UK Vintage Radio Repair and Restoration Discussion Forum - Bush VHF70 back from the dead........

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Bush VHF70 back from the dead........

A very good (and hot!) afternoon to one & all.
I acquired this set via a well known auction site for about £20 inc postage. I just liked the look of it, the chap selling it admitted he had had it running but then there was a loud bang & it all went quiet! Not an auspicious start.
The bakelite case was dull but with a little polishing paste No. 5 it came up well. The paint work on the raised parts of the facia had seen better days with numerous chips/scratches & dinks. Some cellulose paint thinner got that off in short order. Hours spent masking it up, respraying & then finding the paint had 'bled' under the edge of the tape! A soft cloth, patience & a tiny amount of thinners got a nice line around the whole thing. The dial glass (once cleaned & polished) looks like new. The knobs, however, were a different story. Many years of twiddling & probably with wet paint on their fingers at some point had left them very grubby. I hit on an idea, common or garden liquid soap removes most contaminants from hands so why not plastic? I put the knobs in a tooth glass with 4 squirts of soap then topped up with water. Left them soaking overnight then, with an old toothbrush, they came up like new?! Who knew! A little metal polish to the metal rings & they were done. The clear plastic skirts around the knobs were originally glued but the soap had softened it sufficiently to allow the old glue to be easily removed & fresh glue to be applied. The chassis & inside of the case were covered in a thick layer of very fine dust & the secretions of wax capacitors, it makes a special kind of gunk. After checking all the valve filaments & finding them intact I then explored a little further. The original smoothing cap (dated 1959) showed no signs of distress/leakage, a quick check on the capacitance meter confirmed it was worth reforming. Most of the rubber covered wire had crumbled & was replaced. Both scale bulbs blown & a 30R WW in the return circuit had been blown to bits, this was caused by a 0.05uF cap across the mains that had gone short circuit, . ALL the waxy capacitors were way out as were the handful of Hunts moulded caps, most of those were split open. A few resistors (mostly the higher values over 100K) were as much as 50% out. The wavechange switch looked in pretty good condition so a pre-emptive squirt of Servisol switch cleaner was all it needed. Next was the tuning mechanism, more precisely the dried out grease. I've found that 3-in-1 will soften it sufficiently to remove easily. I then re-applied very sparingly a silicone based grease. This got everything moving much more easily. There was no signs that the phantom twiddler had been at large which is a good thing! Next was to apply power via a lamp limiter, nothing, not a sausage. Ammeter in line with set, no current drawn, hmmmm. You've probably already guessed that the mains switch had taken the brunt of the damage. Once taken apart & seeing the contacts were a bit worse for wear there ensued a fair bit of fettling! Successful fettling I might add. Back on the lamp limiter & for what seemed like an age nothing much happened. Then the scale lights began to glow, filaments coming up, finally a feint hint of life. No smoke, always good! On full mains all the wave bands work well on the internal aerials, I could even get Radio 4 on LW, none of my other radios can tune that in as well as this one. FM performance is good, audio clear with plenty of bass. It's on the bench now tuned to Angel Radio & sounding good. As a project it was one of the more straightforward ones but very pleasing nonetheless.