The Airspy Mini sells for $114. Worth looking into.
73 Jim Barbre KB7YSY
On 6/16/2016 1:22 PM, Patrick STODDARD (WD9EWK/VA7EWK) wrote:
Hi, (name or call?)!
The inexpensive RTL-SDR dongles are a great way to get started with SDR receivers. For amateur satellite work, other than the ISS and maybe AO-85, they have a couple of significant drawbacks...
- These dongles were designed to be TV receivers, working with
signals much stronger than we have from our satellites or even the ISS ham station.
- These dongles lack front-end filtering. This means that there could
be a strong signal near you that swamps the receiver that wipes out what you're trying to hear. If you are trying to work satellites full-duplex, it is possible that your transmitter will shut down the dongle until you end your transmission. This was a problem I experienced early on when I tried using one of these dongles as my downlink receiver, and quickly moved on to something else.
Unfortunately there isn't anything in the middle ground between these dongles and devices like the SDRplay (sold by HRO in the US for $149) or the FUNcube Dongle Pro+ (sold by its UK manufacturer for around $200 depending on exchange rates, which includes FedEx next-day shipping from England to most addresses in the continental USA). Both of these devices do well as the downlink receiver for working satellites. Both come with front-end filtering that the RTL-SDR dongles lack, and still have sensitive receivers. The SDRplay has a low-noise amplifier that is engaged when receiving at VHF or higher, but you can reduce the amount of gain from the built-in LNA. For my work, I keep that gain reduction value set to 0, so I have maximum gain to hear the downlinks.
Good luck, and 73!
Patrick WD9EWK/VA7EWK http://www.wd9ewk.net/ Twitter: @WD9EWK