The article goes beyond the test, it describes specifically how no evidence has been produced: NO PROOF FOR THE RNA BEING OF VIRAL ORIGIN

Now the question is: What is required first for virus isolation/proof? We need to know where the RNA for which the PCR tests are calibrated comes from.

As textbooks (e.g., White/Fenner. Medical Virology, 1986, p. 9) as well as leading virus researchers such as Luc Montagnier or Dominic Dwyer state, particle purification — i.e. the separation of an object from everything else that is not that object, as for instance Nobel laureate Marie Curie purified 100 mg of radium chloride in 1898 by extracting it from tons of pitchblende — is an essential pre-requisite for proving the existence of a virus, and thus to prove that the RNA from the particle in question comes from a new virus.

The reason for this is that PCR is extremely sensitive, which means it can detect even the smallest pieces of DNA or RNA — but it cannot determine where these particles came from. That has to be determined beforehand.

And because the PCR tests are calibrated for gene sequences (in this case RNA sequences because SARS-CoV-2 is believed to be a RNA virus), we have to know that these gene snippets are part of the looked-for virus. And to know that, correct isolation and purification of the presumed virus has to be executed.

Hence, we have asked the science teams of the relevant papers which are referred to in the context of SARS-CoV-2 for proof whether the electron-microscopic shots depicted in their in vitro experiments show purified viruses.

But not a single team could answer that question with “yes” — and NB., nobody said purification was not a necessary step. We only got answers like “No, we did not obtain an electron micrograph showing the degree of purification” (see below).

We asked several study authors “Do your electron micrographs show the purified virus?”, they gave the following responses:

Study 1: Leo L. M. Poon; Malik Peiris. “Emergence of a novel human coronavirus threatening human health” Nature Medicine, March 2020

Replying Author: Malik Peiris

Date: May 12, 2020

Answer: “The image is the virus budding from an infected cell. It is not purified virus.”

Study 2: Myung-Guk Han et al. “Identification of Coronavirus Isolated from a Patient in Korea with COVID-19”, Osong Public Health and Research Perspectives, February 2020

Replying Author: Myung-Guk Han

Date: May 6, 2020

Answer: “We could not estimate the degree of purification because we do not purify and concentrate the virus cultured in cells.”

Study 3: Wan Beom Park et al. “Virus Isolation from the First Patient with SARS-CoV-2 in Korea”, Journal of Korean Medical Science, February 24, 2020

Replying Author: Wan Beom Park

Date: March 19, 2020

Answer: “We did not obtain an electron micrograph showing the degree of purification.”

Study 4: Na Zhu et al., “A Novel Coronavirus from Patients with Pneumonia in China”, 2019, New England Journal of Medicine, February 20, 2020

Replying Author: Wenjie Tan

Date: March 18, 2020

Answer: “[We show] an image of sedimented virus particles, not purified ones.”

I clicked the NIH link you provided. I cant find where they explain the process they used for isolation/purification