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Heatercathodeshort · 17th Dec 2017, 10:02 am

The alignment should be OK unless it has been previously fiddled. It will not drift on it's own.

Sound problems are usually due to reduction in value [eventually ending in a burn up] of the resistors associated with the EH90 AF amp 405/discriminator FM valve.
R73 18K R71 5.5K R69 180ohm. This fault will cause a very heavy drain across the HT line.

Other than this a conventional check of the output stage PCL84 and if distorted at low volume, the loudspeaker. J.

17th Dec 2017, 10:02 am	#67
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Nearly a Sobell 1000 and 2000 DST!! The alignment should be OK unless it has been previously fiddled. It will not drift on it's own. Sound problems are usually due to reduction in value [eventually ending in a burn up] of the resistors associated with the EH90 AF amp 405/discriminator FM valve. R73 18K R71 5.5K R69 180ohm. This fault will cause a very heavy drain across the HT line. Other than this a conventional check of the output stage PCL84 and if distorted at low volume, the loudspeaker. J.