Next Page RF Capture Guide

Previous Page Hardware Installation Guide

This is a sub-doc about ADC's & SDRs that can be used for the decode projects this list includes standardised and validated methods and workflows and new options.

You can help expand this list via posting on the Discord, Sub-Reddit or Emailing Harry directly.

The input frequency range required for most of the signals from HiFi to CVBS video is 1Mhz to 10Mhz at least, this can go upwards of 30Mhz for MUSE RF.

2msps = 1 Mhz of Bandwidth

So most archival class solutions today will be based around the 28-40msps minimum range sampling wise, of course this is wholly format dependent with HiFi RF requiring less then 10msps.

Other factors such as input LPF (low pass filters) makes common SDRs a very mixed viability for straight to file and onto decoding with ease.

CX Cards Doc

28.6msps 8-bit / 40msps 8-bit / 54msps 8-bit (upto 57msps on some cards)

FM RF capture via the CX Card method has been further improved with external amplifiers.

The off shelf go-to today is the Analog Devices AD8367 based boards using 3-5v:

Pot-less AliExpress Link / With Pot AliExpress Link / 4.5v AA Battery Holder / Wiki Setup Link

There is also other amplifiers available that are more fine tuned for FM capture with the CX Cards.

The newest is the vhs-rf-amp-ada4857 board by Rene Wolf using 12v.

Clockgen mod simplified wiki

• Software Defined Crystal Rate
• Hardware Synchronised Multi-Card Capture
• Hardware Synchronised Linear/Baseband Audio Capture

The most advanced mod available today, using an external crystal to generate the clock source we can have drift free capture with 2-4 CX Cards and audio feeds.

This allows duel channel video formats such as Betacam to be captured, or Video FM + HiFi FM + Linear for many other formats like VHS or Betamax.

Possible thanks to cxadc-clock-generator-audio-adc By Rene Wolf

External crystal timing via 2 additional PCB boards, a Jig with an SMA and Mainboard has allowed for under 50USD multi card sync, using 2 or more CX Cards alongside a extra input for synchronised Linear/Reference audio capture also has a extra input for headswiching timing signals.

• Raspberry Pi Pico as the interface and control board.

• Adafruit Si5351A for generating the shared clock source with 5 potential inputs.

• PCM1802 ADC for L/R input Linear/HiFi audio capture.

Audio inputs and head switch input is on a dedicated bracket you can 3D print.

Clock Speed & Audio is controlled by Alsamixer, and synchronised capture via script.

DomesDay Duplicator Docs

40msps 10-bit

DE0-Nano FPGA / FX3 USB 3.0 Board

• TI ADS825 ADC
• OPA690 OP-AMP
• Selectable 4 Position DIP gain control

Used for HiFi-Decode & RTL-SDR Decode.

Pictured Order: TNC Male to SMA Male / TNC Female to SMA Male / BNC Male to SMA Male / BNC Female to SMA Male / Nooelec RTL-SDR v5

RTLSDR Page

Formerly called adc_usb3 / SMIRF - Simultaneous Multi Input RF Capture. - DD86 Discord

GitHub GitHub Wiki

PCB: 20-30USD / Parts 100-120USD

Mainboard + FX3 USB 3.0 board

PCBway Order Link

Features

• Off shelf FX3 USB 3.0 board (same as DdD)
• External Clock Source Output
• 6 Extra Aux inputs for audio ADC modules etc
• Duel ADC / Duel Input
• Physically adjustable input filters
• 12-Bit, 20/40/65msps sampling
• AD8138 Driver, Op-Amp / SN74ls541 Buffer / AD9235 ADC

LTC2208 ADC - 16-Bit, 130Msps

CYUSB3014

USB 3.0

Limited capture software support

Taredown & Performance

Info / AliExpress (Global/MSRP) / Amazon UK / Amazon US

Limited Linux Support, developing slowly, working windows support more testing and testers required.

Original / AliExpress Clone

The original has been used by several members for testing but the clones that are under half the price.

RSP1 RF Capture & Decoding

8-bit 20msps ADC

There is two main physical versions, the physical multi input and the compact DIP switch configurable ones.

AliExpress Compact DIP Bare

AliExpress Compact DIP With Shell

AliExpress Physical Breakout

Extensive Docs

https://revspace.nl/Msi2500SDR

https://www.jotrin.com/product/parts/MSI001

Follow The Original Discussion On Discord

07.08.2023 Continued Discussion On Discord

Notes

The msi2500 is a variable bit (8 to 14 bit) ADC and DSP with USB interface. (See: msi2500-BlockDiagram.jpg)

The result is: a range from 10 kHz to 1 GHz (with a hole at 250-400 MHz) a bandwidth of up to 10 MHz,

MSPS from 2 to 6 MHz (14-bit) MSPS from 6 to 8 MHz (12-bit) MSPS from 8 to 9 MHz (10 bits) MSPS from 9 to 10 MHz (8 bits)

With a SNR of 60 dB.

One of the most early open-source ADCs eyed by the members of the decode projects during the early hifi days.

GitHub / CrowdSupply / Discord Server

HanTek SDR

First Discord Notation

PSO2020 Wiki / AliExpress

8-bit 30MSPS

Cypress FX2 / AD9288

Software;

sigrok-firmware-fx2lafw with librtlsdr modified for continuous write mode.

This can also apply to the 6022BE a duel input BNC Oscilloscope.

Next Page RF Capture Guide

Previous Page Hardware Installation Guide