Re: Pye 834
Below chassis no real surprises – the wax paper capacitors all looked original bar one and all bar one were leaky and were replaced. I did go to the extent of restuffing the 20uF electrolytic cathode decoupler on the TDD4 detector – not something I usually bother with but the case of the component was is such good cosmetic condition it seemed a shame to just bin it. I tested the valves on the VCM163 and while the TDD4, VP4B IF amplifier and the PenB4 AF output valves tested very good to excellent the DW4/350 rectifier and the triode part of the TH4B showed very low emission so I replaced both. I bought a couple of DW4/350 off eBay one of which was excellent. The Wireless Retailer & Broadcaster sheet showed the frequency changer as a TH4A. I did have one but, on account of a wooden spacer bar across the back of the set behind the valves, it was impossible to fit a TH4A because it is fatter than a TH4B so I stayed with the TH4B. When Ed’s transformer arrived I did some careful measuring because space was tight. The replacement was a drop-through type but I made up some brackets and utilised a spare mounting frame removed from another transformer which was exactly the right size, to mount it vertically. The rectifier was mounted on a canted paxolin board on top of the old transformer but when I removed the old transformer from the chassis I saw that there was an unused spare valve-holder hole in the chassis that had been partially obscured. By re-routing the screened cables to the volume control I was able to fit a B4 valve holder and so the replacement DW4/350 would just fit into the space envelope in front of the replacement transformer. I thought I was going to need to replace the five 6.3v 300mA pilot lamps with LEDs to save some current but Ed’s transformer was rated at 4v 6A. Total heater/lamps budget was 5.75A and so I left them in and didn’t use the LEDs.
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