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SteveCG · 10th Jul 2019, 11:32 am

A postscript thought:

Both the Roberts radios have a socket for an external power supply (9 volts). This, I note, has a -ve centre pin. This is rather unusual as most externally powered devices have a +ve centre pin. I just wonder whether an incorrectly polarized psu has been used and has damaged/taken out the TDA1220B chip?

10th Jul 2019, 11:32 am	#2
SteveCG Nonode Join Date: Jun 2009 Location: Herefordshire, UK. Posts: 2,495	Re: TDA 1200B AM/FM radio chip A postscript thought: Both the Roberts radios have a socket for an external power supply (9 volts). This, I note, has a -ve centre pin. This is rather unusual as most externally powered devices have a +ve centre pin. I just wonder whether an incorrectly polarized psu has been used and has damaged/taken out the TDA1220B chip?