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Re: Antenna input socket

Posted: Tue Sep 08, 2015 5:46 pm
by ChuckG
I'm new to SDR, and have an RSP on the way which is currently sitting in San Francisco according to Royal Mail. Have a question about the antenna connector on the unit. The forum posts here talk about type-F and others, and the tech specs online state "Single SMA RF connector." Will need to order connectors online as we don't much access locally other than type-F at Home Depot.
So the question: What RF connector is on the RSP's currently being shipped?


Re: Antenna input socket

Posted: Tue Sep 08, 2015 6:09 pm
by sdrplay
The RF connector on the RSP shipping now is SMA female.

Best regards,


Re: Antenna input socket

Posted: Wed Sep 09, 2015 6:01 pm
by ChuckG
Thank you for the quick reply. The RSP arrived yesterday (only a week from GB to southern Oregon). Works well once I realized that I had to click the 'Play / Start" button on the software.

Re: Antenna input socket

Posted: Wed Sep 16, 2015 7:08 pm
by skhreze
jon wrote:The technical team appreciated your comments here. They agonised for a long while on screening and decided that actually a plastic (unscreened) box was better.

The problem is that the biggest source of interference is the USB cable and the USB comms...putting in a screened box can often cause the USB interference to get “trapped” inside and generate more problems than it actually isolates. This very much depends on what PC you are using, desktop (well grounded) or laptop (not well grounded).

Probably good that you didn't connect the foil to the USB connector ground since this could inject USB noise to the front end but a lot of this depends on the frequencies of interest and your overall ground arrangement.

We'd welcome comments from others on this topic.

How about shield only analog part of circuit?


Posted: Fri Nov 06, 2015 9:16 pm
whats the optimum length of usb cable, or rather the maX? IS IT LIKE COAX FEED, THE SHORTER THE BETTER?

Re: Antenna input socket

Posted: Fri Nov 06, 2015 9:35 pm
sdrplay wrote:I can''t see what the problem is with the F-connector. It is low-loss to beyond 2GHz and it is simple to fit the plugs to the cable. OK, it''s 75-ohm, but that isn''t of great importance in this application. My only reservation about it is that it can sometimes be very frustrating when trying to screw the plug in on the back panel of a piece of equipment and the threads won''t engage or get crossed!


Re: Antenna input socket

Posted: Sat Nov 07, 2015 7:18 am
by micked
No, SMA connectors are always 50ohm.

Re: Antenna input socket

Posted: Sat Nov 07, 2015 8:17 am
by jon
The confusion comes from the fact that until May 2015 we provided a 75 ohm f-connector. Based on customer feedback we changed to the 50ohm SMA connector when we moved to the current black box casing.

Best regards, Jon

Re: Antenna input socket

Posted: Sat Nov 07, 2015 8:49 am
by DaveB
From the picture do I see that there is actually a miniature coax connector on the circuit board? If so what is it? I can the possibilty of getting a patch cable made with 'my' choice of bulkhead connector on the end. (I've got ver 1 with F-connector). Also it is nice to see an arrangement whereby the connector that interfaces to the outside world isn't integral to the board - less chance of the board getting damaged in the long term.

Also - you can get SMA to F connector adaptors quite easily.


Re: Antenna input socket

Posted: Thu Nov 19, 2015 7:03 pm
by tomboy

I bought an RSP a few weeks ago and would like to confirm that the RSP's antenna connector has the mechanical specs as shown on this page: (I'd like to be sure before I buy a matching plug and make myself an antenna cable.)