Phil, VK7JJ has written a set of very comprehensive articles describing the design of a wire antenna which operates well all the way up to UHF frequencies.  He wrote this in response to a question posed by ZL2BMH as to how best to do this.    He indicates the results he obtained using an RSP1A on frequencies ranging from from 7MHz up to 432 MHz. Click here to read the posts

Even if you are not an RSP owner, the SDRplay forum is becoming a very useful place to get help regarding SDR-related topics.  There’s a search facility enabling you to find answers to a huge variety of questions including real basic questions which newcomers need help to answer.  It’s a great place to ask questions too. Please note that newcomers posts have to be moderated, due to spamming threats – this means it can be a while before your question appears.  For even more interactive discussion, there’s the independent Facebook group with nearly 9000 members where you can get help and advice. To join that group, go to: https://www.facebook.com/groups/sdrplay