UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Mullard 5-10 amplifier

G8HQP Dave · 18th Jun 2019, 4:49 pm

The 5-10 has quite high gain from the input grid to the LTP anodes, and one of the anodes will be the same polarity as the input. Big caps or poor layout can provide enough capacitive feedback to tip things over the edge. In a 5-20 I built I had to insert a small screen to prevent this.

18th Jun 2019, 4:49 pm	#76
G8HQP Dave Rest in Peace Join Date: Sep 2008 Location: Solihull, West Midlands, UK. Posts: 4,872	Re: Mullard 5-10 amplifier The 5-10 has quite high gain from the input grid to the LTP anodes, and one of the anodes will be the same polarity as the input. Big caps or poor layout can provide enough capacitive feedback to tip things over the edge. In a 5-20 I built I had to insert a small screen to prevent this.