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Success Stories If you have successfully repaired or restored a piece of equipment, why not write up what you did and post details here. Particularly if it was interesting, unusual or challenging. PLEASE DO NOT POST REQUESTS FOR HELP HERE! |
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28th Apr 2020, 6:40 pm | #1 |
Hexode
Join Date: Feb 2008
Location: Wrexham, North Wales, UK.
Posts: 465
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Defiant MSH546
This has been sitting in the loft for a long time, waiting to be brought back to life, so the lockdown has given me a good opportunity.
The first job was to get the knobs off - in the end I had to drill out the grub screws. At one point the drill bit broke and gashed my left thumb. The case was very knocked about with deep scratches and bits of missing veneer. I am not yet sure whether to re-veneer the front entirely or to leave it as it is - any opinions on that? I've used French polish on it as it does bring out the grain of the wood, but I may try Danish oil. There's still one knob missing, the one that's on there was the nearest I had to the right pattern. The dial was in a poor state, with flaking paint and the red markings for Long Wave almost faded away. It seemed much the simplest thing to make a new one. Electrically it was in better shape than I had expected. I changed the waxies, obviously, though the smoothing caps were all OK so I left them. It functioned reasonably well on LW and MW but was dead on SW - not a peep. A quick prod with a 'scope showed the oscillator not running. I gave the w/c switch a good cleaning, still no joy. Tracking the SW oscillator coil backwards from the switch (there's no service data for this model) I found a mica cap with one lead broken. There was just enough lead left to solder a length of wire onto. All well! A little attention to alignment improved reception throughout. The IF is 450kc/s, by the way. I am pretty sure the chassis was made by Plessey, as was the speaker. It's a solidly built, well designed set with lots of nice little touches - an IF rejector on the aerial input, for example, and some negative feedback from the O/P transformer to V4 cathode. The valves are all Mazda, by the way, and all were in good order, mostly around 90% emission. There's good sensitivity and selectivity on all bands, and SW is particularly good. With all the computers etc. in the house turned off, and the mains well filtered, the sound quality is really exceptional. I'm really chuffed with this one! |
29th Apr 2020, 6:52 pm | #2 |
Dekatron
Join Date: Jun 2009
Location: Staffordshire Moorlands, UK.
Posts: 5,271
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Re: Defiant MSH546
looks good to me! Nice dial.
My own opinion on wood restoration is to leave it if it's presentable, but go to town on it if it's already well-gone. An example might be if it's riddled with worm: sometimes you need to say, enough is enough, but yours looks to me like it's responded to what you've done quite nicely. I have 'let in' a small piece of veneer where a chunk has gone missing in the past, rather than show the bare plywood, but I aren't clever enough to colour match it and have only done it where the original finish has been stripped bare. I rather like defiants, they have a charm of their own!
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Kevin |
30th Apr 2020, 11:22 pm | #3 |
Banned
Join Date: Feb 2019
Location: Congleton, Cheshire, UK.
Posts: 609
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Re: Defiant MSH546
That has come up really nicely, great job. I too would be inclined to let the veneer be, for now at least, it doesn't stick out at all at least from that photo & it's all part of the set's life that it maybe took a knock once.
The tuning scale looks especially nice. How did you implement it, sticker or transfer onto the cleaned original plate? Also, you're not alone in your thumb becoming a casualty of lockdown. I slipped while stripping some wire for my SAC35 with a knife and wear the "prize" for my stupidity on my right thumb currently. Heal fast, and keep up the great work. |
1st May 2020, 8:27 am | #4 |
Hexode
Join Date: Jan 2018
Location: Portsmouth, Hampshire, UK.
Posts: 428
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Re: Defiant MSH546
That has come up really well! If (like me) your wood working skills are limited then, as others have said, it certainly looks the part. After having restored a Defiant MSH902 I can confirm there is little or no information out there for them. They are usually very well built as the chassis, I am led to believe, were made by Plessey. A very nice job sir, well done for getting another set working.
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