The search returned 2 articles:

  1. January 2020: Project: A low-voltage valve audio preamp by John Clarke, kits: Altronics kit K5192 (discontinued), PCBs: SC 01112191 [print issue] [online issue]
  2. January 2020: Project: A low-voltage valve audio preamp by John Clarke, kits: Altronics kit K5192 (discontinued), PCBs: SC 01112191, 3 shop items [print issue] [online issue]