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FERNSEH · 31st Dec 2017, 4:18 pm

From the 1958 Mullard Maintenance Manual, page 109.
The ECL80 triode-pentode:

Combined triode and output pentode primarily designed for use in television receivers with the triode as a frame blocking oscillator and the pentode as a frame output valve. Other applications include the use of the triode as a line blocking oscillator, AF voltage amplifier or in multivibrator circuits and the operation of the pentode as an audio output valve or a synchronising pulse separator.

No mention of the application of the valve as a mixer-oscillator in television receivers. Another TV receiver that employed the ECL80 as the Band 1 frequency changer was the Peto-Scott TV1422, although later versions of this 1953 set employed the PCF80.
In the Philips 1446U series TV receivers an ECL80 was employed in the second stage of the 8.5Mc/s sound IF amplifier. Triode section employed as the AF amplifier. PL82 output.

DFWB.

31st Dec 2017, 4:18 pm	#39
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Vintage Television Technology. From the 1958 Mullard Maintenance Manual, page 109. The ECL80 triode-pentode: Combined triode and output pentode primarily designed for use in television receivers with the triode as a frame blocking oscillator and the pentode as a frame output valve. Other applications include the use of the triode as a line blocking oscillator, AF voltage amplifier or in multivibrator circuits and the operation of the pentode as an audio output valve or a synchronising pulse separator. No mention of the application of the valve as a mixer-oscillator in television receivers. Another TV receiver that employed the ECL80 as the Band 1 frequency changer was the Peto-Scott TV1422, although later versions of this 1953 set employed the PCF80. In the Philips 1446U series TV receivers an ECL80 was employed in the second stage of the 8.5Mc/s sound IF amplifier. Triode section employed as the AF amplifier. PL82 output. DFWB.