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Old 31st Aug 2019, 3:52 pm   #1
DonaldStott
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Join Date: Aug 2015
Location: Glasgow, UK.
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Default Kolster-Brandes MR10

Picked up this K-B MR10 very cheaply at an auction over a year ago but only now finding the time to look at restoration, or should that be refurbishment?

Had a bit of a peek inside the set and it seems almost untouched although it appears that someone has wired up an external aerial of sorts - I'm hoping that this is an add-on and not something K-B rigged up themselves.

I am using "Trader" Service Sheet 1233 for the MR10 and will undertake all the usual checks before trying it with my lamp limiter.

Some initial pictures – note that I have all the original knobs: -

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Thanks to Mr Google I came across the article "It Came From Outer Sidcup" by John Ounsted in the BVWS Bulletin volume 24 number 3 Autumn 1999: -

https://www.bvws.org.uk/publications...letin_24_3.pdf

This makes slightly depressing if not alarming reading and I initially thought that the K-B MR10 might be beyond my capabilities - but wasn't sure until I got the chassis out the cabinet and did some basic checks!

Of course I had to order up some imperial hex sockets as I didn't have the required size to extract the two 4BA bolts securing the chassis mounting brackets to the cabinet! Removing the left hand bolt was a bit of a fiddle as you need to rotate the drive drum until a suitable hole aligns itself with the bolt head

I've also benefited from some early advice and guidance form Forum members David G4EBT (David Taylor) and crackle (Mike Edwards) – I had some extremely embarrassing beginners gaffs which we'll just pass over quickly but now I think I'm back on track!

The next picture shows a general view of the upper chassis and valve layout and the one after that gives some indication of the usual muck that had to be cleared out. The main variation from what is shown in the Service Sheet is the replacement of the 7-pin 6BE6 with a 9-pin Mullard ECF82 but I'll put that to one side for the moment. This set also has the MR1 Westinghouse contact-cooled metal rectifier bolted to the underside of the chassis.

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To be continued as only five images per Post are allowed.
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