Fiction written in the community based on one television series has been printed in pale blue ink on yellow paper, which photocopies as a blank page. Editors and authors would release the work only to people they knew, and then only after the purchaser had promised not to pass the work any further. Secondary readers - those known to the purchasers but not to the editors or writers - could be given the option to read the work in the home of the purchaser, but generally could not receive full access until they became well known in the fan group.

Fans of another television show circulate their fiction almost entirely through underground photocopy. Stories created in this group are passed anonymously, or with pseudonyms. Members of the community may find out who created specific stories and will know who creates the community as a whole, but participants guard their outside identities.

Camille Bacon-Smith, writing about pre-internet fanfic communities in her book Enterprising Women: Television Fandom and the Creation of Popular Myth
(via surrexi)

Let’s see if I can remember the fandoms CBS is referencing

The first is….Starsky & Hutch RPS? (no, wait that was The Purple Pages) - named because they were printed on purple paper. There was a Starsky & Hutch gen and slash zine that was printed in blue ink on red paper: Pushing The Odds. You can see images of the zine here as well. So I am drawing a blank on the blue ink/yellow paper fandom.

The second is The Professionals a UK based crime show. The writer is describing the Circuit which began in the UK and then spread worldwide (mainly US and Australia). 

From Fanlore, the fan run non-profit wiki

“By the late 1980s, Professionals fandom had begun to offer zines, but most of the fiction was still on the “circuit,” which by now had been gathered together in the Circuit Library.[1] ….. The US library was initially called “The Hatstand Press Lending Library,” but it too came to be known as the “Circuit Library.[3] While the US and UK circuits had significant overlap, time, distance and the informal nature of distribution meant there were differences in what was included in the circuit library in each country. In addition, in the early days of the fandom there was some resistance to sharing UK circuit stories with the Americans. According to one UK fan, distribution of stories to the US was slow to start. There were tensions between some British and US fans regarding the quality of the US written fiction, the inclusion of Americanisms in US fiction, and the "right” of those not living in the UK to write about a UK show. To ease tensions, some UK fans increased the number of copies they mailed to the US.[4]

The majority of circuit stories were slash and were passed from fan to fan either in person or through the mail. The stories were written under pseudonyms…..Copies were originally printed using typewriter carbon paper but as the number of UK readers grew fans mailed their stories to a UK fan who had access to a photocopier at work.[5] As an interesting side note: UK circuit stories were printed on A4 paper so when the stories were copied in the US onto smaller letter sized paper, the titles and the author names were sometimes cut off. Fans would write what they thought were the titles and names in the margins with the info scratched out and corrected by subsequent readers. Pages grew more and more faded after multiple copying and, on occasion, the top and bottom lines were cut off during US photocopying. Some of these factors led to the creation of the US electronic circuit library (see below).

In the early 1990s, the U.S. library had over 1,000 stories. You could order up to 10 stories at a time once a month. It cost $12 a year to join, plus mailing fees both ways. (At 10 stories a month, it would take about 10 years to read them all.) The library worked best when you worked in unison with a partner or two, so that fans could double, triple, or quadruple the amount of stories they could receive per month. Fans would photocopy the stories and bind them. These bound stories would often be lent locally to other fans in effect becoming their own mini-circuit library.”