Base abbreviations other than ACTGU in sequence file Short question:
where can I find what F and J and &lt; and - and 7 mean in a Sequence file?
Longer version:
I was looking at this sequence file I got from NCBI (it's an sra file? if that is the correct terminology) and I used the sratoolkit to print out a few spots
looking at them I expected to see ACGU (this was meant to be an RNA sequence), but what I see are like

AAFFFJJJFJJJJJJJJJJJJJJJJJJJJJFJJF&lt;JJ77AJJJJ-JJJJJFF7FA--F7FAJJ7&lt;AJ-FJA&lt;J&lt;JJFA&lt;&lt;77F-JJJJJJF&lt;JF&lt;7-FF-A-----A-77JJ7FJJF-FFFAJ&lt;&lt;-FJJFAJAFFAFFFFF&lt;7A7JFJJ7AAFFFJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJFJJJFJJJJJJJJJJJJAA&lt;JJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJJAAFFJJFJJJJJJJJJJJJJJFJ-FJF

Where can I find a reference to help me &quot;understand&quot; this?
I mean I assume - means missed or unknown? or is it meant to be already aligned and these are deletions?
I appreciate any pointer to get started. as you must have observed I am a total noob.
I got the file from: https://www.ncbi.nlm.nih.gov/sra/SRX8156420[accn]
Then I did a
 ./fastq-dump -X 5 -Z ERR4557575


Follow-up question:

Where do you look for the quality scores ranges and such, I guess as @winnie2k suggested I should convert this to FASTQ and make my life easier, but still wanted to understand the file better.
I usually convert SRA files to FASTQ before doing any further processing, but the tooling for converting SRA files is cumbersome.
To simplify things, I recommend you download the FASTQ file directly. The ENA currently has a nicer interface for doing these things. Here is a link to download the FASTQ files for the SRA sequencing run associated with the SRA experiment you are describing: https://www.ebi.ac.uk/ena/browser/view/SRR11588968
A description of the FASTQ format can be found here: https://en.wikipedia.org/wiki/FASTQ_format