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theredhouseinn · 23rd Dec 2019, 2:44 pm

Hi Alan.
I might try crushing one to see if there is anything odd in it. I have a Philips stylus microscope so I may see something.
I have changed c116 for a 630v cap. I am reluctant to omit it as it is there for a reason, maybe to stop hf oscillation in the stage which could damage the o/p tx winding.
There were no sprague caps in mine. My set is an early one with the engraved front panel.
It also has a pre-set pot at the rear of the chassis marked R21, but there is no R21 in the component list.
The pot is in series with the cathode load res of the last if stage. the two leads that are bolted to the lamp case on the front panel short out the pot to chassis. So I am assuming that the two leads are for the S meter when fitted and the pot is the setting control for the meter.
john.

23rd Dec 2019, 2:44 pm	#107
theredhouseinn Hexode Join Date: Jan 2013 Location: Kelvedon, Essex, UK. Posts: 273	Re: RCA AR88D Comms Receiver. Hi Alan. I might try crushing one to see if there is anything odd in it. I have a Philips stylus microscope so I may see something. I have changed c116 for a 630v cap. I am reluctant to omit it as it is there for a reason, maybe to stop hf oscillation in the stage which could damage the o/p tx winding. There were no sprague caps in mine. My set is an early one with the engraved front panel. It also has a pre-set pot at the rear of the chassis marked R21, but there is no R21 in the component list. The pot is in series with the cathode load res of the last if stage. the two leads that are bolted to the lamp case on the front panel short out the pot to chassis. So I am assuming that the two leads are for the S meter when fitted and the pot is the setting control for the meter. john.