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FERNSEH · 8th Nov 2019, 2:38 pm

Hi Mick,
Is that a transistor UHF tuner? Yours is the later version of the Thorn dual standard chassis. In the first versions the output from the UHF tuner was sent straight to the IF board, the result vas very poor performance on 625. With the 850 the signals from the UHF tuner are further amplified by selecting a position on the VHF tuner. Only disadvantage if my memory serves me was that you have the ritual of selecting to the 625 line standard by the switch on the cabinet left side and then selecting "UHF" on the VHF tuner. Customers didn't like that very much.
Actually for the early dual standards sets a little transistor IF amplifier was made available from the BRC service department. Plugged into socket SKT304.
Watch for bad capacitors in the frame timebase. These are plastic cased components but they still can go leaky.
Nice compact cabinet.

DFWB.

8th Nov 2019, 2:38 pm	#5
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Marconi 4610. Thorn 850. Hi Mick, Is that a transistor UHF tuner? Yours is the later version of the Thorn dual standard chassis. In the first versions the output from the UHF tuner was sent straight to the IF board, the result vas very poor performance on 625. With the 850 the signals from the UHF tuner are further amplified by selecting a position on the VHF tuner. Only disadvantage if my memory serves me was that you have the ritual of selecting to the 625 line standard by the switch on the cabinet left side and then selecting "UHF" on the VHF tuner. Customers didn't like that very much. Actually for the early dual standards sets a little transistor IF amplifier was made available from the BRC service department. Plugged into socket SKT304. Watch for bad capacitors in the frame timebase. These are plastic cased components but they still can go leaky. Nice compact cabinet. DFWB.