk/softrock7/

Topologia

• Conversione diretta
  • DSB
• Weaver
  • Quadratura -> low pass -> quadratura
  • http://www.hanssummers.com/weaver.html
• Quadratura

Letture:

• http://homepage.ntlworld.com/johngduffy/Project/Chapter2.htm#Multi
• http://stor1.nonoo.hu/hamdsptutorial/weavermethod.pdf

Miscelatore

Gilbert-cell

Una cella di gilbert implementata con un array di bipolari: regge piu di un mosfet dual-gate e consuma meno di un ring di diodi

HFA3101 http://www.intersil.com/en/products/amplifiers-and-buffers/transistor-arrays/transistor-arrays---gilbert-cell-uhf/HFA3101.html

DGMOS

http://sm0vpo.com/blocks/mixers-1.htm

ma sembrano introvabili a 3.3

Commutativo

http://www.oe1ira.at/sl/mix.html

http://g4oep.atspace.com/mixers/notes_on_the_basic_operation_of_.htm

http://www.m0rjd.co.uk/bus-switches.html occhio al bias

Switch integrati

• http://www.ti.com/product/ts3a4751 0.9 Ohm Low-Voltage Single-Supply Quad SPST Analog Switch tON = 14 ns, tOFF = 9 ns, essendo spst bisogna avere due segnali LO complementari
• http://www.ti.com/product/ts5a623157 Dual 10-Ohm SPDT Analog Switch With Undershoot/Overshoot Voltage Protection
• http://www.ti.com/product/ts5a23159 1-Ohm Dual SPDT Analog Switch 5 V/3.3 V 2-Channel 2:1 Multiplexer/Demultiplexer
• http://www.analog.com/en/switchesmultiplexers/analog-switches/adg711/products/product.html

Bilanciati

1. http://www.sm0vpo.com/_visitors/blocks/cmos-mix.htm non si capisce come possa funzionare
2. http://home.snafu.de/graff/sbt40.pdf rf splittata a condensatori, LO split a porte logiche
3. http://yu1lm.qrpradio.com/HF%20SDR%20RECEIVER%20CW-SSB-DRM%20YU1LM.pdf
   • RF sbilanciata
   • LO + !LO
   • OUT bilanciato
   • si puo reimplementare con un singolo SPDT
4. http://www.qrp.pops.net/K7LR-Memorial.asp
   • RF bilanciata (a trasformatore)
   • un dual spst
   • OUT sbilanciato
   • simile a https://lz3nf.wordpress.com/2013/07/25/280/
5. http://www.qsl.net/aa9gg/proj/dc40xx_ugly/dc40xx_ugly.htm
   • Praticamente il n 3 bilanciato
   • RF bilanciata (trasformatore)
   • 74hc4053 3xSP2T
   • OUT bilanciato
6. http://www.m0nka.co.uk/?page_id=466
   • RF bilanciata a trasformatore
   • LO + !LO
   • Out sbilanciato

H-mode

http://www.phonestack.com/farhan/mixermusings.pdf

ma uscire in audio da un trasformatore e' grigia

• http://martein.home.xs4all.nl/pa3ake/hmode/fsav430.html ma l'fsav430 pare semiintrovabile
• http://g4oep.atspace.com/mixers/notes_on_the_basic_operation_of_.htm#The%20QRSS%20Mixer. questo ha l'uscita audio
• http://www.qsl.net/g3oou/solidstatecircuits9.html con due SPDT
• magari in versione 2T
  • http://martein.home.xs4all.nl/pa3ake/hmode/2t-hmode.html
  • http://www.arifidenza.it/forum/topic.asp?TOPIC_ID=81490

QSD

ma ci vuole il LO in quadratura o un accrocchio

• http://kc.flexradio.com/KnowledgebaseArticle50193.aspx SDR1000
• http://martein.home.xs4all.nl/pa3ake/hmode/IF_detector_qsd.html

• http://www.ti.com/lit/ds/symlink/sn74cb3t3253.pdf
• http://www.itsrainingelephants.com/blog-archives/tag/adg704/ http://www.analog.com/en/switchesmultiplexers/multiplexers-muxes/adg704/products/product.html

Altri mixer:

• http://www.analog.com/en/rfif-components/mixersmultipliers/ad8343/products/product.html ma 5v
• http://www.analog.com/en/rfif-components/mixersmultipliers/ad607/products/product.html basso consumo, if 400khz-12mhz, demod quadratura

Diplexer

sul diplexer che segue il mixer si gioca buona parte della dinamica del ricevitore

http://www.qrp.pops.net/dip2.asp

• http://www.qrp.pops.net/dip_sup.asp
• http://www.tuberadio.com/new.html
• http://www.vk6fh.com./vk6fh/DIPLEXER%201.htm
• http://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/radcom/1991/04/page39/
• http://www.qsl.net/g3oou/mixerterminations.html
• http://www.seboldt.net/k0jd/r2pamp.txt

Amplificatore audio

preamp e filtro LP:

• LVM772 http://www.ti.com/product/lmv772
• TL974 http://www.ti.com/product/tl974
• OPA365 http://www.ti.com/product/opa365 2.2V, 50MHz, Low-Noise, Single-Supply Rail-to-Rail Operational Amplifier
• ADA4692-2 http://www.analog.com/en/all-operational-amplifiers-op-amps/operational-amplifiers-op-amps/ada4692-2/products/product.html Low Power, Wideband, Low Noise, Rail-to-Rail Output, Dual Op Amp

PA:

• TPA2005D1 https://focus.ti.com/docs/prod/folders/print/tpa2005d1-q1.html
• LM4667 http://www.ti.com/product/lm4667
• SSM2305 http://www.analog.com/en/audiovideo-products/audio-amplifiers/ssm2305/products/product.html