Problem with Gnuradio convolution encoder/decoder!

Hello,

I am trying to validate the correct CCSDS 27 encoder/decoder operation and put together the following configuration model:

1. A Random Source generator. generates a byte stream as the input to the CCSDS 27 encoder.

2. The CCSDS 27 encoder output is in byte, but the CCSDS 27 decoder input takes a float. So I use a "Uchar to Float" to connect the CCSDS encoder output to the CCSDS decoder input.

3. I connect binary sinks to collect the Random Source output and the output data from the CCSDS 27 decoder.

I compare the output of the two data sinks with a delay of 4 bytes in the output which is zero, the first 5 or 6 values agree, but after that no agreement, which leads me to believe there is a flaw in one or both blocks.

I have also tried some of the other CC encoder/decoder blocks and they failed.

  

I will appreciate any help or suggestions about the CCSDS 27 or the CC encoder/decoder in GNURadio.

Thank you!

Regards,
George