Portsdown 2019

The 2019 Portsdown is significantly different to previous versions in that the system no longer uses the custom built Filter Modulator card which has been replaced with an off the shelf LimeSDR Mini.

The LimeSDR Mini plugs in to the Raspberry Pi USB port, preferably via a powered USB hub and produces an RF outut from ~ 30MHz to 4GHz.

Overall the LimeSDR Mini is similar in cost to the FM board as you no longer need an ADF4351 LO module and an LO filter PCB and is available from the BATC shop https://batc.org.uk/shop/limesdr-mini/

Portsdown 2018

If you would still like an FM board, we suggest you post on the wanted section of the forum - https://forum.batc.org.uk/viewforum.php?f=14 - or blank PCBs for home construction are available here - BATC shop item 10.

All the wiki information on previous version of Portsdown are available here...

Hardware System Diagram

Here is the latest system diagram. Note that only one of the displays is required; either the 3.5 inch or 7 inch and the digital variable attenuator is only required if you want fine (<3 dB steps) control over your PA drive levels. The Lime Gain control on the Portsdown can be used to set the coarse output level.

Building the system

The Portsdown 2019 uses the majority of the 2018 Portsdown hardware.

• Portsdown2019 hardware Detailed description of the Portsdown 2019 hardware and a shopping list of what you need to buy and where to buy it.
• Assembling your Portsdown How to put all the hardware together - you need to read this!
• Portsdown Displays Advice on what display to use with your Portsdown transmitter.

Portsdown 2019 Software

The Portsdown 2019 uses the same software as later versions of the Portsdown 2018 software and is based on the Rpi Stretch operating system.

• Portsdown 2018/2019 Stretch Software The latest and greatest software for the Portsdown and how to get a programmed SD card.
• Portsdown Jessie Software Detailed description of the older Portsdown software.
• Software capabilities and issues An up to date list is available here
• Updating your Portsdown Software How to update your Portsdown software to the latest version, with suggestions for troubleshooting updates.