Difference between revisions of "Portsdown 2019"
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===Specification=== | ===Specification=== | ||
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===System Diagram=== | ===System Diagram=== | ||
Revision as of 17:14, 4 February 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.
The LimeSDR Mini is available from the BATC shop https://batc.org.uk/shop/limesdr-mini/ - 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.
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.
Specification
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.
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.