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DMcMahon · 22nd Jan 2020, 1:59 pm

Electronics chassis all fused up and powered up, looks OK so far, no bangs, smoke or fireworks. Snubbers OK but of course no inductive motor load yet as transport chassis not fitted yet.

24 vdc supply good at 31 volts 30mV 100Hz mains ripple off load, dropping down to around 26 volts (not a regulated voltage) on relay load.

Main DC HT supply good at 262 volts with 30mV 100Hz ripple (seems very low for HT ripple).

Been checking the various DC voltages to the valves and there appears to a problem with the ECC 81 not seeing any anode voltages, am struggling to find resistor R40 (5kohm) that feeds the main HT to the second anode etc,

This is the valve that I had a lot of trouble with when replacing 2 paper capacitors due to birds nest of components/wires around the valve, so checking it out further to see if anything has been disturbed incorrectly and where R40 has got to.

Magic Eye valve EM 71 lighting up, a bit dim maybe but probably normal.

22nd Jan 2020, 1:59 pm	#87
DMcMahon Dekatron Join Date: Apr 2019 Location: Worthing, West Sussex, UK. Posts: 6,603	Re: Grundig TK 819 Any Useful Info Electronics chassis all fused up and powered up, looks OK so far, no bangs, smoke or fireworks. Snubbers OK but of course no inductive motor load yet as transport chassis not fitted yet. 24 vdc supply good at 31 volts 30mV 100Hz mains ripple off load, dropping down to around 26 volts (not a regulated voltage) on relay load. Main DC HT supply good at 262 volts with 30mV 100Hz ripple (seems very low for HT ripple). Been checking the various DC voltages to the valves and there appears to a problem with the ECC 81 not seeing any anode voltages, am struggling to find resistor R40 (5kohm) that feeds the main HT to the second anode etc, This is the valve that I had a lot of trouble with when replacing 2 paper capacitors due to birds nest of components/wires around the valve, so checking it out further to see if anything has been disturbed incorrectly and where R40 has got to. Magic Eye valve EM 71 lighting up, a bit dim maybe but probably normal.