[amsat-bb] FT-991A Transmit Interference

[Patrick STODDARD (WD9EWK/VA7EWK)]

Zach,

The RF shielding isn't over components on the circuit board. The
inside of the RSP1A's plastic case has metallic paint which serves
as the shielding. From the same review you cited at:

https://www.rtl-sdr.com/a-review-of-the-sdrplay-rsp1a/

"Like the RSP2 the plastic case is now spray painted with metallic
paint on the inside. This works almost as well as a full metal
case to shield from unwanted signals entering directly through the
PCB, instead of through the antenna. We do still notice some
leakage making its way in through the coax shield, but it is
relatively minor with the shielding."

I have used my RSP1A to receive satellite downlinks, and have not
experienced issues as VA3ASE mentioned. I'm not using an FT-991 or
FT-991A, but use a variety of other radios (HTs, IC-2730A, FT-817,
TM-D710G) for the uplink side of my station with the RSP1A and a
tablet with HDSDR for the downlink.

73!




Patrick WD9EWK/VA7EWK
http://www.wd9ewk.net/
Twitter: @WD9EWK or http://twitter.com/WD9EWK





On Fri, Aug 3, 2018 at 3:50 PM, Zach Metzinger <zmetzing at pobox.com> wrote:

> On 8/3/18 10:07 AM, VA3ASE wrote:
>
> Zach my understanding is that the RSP1A is still shielded despite the
>> plastic box, but I actually have access to an RSP2pro in a metal case that
>> I can try out as well. I've never heard of a USB EMI filter before, I'll
>> look into that. I'm using a quality TrippLite USB cable with molded chokes
>> at each end.
>>
>
> Hello Alex,
>
> Based on the pictures shown in the review located at the following URL,
> there does not appear to be any shielding over any RF component.
>
> https://www.rtl-sdr.com/a-review-of-the-sdrplay-rsp1a/
>
> --- Zach
> N0ZGO
>
>