![Found these rca 5692 red base tubes in an old oscilloscope . Tested at 75%. I don't have anything to put Them in, yet, but maybe later down the road I will. Found these rca 5692 red base tubes in an old oscilloscope . Tested at 75%. I don't have anything to put Them in, yet, but maybe later down the road I will.](https://preview.redd.it/k4lcxq829rh11.jpg?auto=webp&s=cea8b1c22e7362e50cbcb63339d2d8c4fa193571)
Found these rca 5692 red base tubes in an old oscilloscope . Tested at 75%. I don't have anything to put Them in, yet, but maybe later down the road I will.
![Matched Pair: Raytheon 5691 Vacuum Tube Red Base Black Plates Support Rods Manufactured by RCA Matching Date Codes - Etsy Canada Matched Pair: Raytheon 5691 Vacuum Tube Red Base Black Plates Support Rods Manufactured by RCA Matching Date Codes - Etsy Canada](https://i.etsystatic.com/7035969/r/il/02e7fe/1219454932/il_fullxfull.1219454932_9e5w.jpg)
Matched Pair: Raytheon 5691 Vacuum Tube Red Base Black Plates Support Rods Manufactured by RCA Matching Date Codes - Etsy Canada
![5691/6SL7GT RCA Red Base High Mu Twin Triode Tube. The red base 5691 is a premium 6SL7 made to last over 10,000 hours and produce low noise. We have a couple of 5691/6SL7GT RCA Red Base High Mu Twin Triode Tube. The red base 5691 is a premium 6SL7 made to last over 10,000 hours and produce low noise. We have a couple of](https://media.rfparts.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/5/6/5691_rca_1.jpg)