Thread: Bush A.C.91
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Old 24th Feb 2018, 12:54 pm   #263
DonaldStott
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Location: Glasgow, UK.
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Default Re: Bush A.C.91

Earlier this week tim.norris mentioned " ...have not had problems with hum from heater wiring . is the screened wire to the cap of v3 the ebc 33 in good condition ,have you metred both the outer and inner wires through ? " I was so wrapped in possible issues with V4 that I forget I hadn't checked continuity through the co-axial cable running to the V3 top cap.

Guess what - I checked continuity and got the usual beep from the screen and then nothing from the inner conductor! Looking inside the V3 cap it was immediately clear that the inner conductor had snapped and was touching the middle of the valve cap - see attached picture! Thanks Tim! So looked out a new length of co-axial cable and replaced the existing - my goodness it's a tight fit.

Switched on the set, waited for the valves to heat up - no real hum and the radio literally blasted into life !!!


Can't believe that I now have stations on Short Wave, Long Wave and countless stations of Medium Wave - all at a very good volume but with lots of background noise. Really can't complain as the set is seriously alive for the very first time!

Thanks to everyone for their for their patience, help and support - don't know if I need to replace CL33 now?? I had to pluck up the courage to Post this update on the Forum as its a bit embarrassing but hopefully this may be of some help to others?

As David G4EBT reminded me "Just goes to show - it can often be the simplest of things that can lead you a merry dance."

Final tasks are related to what can be done with that residual background noise - am I expecting too much? I've removed all possible causes of interference from other sources?

Meantime I remembered that some "idiot" had inscribed deep scratches on the front and side (see attached picture) - I've tried various things to fill these in and have had some limited success with Dark Wood Scratch Cover - as it's a blend of waxes and colouring agents it flows into the scratches leaving some dark wax behind when polished. I did this about half a dozen times and its looking a lot better already.

I'm looking to build up the scratches rather than sand the Bakelite down as they are too deep. I tried running molten dark wax into the scratches but it simply wont stick and lifts off when using a razor blade. I know that on the Forum many suggest Super Glue and then sanding that down but I'd be concerned about taking the face off what is otherwise a very good Bakelite case.

Nearing the end now (collective sigh of relief !!!) having finally laid low the ghost of "The Phantom" - its been a roller coaster ride and I almost through in the towel several times! But what an education it has been and I don't think there is a single area of this set that has not been restored in some way!
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