UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Convert Vintage Valve Radio to Guitar Amp

ms660 · 13th Aug 2019, 10:53 am

(Trader sheet refs.)

The input impedance of the KB LR10 when switched to gram input is approx. 500kohm (R9) The gain can be increased by fitting a suitable capacitor across the audio output valves cathode bias resistor (R15) The bass response can be reduced by reducing the value of the audio output valves control grid coupling capacitor (C19)

C19 should be replaced anyways to prevent possible damage to the output valve and transformer etc due to electrical leakage of the said.

Lawrence.

13th Aug 2019, 10:53 am	#22
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Convert Vintage Valve Radio to Guitar Amp (Trader sheet refs.) The input impedance of the KB LR10 when switched to gram input is approx. 500kohm (R9) The gain can be increased by fitting a suitable capacitor across the audio output valves cathode bias resistor (R15) The bass response can be reduced by reducing the value of the audio output valves control grid coupling capacitor (C19) C19 should be replaced anyways to prevent possible damage to the output valve and transformer etc due to electrical leakage of the said. Lawrence. Last edited by ms660; 13th Aug 2019 at 11:04 am. Reason: Advisory addition.