UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

G6FGPDAVE · 6th Apr 2012, 6:08 pm

Hi,

I've just assembled two of these JLH 10 watt class A classics (1969 - not quite antique!) but have not tried them yet as I need to source suitable heatsinks.

My main worry is the ST 2N3055 devices; they are not printed as I would have expected; the printing is fuzzy and looks as tho' it is on a layer of silver paint rather than directly on to the metal can. Scraping the paint off doesn't reveal any markings underneath but the surface of the can looks as though it's been scrubbed.

QUESTION Are these devices fakes? If so are they as good for this application as the pukka transistors?

6th Apr 2012, 6:08 pm	#29
G6FGPDAVE Retired Dormant Member Join Date: Sep 2011 Location: Newcastle upon Tyne Posts: 1	Re: JLH Class 'A' Amplifier Hi, I've just assembled two of these JLH 10 watt class A classics (1969 - not quite antique!) but have not tried them yet as I need to source suitable heatsinks. My main worry is the ST 2N3055 devices; they are not printed as I would have expected; the printing is fuzzy and looks as tho' it is on a layer of silver paint rather than directly on to the metal can. Scraping the paint off doesn't reveal any markings underneath but the surface of the can looks as though it's been scrubbed. QUESTION Are these devices fakes? If so are they as good for this application as the pukka transistors?