Pye Black Box howls when switched on - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

julie_m · 30th Oct 2017, 9:43 pm

I am away from home right now and can't show you a photo of my test setup, but the basic idea is to use an MP3 player as a signal source to test the operation of the amplifier by connecting the leads that would have used to have gone to one headphone, to the amplifier input instead of the pickup cartridge.

Edward Huggins · 31st Oct 2017, 11:31 am

Not being sure of the output level (mV) from your MP3 player, bear in mind that this might overload the amplifier. Using the Black Box's cartridge will match the amp and give the best basis for a test.

30th Oct 2017, 9:43 pm	#21
julie_m Dekatron Join Date: May 2008 Location: Derby, UK. Posts: 7,735	Re: Pye Black Box howls when switched on I am away from home right now and can't show you a photo of my test setup, but the basic idea is to use an MP3 player as a signal source to test the operation of the amplifier by connecting the leads that would have used to have gone to one headphone, to the amplifier input instead of the pickup cartridge. __________________ If I have seen further than others, it is because I was standing on a pile of failed experiments.

31st Oct 2017, 11:31 am	#22
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,340	Re: Pye Black Box howls when switched on Not being sure of the output level (mV) from your MP3 player, bear in mind that this might overload the amplifier. Using the Black Box's cartridge will match the amp and give the best basis for a test. __________________ Edward.