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FERNSEH · 10th Oct 2015, 10:34 am

Hi John,
even after replacing the short circuit AGC filter capacitor C134 (which was an LCR make) the vision AGC system was still not working as well as it should. The contrast control did not reduce the picture contrast down to an acceptable level. Replacing the PCC84 RF amplifier improved matters considerably, the valve had a grid to cathode leak. Finally, after replacing the M3 AGC delay diode the AGC system is working as the designer intended to should. This very sensitive receiver can handle very strong signals without any intermodulation effects.
Imagine what this set would have been like if it had been equipped with frame grid valves? The ultimate 405 dx receiver.

DFWB.

10th Oct 2015, 10:34 am	#44
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Ferguson 247T: huge console TV set. Hi John, even after replacing the short circuit AGC filter capacitor C134 (which was an LCR make) the vision AGC system was still not working as well as it should. The contrast control did not reduce the picture contrast down to an acceptable level. Replacing the PCC84 RF amplifier improved matters considerably, the valve had a grid to cathode leak. Finally, after replacing the M3 AGC delay diode the AGC system is working as the designer intended to should. This very sensitive receiver can handle very strong signals without any intermodulation effects. Imagine what this set would have been like if it had been equipped with frame grid valves? The ultimate 405 dx receiver. DFWB. Last edited by FERNSEH; 10th Oct 2015 at 10:44 am.