SRG uses a few different boards for tone decoding. Some of the remote (80) receivers use the stock micor PL deck (and reed) while others use what ever was available at the time of construction. Most of the control point uses the Communications Specialist brand, the TS-32 model of decoder. To further assist you in understanding this product, below are some spec sheets.
Here's a little tid-bit to be aware of. In the Yaseu manual for the FT-991 on page 94 shows how to program that radio for CTCSS operation. Paragraph 3 talks about the mode. You need to set it at "ENC", which means to encode (your transmit) the tone. Also if you notice the frequency example shown in the radio is a very poor example, since some links and other specialized stations are around 446.200 MHz. Awareness of what frequencies to test with would be best to use.
Back to SRG tech page